The invention relates to a receiving device for receiving a magnetic field and for producing electric energy by magnetic induction, in particular for use by a vehicle. The invention also relates to a method of manufacturing such a receiving device and to an arrangement comprising the receiving device and a rectifier. In particular, the technical application lies in the field of wireless transfer of energy to vehicles, such as road automobiles, busses vans, trucks, but also load carriers, e.g. forklift trucks, and rail vehicles. The receiving device shall be adapted to produce electric power at least at rates in the kilowatt range, e.g. 20 kW.
WO 2012/010649 A2 discloses an arrangement for receiving an electromagnetic field, for producing electric energy from the electromagnetic field by induction and for providing a load with the electric energy, in particular for providing a rail vehicle (e.g. a tram) or a road vehicle with energy. For producing electric energy by induction, the receiving arrangement comprises at least one inductor which may be realized by one or more than one windings of an electrical conductor. While a load is provided with electric energy from the receiving arrangement, the resulting alternating current produced by the inductor is rectified. An output side of the rectifier is connected to the load. The receiving arrangement may have three phases for receiving the electromagnetic field and the rectifier may be connected to the three phase lines of the receiving arrangement. Each phase comprises an inductance and a capacitance, which may be realized by in each case at least one capacitor.
There is a demand for the integration of such a receiving device or a different receiving device in existing motor vehicles, such as road automobiles. The weight of the receiving device should be small, since the maximum revenue load of the vehicle should be affected as little as possible. In addition, the construction of the receiving device and the mounting of the receiving device should be stable and also easy to assemble. Existing spaces especially in the region of the bottom of the vehicle's car body should be utilized. Typically, the magnetic field (as part of an alternating electromagnetic field) is produced by a device below the vehicle's bottom. Therefore, the receiving device which is typically mounted at the bottom of the vehicle receives the magnetic field from below, i.e. from the bottom side. However, it is possible to orient the receiving device in a different direction (such as the horizontal direction) if the magnetic field generating device is located in this direction. Generally speaking, the receiving device has a receiving side and, during operation, the magnetic field enters the receiving device or the case on the receiving side.
EP 2081792 B1 discloses a cladding element having a receiving unit integrated therein. The receiving unit comprises a receiver coil for contactless transmission of electrical energy and a plurality of flow conducting elements that are allocated to the receiver coil and designed to concentrate the field strength and are made from a material having high permeability compared with air.
It is an object of the present invention to provide a receiving device, a method of manufacturing such a receiving device and/or an arrangement comprising the receiving device and a rectifier, wherein the assembly of the receiving device is facilitated, wherein the receiving device can be assembled in a stable manner and wherein components of the receiving device shall be held in predetermined positions and/or regions of the receiving device.
According to a basic idea of the present invention, a separating structure is used which separates electric lines or bundles of electric lines of the at least one coil from each other and/or from further components of the receiving device. The separating structure comprises at least one column made of a solid material, such as plastic (e.g. polymer). The column extends in the direction from the receiving side of the receiving device to the side opposite to the receiving side.
Preferably, the separating structure comprises a plurality of columns which separate—in each case—the electric lines or bundles from each other and/or from the further components. For example, the different columns are arranged in lines and rows, wherein electric lines or bundles of electric lines of the at least one coil are separated by each column of a line or row of columns. Preferably, the lines and rows extend perpendicularly to each other and/or perpendicularly to the direction from the receiving side of the receiving device to the side opposite to the receiving side. Optionally, as described later, at least one of the columns performs further functions, such as separating other components from each other and/or from the electric lines or bundles, holding components of the receiving device and/or fixing components of the receiving device.
“Separating” means that the respective components or parts cannot contact each other. The respective dimension of the column, either in longitudinal direction, in transverse direction or in height direction, defines the minimum distance between the two parts or components which are separated. However, “separating” does not necessarily mean that there is direct contact of the separating component (in particular the column) and the respective separated component. Rather, the separating component may separate the separated components in combination with another separating component. For example, holding elements, which hold in each case one electric line or one bundle of electric lines, and a separating element, which separates the holding elements, separate the electric line(s) and/or bundle(s).
“Holding” means that a movement of the respective component or part, which is held, is not only limited by the column or holding device in one direction, but also in another direction. For example, an element which fits in a groove without clearance can be held by the groove. It cannot move beyond the edges of the groove, unless it is shifted out of the groove. Similarly, two of the columns of the separating structure which are arranged at a distance to each other can hold a bundle of the electric lines, provided that the bundle completely fills the space in between the columns. Furthermore, at least one of the columns and a further component of the receiving device, such as a plate like component, which are connected or fixed to each other may commonly hold other components of the receiving device. In addition, a single column may hold another component, such as a layer of magnetic material, of electrically insulating material or of electrically conducting material, if the column fits in a cut out of the layer without clearance with respect to at least a first direction (e.g. the longitudinal direction or the transverse direction mentioned below) and the direction opposite to the first direction.
“Fixing” means that two components which are fixed to each other cannot move relative to each other, unless the fixing is released. For example, fixing to a column of the separating structure can be realized by screwing a component of the receiving device to the column.
Using the at least one column, and in particular a plurality of columns, for separating electric lines and/or further components has the advantage that movement of the separated components is at least limited. In addition, the column can be used for other purposes, for example separating further components from each other from the electric lines, supporting other components, holding other components and fixing other components. Generally speaking, a column which extends from the receiving side to the opposite side of the receiving device can be used as a multipurpose element. It is a basic finding of the invention that such a column does not deteriorate the general performance of a receiving device, since the coil or coils can be formed so as to leave space for the column or columns and since no other interior component of the receiving device must be formed as a solid part, which completely fills a cross section of the receiving device without any cut out. Positively speaking, each interior component of the receiving device can have at least one cut out for receiving a column. The same applies to components of the same type and/or material (for example magnetic material pieces) which are to be placed next to each other so as to form a common arrangement. In particular, “interior components” means components which are arranged within a case of the receiving device.
The receiving device may comprise a case which encloses at least one coil of an electric line and further components of the receiving device. In particular, the case may comprise at least one protruding portion so that interior components can be arranged at least partially within the coil cooling portion. For example, at least one capacitor, which is electrically connected to the coil or to at least one of the coils, may be arranged in a protruding portion of the case. In any case, the at least one capacitor may have a capacitance and may be electrically connected to the coil or to at least one of the coils so as to form an electric circuit having a resonance frequency according to the inductance(s) of the coil(s) and to the capacitance(s) of the capacitor(s).
Using a case facilitates the assembly of the receiving device and the mounting of the receiving device to a unit (e.g. a vehicle). Furthermore, arranging the at least one capacitor in a protruding portion of the case makes it possible to arrange the capacitor(s) in corresponding recesses of the unit's surface. This, in turn, improves stability of the mounting and reduces the size of the further space required for mounting the receiving device next to the surface of the unit. In particular, the bottom of an existing vehicle or of an existing type of vehicles typically comprises recesses in which the protruding portion of the case of the receiving device can be arranged. In many cases, road automobiles comprise a tunnel shaped recess area at the bottom of the car body. The tunnel shaped recess is elongated and extends in the direction of travel approximately along the center line of the vehicle. Therefore, it is preferred that the case of the receiving device has a correspondingly shaped protruding portion on the top side of the case or, more generally speaking, on the side opposite to the receiving side where the magnetic field enters the receiving device during operation.
Especially an elongated protruding portion, but also any other protruding portion could be used not only for housing the at least one capacitor or at least one of the capacitors, but could also be used for receiving electrical connections from the at least one coil of the receiver to external devices, such as the rectifier. In the case of the elongated protruding portion, the connection cables can extend along the longitudinal axis of the protruding portion. In particular, the connecting cables can be connected to the at least one coil in a central region of the receiving device (in contrast to a peripheral region) and can extend to the external device through the protruding portion.
Preferably, the coil or coils of the receiving device is/are combined with ferromagnetic and/or ferrimagnetic material (such as a ferrite), which is preferably arranged on the opposite side of the receiving side if viewed from the coil or coils. Since the magnetic state of the magnetic material may change, the synonym “magnetizable material” can be used as well. In particular, the magnetic material is arranged above the coil or coils, if the receiving side is the bottom side. Thus, the field lines of the magnetic field enter the receiving device on the receiving side, penetrate the area covered by the coil or coils and are re-directed and bundled within the magnetic material so as to return to the field generating device.
Preferably, the height (measured in the direction from the receiving side to the opposite side) of the magnetic material layer differs if the receiving device comprises coils for producing different phases of an alternating electric current, wherein coils of different phases overlap each other with respect to the areas that are covered by the coils. In particular, the covered area of a coil includes the whole area around which any winding of the coil circulates. The height of the magnetic layer is larger in a first region where coils of different phases overlap, and in particular where electric lines of different coils overlap each other, compared to a second region where there is no overlap of coils of different phases or electric lines of different coils.
In particular, a layer of electrically insulating material and/or of elastic material can be arranged between the coil or coils and the magnetic material. In case of electrically conducting magnetic material, this layer insulates and in case of an elastic layer, mechanic vibrations and wear of the coils and the magnetic material is prohibited.
If the height of the magnetic material differs, it is preferred that the height difference is compensated by additional material that is lighter in weight per unit volume compared to the magnetic material. Due to the height compensation it is possible to use planar elements in regions of the receiving device beyond the magnetic layer (if viewed from the coil or coils) and hollow spaces are avoided. For example, a layer of elastic material and/or a layer of electrically conducting material (which therefore shields electromagnetic radiation) and/or a layer of electrically insulating material (which might be the base plate of an electric circuit arrangement comprising the at least one capacitor and connecting electric lines for connecting the capacitor(s) and/or the coils to an external device may be placed on the region which is formed by the magnetic material and the height compensating material.
In particular, a receiving device is proposed for receiving a magnetic field and for producing electric energy by magnetic induction, in particular for use by a vehicle, wherein
Furthermore, a method is proposed of manufacturing a receiving device for receiving a magnetic field and for producing electric energy by magnetic induction, in particular for use by a vehicle, wherein
Although the column is made of a solid material, this does not necessarily mean that the column is free of cavities. However, it is preferred that the dimensions of the column are stable, i.e. the column is not elastic.
Preferably, the receiving device comprises more than one coil of an electric line for producing an electric voltage by induction. In particular, the receiving device may comprise a plurality of electric phase lines in order to produce different phases of an alternating electric current by the induction. Each phase line forms at least one coil. Preferably, all phase lines form the same number of coils.
In particular, the coil or coils comprise in each case at least one winding of the electric line (in case of at least two phases: the phase lines) and the winding or windings of the respective coil defines a central axis around which the electric line is wound. In particular, the windings of the respective coil may circulate around an area in each case, wherein the area is substantially the same for each winding of the respective coil. Furthermore, it is preferred that all coils of the receiving device have areas enclosed by the windings, which areas have substantially (with variations of only a few percent) the same size. The central axis mentioned above penetrates the area at its center. Preferably, the coil or coils of the receiving device is/are flat, i.e. the winding or windings of each coil extend(s) in a plane and the planes of any different windings of the same coil are identical or parallel to each other. In case of plural phases, sections of the electric lines of at least one of the coils may extend outside of the plane due to the fact that electric lines of different coils and/or phases overlap each other if viewed from the receiving side.
Preferably, not only the planes of different windings of the same coil, but also the planes of the windings of different coils are identical or parallel to each other so that the complete arrangement of the coils is flat, which means that the coils cover an area, which is penetrated by the magnetic field during operation and which is significantly wider and longer compared to the total height of the coil arrangement. In particular, the height may be smaller than ⅓, preferably one ⅕ and most preferred 1/10 of the width and length of the covered area. Consequently, the coil arrangement can be housed by a housing (which is the case mentioned above) that is shaped like a flat box, i.e. a box having a small height compared to its width and length.
More generally speaking, the case has a flat configuration defining a first surface on the receiving side and a second surface on the side opposite to the receiving side, wherein the first surface and the second surface are connected by surface areas of the case which are oriented in each case to another side than the receiving side and the side opposite to the receiving side and which are smaller than the first surface and the second surface.
In particular, the case comprises a first part that forms the first surface on the receiving side and comprises a second part that forms the second surface on the side opposite to the receiving side, wherein the second part comprises the protruding portion of the case.
In particular, at least one column (preferably a plurality of columns) of the separating structure also separates different regions of magnetic material, which magnetic material is arranged on the side opposite to the receiving side if viewed from the at least one coil. This facilitates mounting of the magnetic material and guarantees that the magnetic material remains in predetermined desired positions and/or regions. Preferably, the at least one column separates the different regions of magnetic material with respect to a first direction (e.g. the transverse direction) and separates different electric lines and/or bundles of electric lines with respect to a second direction (e.g. the longitudinal direction), wherein the first direction and the second direction may extend transverse to each other, in particular perpendicularly to each other. The first and second direction may extend perpendicularly to the direction from the receiving side to the opposite side of the receiving device.
At least one column of the separating structure may extend through a cut out of a material layer, which material layer is arranged on the side opposite to the receiving side if viewed from the at least one coil. This layer may be made of elastic material. Alternatively or in addition, the material of the layer may be electrically conducting or electrically insulating. In any case, the column either holds the layer or, at least, limits movement of the layer.
At least one column of the separating structure may be fixed to a base plate of the separating structure or of a case of the receiving device, the base plate being preferably arranged on the receiving side if viewed from the at least one coil. By fixing the at least one column to the base plate, the column can be fixed in a desired, stable position. This facilitates assembling of the receiving device, since the column can be used for the assembly of other components of the receiving device as separator or holding element.
At least one further component of the receiving device may be fixed to at least one column of the separating structure. In this case, the column does not only separate the component from other components, but also fixes the component in the respective position and orientation.
The separating structure may comprise and/or may be connected to a holding device which is adapted to hold electric lines or bundles of electric lines of the at least one coil in a predetermined position. For example, the holding device may comprise grooves and one of the electric lines or a bundle of the electric lines may fit in the groove without clearance.
Embodiments of the method of manufacturing the receiving device follow from the description of the embodiments of the receiving device.
In addition, the invention refers to an arrangement comprising the receiving device, according to any embodiment described, and further comprising a rectifier, wherein the rectifier is electrically connected to the at least one coil of the receiving device and is adapted to rectify an alternating current produced by the at least one coil and wherein the rectifier is housed by a housing arranged in line with the protruding portion of the case of the receiving device.
The arrangement in line with the protruding portion means that the housing of the rectifier and the protruding portion can be arranged in an elongated recess of the surface of a unit (e.g. a vehicle), in particular at the bottom of the car body of the vehicle. If the protruding portion is elongated and comprises in particular a longitudinal axis along which the protruding portion extends, the housing of the rectifier preferably also extends along the longitudinal axis. However, there is an optional gap in between the protruding portion and the housing of the rectifier. In particular, connecting cables may extend within the gap so as to electrically connect the interior of the protruding portion with the rectifier. Preferably, the housing of the rectifier also has an elongated shape and extends along the longitudinal axis of the elongated protruding portion. Furthermore, it is possible that the height of the rectifier's housing is larger than the height of the receiving device's case with the exception of the protruding portion. This means that the case has a larger height if measured at the protruding portion compared to other regions. Preferably, the surface on the receiving side of the case is planar (i.e. extends within a plane).
Examples of the invention will be described with reference to the attached drawing. The figures of the drawing show:
The receiving device 1 shown in
In the embodiment shown in
As shown in
The protruding portions 5, 6a, 6b of the cover 3 are elongated, i.e. in each case comprise a longitudinal axis along which they extend. Preferably, the protruding portions extend along the whole length of the case and preferably have the same profile along their extension in longitudinal direction.
The protruding portion 5 is located in the center of the case (if viewed in width direction) and extends along the center line of the case, i.e. in lengthwise direction of the case. The cross section of the protruding portion 5 is trapezoidal, wherein the cross section tapers to the free top end of the protruding portion 5.
According to the specific embodiment shown in
Variations of the embodiment shown in
The exploded view of
The base part 2 of the case carries a holding device 12 for holding other interior components of the receiving device, in particular electric lines that form in each case two coils of three phases. In addition, the holding device 12 comprises a plurality of columns for separating, holding and/or fixing components of the receiving device which are located above the coils. In particular, at least one intermediate layer of insulating and/or elastic material, magnetic material, a layer of electrically conducting shield material and/or a base plate for an electric circuit arrangement can be separated, held and/or fixed using one or more than one of the columns.
When the cover 3 of the case is mounted to the base plate 2 of the case, the outer rim of the cover 3 abuts on a sealing 11 which is positioned in the periphery of the holding device 12 and is supported by the rim of the base plate 2.
A coil arrangement 31 is positioned within pre-defined receiving spaces of the holding device 12. Since the different electric lines (phase lines) for producing the different phases of an alternating current form coils which overlap each other if viewed from the top (from the cover 3), the phase lines of at least two of the phases rise nearby the longitudinal sides of the coil arrangement so that they extend along the longitudinal side one upon the other, where they overlap. Details of a specific embodiment of this kind are shown in
The coil arrangement 31 is covered by a layer 51 of elastic material which is preferably also electrically insulating. The layer 51 may be formed by a single piece of material or by a plurality of pieces.
An arrangement 61 of magnetizable material, in particular ferrimagnetic material or alternatively ferromagnetic material, is placed on the intermediate layer 51. Preferably, the height (i.e. the depth) of the magnetic material differs and is larger above (i.e. behind) regions where the density (number per length) of the electric lines of the coil arrangement 31 is higher.
Preferably, compensating material 71 is placed where the height of the magnetic material 61 is smaller so that the height of the total arrangement of magnetic material 61 and compensating material 71 is constant or, at least, varies less than the height of the magnetic material 61.
In the specific embodiment shown in
A shielding layer 91 made of electrically conducting material, for example aluminum, is placed on top of the second intermediate layer 81. The shielding layer 91 has cut outs 95 so that at least some of the columns of the holding device 12 can extend through the cut outs 95. Some cut outs or regions 96 of the cut outs can be used for placing sections of electric connections between the coil arrangement 31 and the electric circuit 111 that is placed above the shielding layer 91.
The circuit arrangement 111 is placed on a sheet-like carrier 101, such as a conventional circuit board. There is a cut out 100 in the carrier 101 so that electric connections between the circuit arrangement 111 and the coil arrangement 31 can extend through the cut out 100.
In the specific embodiment shown in
A preferred embodiment of the coil arrangement 31 is shown in
To form the two coils of one phase, the respective phase line 32, 34, 36 is wound starting at one end of a first coil around the area to be covered so as to form the first coil and further extends around the area to be covered by the second coils so as to form the second coil. In the example shown in
As mentioned before, the coils of the different phases overlap each other partially in the middle region of the coil arrangement 31. The phase lines 32, 34, 36 are placed one upon the other where the coils overlap. Since transversally extending sections of the different phase lines 32, 34, 36, which sections connect the longitudinal sides, are placed on the same height level in the finished coil arrangement 31, at least the phase lines 34, 36 rise along their extension next to the longitudinal sides of the coils. The holding device 12 defines spaces for receiving these transversely extending sections of the phase lines, wherein the spaces are on the same height level.
Although the phase lines 32, 34, 36 are preferably electrically insulated at their surfaces, the coils 33, 35, 37 of the different phases are preferably placed upon each other using distance pieces 41, 42, 43. These pieces are placed in between the phase lines 32, 34, 36 where they are placed one upon the other. In particular, there are three types of distance pieces. The first type 41 is used where the phase line 34 of the second phase is placed above the phase line 32 of the first phase along the longitudinal side of the coil arrangement 31. The first type 41 of distance pieces is elongated and extends along the longitudinal side and, at the same time, along the phase lines 32, 34 so as to form a distance between the phase lines 32, 34. The first type 41 of the distance pieces has a constant cross section. It is used for the second coil 33b of the first phase.
The second type 42 of distance pieces does not have a constant cross section, but the end region shown on the right hand side of
The third type 43 of the distance pieces also has a non-constant, varying cross section. The end regions of the distance pieces 43 are higher than the other regions. Where the height is larger, the second coil 35b of the second phase supports other components of the receiving device which are placed above the coil arrangement 31. Where the height of the distance pieces 43 is smaller, the second coil 35b or the first coil 35a of the second phase supports the first or second coil 37a, 37b of the third phase.
In particular, the number of the distance pieces 41, 42, 43 depends on the number of windings per coil. Since the number of windings may differ in different embodiments of the arrangement,
The longitudinal section of the coil 33b of the first phase is fully overlapped by the coils 35a, 35b of the second phase. If the coils 35a, 35b are placed on top of the coils 33a, 33b, the transversely extending section at the side face of coil 35b is placed outside of the area which is covered by the second coil 33b of the first phase. The transversely extending section of the second phase which comprises sections of the first coil 35a and the second coil 35b is placed in the area around which the phase line 32 of the second coil 33b of the first phase extends. The transversely extending section of the first coil 35a of the second phase is placed in the area around which the phase line 32 of the first coil 33a of the first phase extends. The corresponding arrangement can be perceived from
The coils 35 of the second phase and the coils 37 of the third phase are shifted in a similar manner relative to each other as the first phase and the second phase, but the shift length in longitudinal direction is twice as large as the shift length of the first and second phase. As a result, the transversely extending section at the side face of the first coil 37a of the third phase is placed outside of the area around which the phase line 32 of the first coil 33a of the first phase extends. On the other hand, the shift length in longitudinal direction of the third phase relative to the first phase has the same amount as the shift length of the first phase and the second phase, but is oriented in the opposite direction if viewed from the first phase coil arrangement.
At least one end of the phase line 32, 34, 36 which forms the coils of the respective phase is connected to a line section or forms a line section that extends upwards from the coils. Respective upwardly extending sections 38, 39, 40 are shown in
The enlarged view of the base plate 2 and the holding device 12 shown in
The holding device 12 comprises holding portions 16, 17 for holding electric lines or bundles of electric lines. Depending on the number of the electric lines or bundles of electric lines to be held by the individual holding portion 16, 17, the holding portions are wider or narrower (with respect to the longitudinal direction). In the example shown in
The columns 13, 14, 15 are arranged in lines extending in the longitudinal direction (from left to right in
The lines of the columns 13, 14, 15 are spaced so that pieces of magnetic material and optionally compensating material can be placed in between in each case two of the columns.
In addition, at least one of the columns 13, 14, 15 can be used for fixing other components of the receiving device to the column and thereby to the holding device 12.
Therefore, the columns combine different functions, in particular separating different transversely extending sections of coil, separating different pieces of material, such as magnetic material and compensating material, and/or fixing other components to the respective column. A further possible function is separating components of the receiving device from the basis of the holding device and/or from the basis of the receiving device at the receiving side. “Separating” means that the respective components or parts cannot contact each other. The respective dimension of the column, either in longitudinal direction, in transverse direction or in height direction, defines the minimum distance between the two parts or components which are separated.
In addition, as mentioned before, the specific embodiment of the holding device 12 shown in
Preferably, the spaces for receiving the phase lines of the coil arrangement have shaped surfaces, in particular grooved surfaces, so that the phase lines are held in place and do not slip. In particular, these spaces can be provided by holding portions of the holding device.
In particular, two columns 15 of the holding device 12 are higher than the other columns 13, 14 and serve to position and/or fix the carrier 101 and the circuit arrangement 111 shown in
The intermediate layer 51 (and optionally the intermediate layer 71) shown in
In
In order to compensate for the different heights of the magnetic material, compensating material 72 is placed as shown in
Variations of the embodiment of a field shaping arrangement shown in
At least the upper part of the circuit arrangement 111 shown in
The central protruding portion 5 of the receiving device 1 is elongated and extends along a longitudinal axis which is also the longitudinal axis of the housing 121 of the rectifier 120. This arrangement can be placed in corresponding recesses formed by the bottom surface of the car body of a road vehicle. Such a road vehicle 141 is shown in
During energy transfer to the vehicle, a generating device 142 generates the magnetic field, in particular by generating an alternating electromagnetic field. The magnetic field is indicated by three curved lines. The generating device 142 is provided with electric current from corresponding equipment 145, which may include an inverter and/or an AC/AC converter.
Modifications of the arrangement shown in
Number | Date | Country | Kind |
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1306397.9 | Apr 2013 | GB | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2014/057092 | 4/8/2014 | WO | 00 |