Patent Application
20230402219
The present invention relates to inductor coils and methods of forming or manufacturing inductor coils.
State of the inductor coils use flat helical wound copper or ribbon shaped windings for high current applications. This leads to low values of direct current resistance (DCR). This has great benefits, but a significant disadvantage relating to AC losses within the flat wound element of the coil.
To achieve low a DCR, a thicker flat copper foil >2 mm is used. This however amplifies any high frequency (HF) AC losses within the coil by anywhere from 5-20 times the normal DC losses.
There is another problematic effect that is associated with coils with such high power density, and this is due to the large gap in the core of the coil that is required to achieve desirable maximum saturation currents. Larger magnetic gaps result in larger fringing fields, and any permeable material placed close to the magnetic gap will incur eddy losses. This in turn causes areas of significant temperature rises with both stranded and flat ribbon wound coils. Some existing methods try to solve this issue by using bobbin shapes to avoid temperature hot spots, but this results in a reduction in cross sectional area that would could otherwise be utilised for copper, and also reduces the thermal performance of the coil. Other methods use a distributed gap in the core to reduce the fringing field, but this adds significant cost to the manufacturing costs.
There is a need to address these issues.
It would be advantageous to have improved inductor coil.
The object of the present invention is solved with the subject matter of the independent claims, wherein further embodiments are incorporated in the dependent claims. It should be noted that the following described aspects and examples of the invention apply also to the inductor coils and to the methods of forming inductor coils.
In a first aspect, there is provided an inductor coil, comprising:
The first component is located adjacent to the second component. A core is formed from the first component and the second component. The core is located along a first portion of a central axis and a second portion of the central axis. Along a third portion of the central axis the first component is spaced from the second component to form a gap in the core. The third portion of the central axis is between the first portion of the central axis and the second portion of the central axis. A first part of the length of conductor is located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. At least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In this manner, the coil with a compressed conductor can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example, the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an example, each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis and/or located around the second portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the third portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, a spacer is located in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In a second aspect, there is provided an inductor coil, comprising:
The first component is located adjacent to the second component. A core is formed from the second component. The core is located along a first portion of a central axis. Along a second portion of the central axis the first component is spaced from the second component to form a gap in the core. The second portion of the central axis is between the first portion of the central axis and the first component. A first part of the length of conductor is located around the first portion of the central axis, and located around the second portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. At least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In, and example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, and located around the second portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an example, each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis, wherein the inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis is spaced from the central axis by at least one first distance, and wherein the inner part of the conductor of one or more turns of the conductor located around the second portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, a spacer is located in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In a third aspect, there is provided an inductor coil, comprising:
The first component is located adjacent to the second component. A core is formed from the first component and the second component. The core is located along a first portion of a central axis and a second portion of the central axis. Along a third portion of the central axis the first component is spaced from the second component to form a gap in the core. The third portion of the central axis is between the first portion of the central axis and the second portion of the central axis. A first part of the length of conductor is located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. Each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis and/or located around the second portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the third portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, a spacer is located in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, at least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis.
Inductor coil according to any of claims 31-40, wherein adjacent turns of the plurality of turns of conductor are bonded to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In a fourth aspect, there is provided an inductor coil, comprising:
The first component is located adjacent to the second component. A core is formed from the second component. The core is located along a first portion of a central axis. Along a second portion of the central axis the first component is spaced from the second component to form a gap in the core. The second portion of the central axis is between the first portion of the central axis and the first component. A first part of the length of conductor is located around the first portion of the central axis, and located around the second portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. Each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis is spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the second portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, a spacer is located in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, at least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In, and example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, and located around the second portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In a fifth aspect, there is provided a method of forming an inductor coil, comprising:
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In, and example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, around the second portion of the central axis, and around the third portion of the central axis.
In an example, the method comprises bonding adjacent turns of the plurality of turns of conductor to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an example, the method comprises locating the length of conductor such that each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis and/or located around the second portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the third portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, the method comprises locating a spacer in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In a sixth aspect, there is provided a method of forming an inductor coil, comprising:
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, and around the second portion of the central axis.
In an example, the method comprises bonding adjacent turns of the plurality of turns of conductor to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an example, the method comprises locating the length of conductor such that each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis is spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the second portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, the method comprises locating a spacer in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In a seventh aspect, there is provided a method of forming an inductor coil, comprising:
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the method comprises locating a spacer in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor in the direction of the central axis.
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, the at least one of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In, and example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, around the second portion of the central axis, and around the third portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an eighth aspect, there is provided a method of forming an inductor coil, comprising:
In other words, the turns of the conductor at the position of the gap in the core are spaced further from axis of the inductor coil than the other turns around the core. This can be through either displacement of the turns sideways, or deformation of the inner part of the conductor turns facing the axis of the inductor coil. In this manner, the inductor coil does not lead to induced eddy currents that would otherwise be caused by conductive material being present in these fringing fields. This avoids temperature hotspots, maximises the available cross-sectional area of conductor, and maximises the thermal performance of the coil.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the method comprises locating a spacer in the gap in the core to form a gap around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In other words, the spacer is positioned in the gap in the core, and is wider than the diameter of the core, and when the first part of the length of conductor is located around the core and gap in the core, the spacer forms a space around the outer extent of the gap in the core, by either in effect pushing conductor turns sideways, and/or deforming the inner part of each conductor turn at the location of the gap in the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor in the direction of the central axis.
In this manner, compressed coil can achieve lower or equal DCR than existing coils, but at the same time the AC losses rather than being 5-20 times the DC losses now only 1-3 times the DC losses.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
By compressing the conductor during assembly of the inductor coil mitigates putting tension in the wire for wire that has already been fully compressed, and that is then would around the core. The wire can however be partially compressed prior to being wound around and/or located around the core, and then further compressed as the first and second components are brought together and further compressing the conductor.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, and around the second portion of the central axis.
In an example, the method comprises bonding adjacent turns of the plurality of turns of conductor to each other.
This for example, facilitates prior compression of the first part of the length of conductor before it is located around the core gap in the core of the inductor coil, parts of the conductor turns may not then be under compression between the base portions of the first component and second component, but remain in a compressed tight arrangement.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
Advantageously, the benefits provided by any of the above aspects equally apply to all of the other aspects and vice versa.
The above aspects and examples will become apparent from and be elucidated with reference to the embodiments described hereinafter.
Exemplary embodiments will be described in the following with reference to the following drawings:
In an example an inductor coil comprises a first component 12, a second component 14, and a length of conductor 18. The first component is located adjacent to the second component. A core 16 is formed from the first component and the second component. The core is located along a first portion of a central axis and a second portion of the central axis. Along a third portion of the central axis the first component is spaced from the second component to form a gap 20, 30 in the core. The third portion of the central axis is between the first portion of the central axis and the second portion of the central axis. A first part of the length of conductor is located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. At least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
In an example, each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis and/or located around the second portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the third portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In an example, a spacer 30 is located in the gap in the core to form a gap 22 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole 32 configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In an example an inductor coil comprises a first component 12, a second component 14, and a length of conductor 18. The first component is located adjacent to the second component. A core 16 is formed from the second component. The core is located along a first portion of a central axis. Along a second portion of the central axis the first component is spaced from the second component to form a gap 40, 50 in the core. The second portion of the central axis is between the first portion of the central axis and the first component. A first part of the length of conductor is located around the first portion of the central axis, and located around the second portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. At least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, and located around the second portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
In an example, each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the second portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In an example, a spacer 50 is located in the gap in the core to form a gap 42 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In an example an inductor coil comprises a first component 12, a second component 14, and a length of conductor 18. The first component is located adjacent to the second component. A core 16 is formed from the first component and the second component. The core is located along a first portion of a central axis and a second portion of the central axis. Along a third portion of the central axis the first component is spaced from the second component to form a gap 20, 30 in the core. The third portion of the central axis is between the first portion of the central axis and the second portion of the central axis. A first part of the length of conductor is located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. Each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis and/or located around the second portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the third portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, a spacer 30 is located in the gap in the core to form a gap 22 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole 32 configured to be located around the central axis.
In an example, at least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, located around the second portion of the central axis, and located around the third portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
In an example, an inductor coil comprises a first component 12, a second component 14, and a length of conductor 18. The first component is located adjacent to the second component. A core 16 is formed from the second component. The core is located along a first portion of a central axis. Along a second portion of the central axis the first component is spaced from the second component to form a gap 40, 50 in the core. The second portion of the central axis is between the first portion of the central axis and the first component. A first part of the length of conductor is located around the first portion of the central axis, and located around the second portion of the central axis to form a plurality of turns of conductor around the core and the gap in the core. Each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis is spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the second portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, a spacer 50 is located in the gap in the core to form a gap 42 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the outer surface of the portion of the spacer is configured to contact the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, at least one section of the first part of the length of conductor is compressed in the direction of the central axis.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component is compressed between and by the base portion of the first component and the base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the first part of the length of conductor is at least partially compressed prior to being located around the first portion of the central axis, and located around the second portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In an example, a method of forming an inductor coil comprises:
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, around the second portion of the central axis, and around the third portion of the central axis.
In an example, the method comprises bonding adjacent turns of the plurality of turns of conductor to each other.
In an example, method comprises locating the length of conductor such that each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis and/or located around the second portion of the central axis is/are spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the third portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In an example, the method comprises locating a spacer 30 in the gap in the core to form a gap 22 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole 32 configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In an example, a method of forming an inductor coil comprises
It is to be noted, that the method steps can be carried out in different orders and certain steps can be carried out contemporaneously, and certain steps can be carried out more than once—for example the compressing step.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the at least one of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, and around the second portion of the central axis.
In an example, the method comprises bonding adjacent turns of the plurality of turns of conductor to each other.
In an example, the method comprises locating the length of conductor such that each turn of conductor of the plurality of turns of conductor has an inner part of the conductor spaced at least one distance from the central axis in a direction perpendicular to the central axis. The inner part of the conductor of two or more turns of the conductor located around the first portion of the central axis is spaced from the central axis by at least one first distance. The inner part of the conductor of one or more turns of the conductor located around the second portion of the central axis is spaced from the central axis by at least one second distance greater than the at least one first distance.
In an example, the method comprises locating a spacer 50 in the gap in the core to form a gap 42 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
In an example, a method of forming an inductor coil comprises:
It is to be noted, that the method steps can be carried out in different orders and certain steps can be carried out contemporaneously.
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the method comprises locating a spacer 30 in the gap in the core to form a gap 22 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the first component and an outer surface of the second component that form the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the first component and the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the third portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole 32 configured to be located around the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor in the direction of the central axis.
In an example, the at least one of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example, the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, around the second portion of the central axis, and around the third portion of the central axis.
In an example, adjacent turns of the plurality of turns of conductor are bonded to each other.
In an example, a method of forming an inductor coil comprises:
In an example, a second part and a third part of the length of conductor at the ends of the length of conductor form part of connection terminals of the inductor coil.
In an example, the whole of the first part of the length of the conductor is compressed.
In an example, the method comprises locating a spacer 50 in the gap in the core to form a gap 42 around the core. An outer surface of a portion of the spacer is located a distance from the central axis that is greater than a distance from the central axis of an outer surface of the second component that forms the core.
In an example, a dimension of the portion of the spacer adjacent to the outer surface of the second component in the direction of the central axis is greater than a dimension of the gap 24 in the core in the direction of the central axis.
In an example, the method comprises contacting the outer surface of the portion of the spacer with the one or more turns of conductor located around the second portion of the central axis.
In an example, the spacer comprises a non-conductive material.
In an example, the spacer comprises a central hole configured to be located around the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor in the direction of the central axis.
In an example, the at least one section of the first part of the length of conductor that is compressed has a dimension of the conductor in the direction of the central axis that is less than a dimension of the conductor in a direction perpendicular to the central axis.
In an example, the method comprises compressing at least one section of the first part of the length of conductor between a base portion of the first component and a base portion of the second component.
In an example, the whole of the first part of the length of conductor can be compressed prior to being located around the core and gap in the core. In an example the first and second base portions can have base portions that only extend laterally over a certain angular range. Then the first part of the length of the conductor can be located around the core and gap in the core, and then the base portions of the first and second parts are moved toward each other and then the length of the conductor over these angular ranges can then be further compressed by the base portions.
In an example the first part of the length of the conductor can be located around the core and the gap in the core, and then the base portions of the first and second parts are moved toward each other and only the conductor at the angular positions where the base portions face one another is compressed.
In an example, the method comprises at least partially compressing the first part of the length of conductor prior to locating it around the first portion of the central axis, and around the second portion of the central axis.
In an example, the method comprises bonding adjacent turns of the plurality of turns of conductor to each other.
In an example, the first component comprises a ferrite material.
In an example, the second component comprises a ferrite material.
In an example, the conductor comprises a multi-strand wire.
In an example, the conductor comprises a Litz wire.
Thus, a new technology has been developed that in specific embodiments utilizes a deformable conductor formed for example from multi-stranded wire or Litz wire/coils and methods for gap distribution of the fringing field that provides for copper packing by compressing the conductor wire, including for example after it has been formed around the core area shape, and also avoiding the fringing field to achieve a high performance coil with low thermal heat generation and brilliant thermal transfer.
Specifically:
Specific embodiments are now described, where reference is again made to
In an example the pre-shaped conductor 18, including the pre-shaped free space 22, is manufactured using a winding machine, which is controlling and shaping the cross sectional shape of the conductor 18 turn by turn in a design which results in a screw type arrangement of the windings along a central axis 10 of the coil. Such arrangements are shown in
In an example the windings of the coil are pre-shaped into a screw type arrangement around a central axis with a inner open diameter which is designed to fit into the open volume of the magnetic flux ring made from part 12 and 14. The screw type winding is then compressed at least partially in axial direction and the winding cross-section is expanded radially according to this compression. The total cross-sectional area of the windings can remain about the same through compression, thus the compression and the change of the cross-sectional shape is associated with a geometrical re-arrangement of the fibers of the thin wires or filaments of the conductor 18, which are forming the compressed part of the conductor
Thus, a new inductor coil is provided that has a gap in the core, either centrally between to ferrite components or next to one of the ferrite components, with a gap is either an air gap or has a nonconductive spacer. The gap can be important in inductor design, because it can be used with respect to the control of magnetic resistance in magnetic circuit. However, now eddy currents in the windings of the coil are prevented because the wire is kept away from this. Furthermore, copper density of the overall windings of the inductor coil increased due to deformation of the windings through compression, which can occur before and/or during the mounting process. When a nonconductive spacer is utilised, it helps to keep the conductor out of the eddy current space, acts like a pusher will to form a and keeps at least one winding in a deformed geometry, and indeed a counter twist can be provided that creates a partially more parallel (than twisted) multi-strand wire.
The following relates to examples, that provide specific details on a number of possible arrangements of the inductor coils, and specific details on a number of possible ways of forming the inductor coils
It has to be noted that embodiments of the invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims whereas other embodiments are described with reference to the device type claims. However, a person skilled in the art will gather from the above and the following description that, unless otherwise notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters is considered to be disclosed with this application. However, all features can be combined providing synergetic effects that are more than the simple summation of the features.
While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing a claimed invention, from a study of the drawings, the disclosure, and the dependent claims.
In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfill the functions of several items re-cited in the claims. The mere fact that certain measures are re-cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20204342.8 | Oct 2020 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/079753 | 10/27/2021 | WO |
