This application claims priority pursuant to 35 U.S.C. 119 (a) to Chinese Application No. 202410041282.3, filed Jan. 10, 2024, which application is incorporated herein by reference in its entirety.
Various embodiments of the present disclosure relate to current sensors, and more particularly to varying operation of current sensors to control heat generation and power consumption.
Current sensors are employed in a variety of industrial and automotive applications. For example, the monitoring of current is essential in terms of safety, performance, and efficiency of electric vehicles. However, current sensors are prone to overheating and high power consumption when used in high current or high voltage applications, such as in electrical vehicles. Applicant has identified many technical challenges and difficulties associated with conventional current sensors.
Various embodiments described herein relate to components, apparatuses, and systems for controlling a current sensor.
In accordance with various embodiments of the present disclosure, a current sensor is provided. In some embodiments, the current sensor comprises a magnetic core comprising (i) a core body and (ii) an air gap along the core body; a magnetic transducer configured in the air gap; an amplifier coupled to the magnetic transducer; a secondary winding comprising a wire coil that is extended around the core body; and a switch coupled between the amplifier and the secondary winding, the switch configured to open or close a circuit path between the amplifier and the secondary winding by operating in a continuous mode or a pulse mode based on a control signal.
In some embodiments, the amplifier is configured to receive an output voltage from the magnetic transducer; and generate an amplified voltage comprising a feedback current. In some embodiments, the switch is configured to allow the feedback current from the amplifier to the secondary winding via the circuit path. In some embodiments, the continuous mode is associated with greater measurement accuracy. In some embodiments, the pulse mode is associated with lower power consumption or a lower operating temperature. In some embodiments, the control signal comprises one or more of a close value or an open value. In some embodiments, the continuous mode comprises operating the switch based on the control signal comprising a continuous mode control signal that comprises a steady close value. In some embodiments, the pulse mode comprises operating the switch based on the control signal comprising a pulse mode control signal that comprises a plurality of alternating open values and close values.
According to another embodiment, an apparatus is provided. In some embodiments, the apparatus comprises a magnetic core comprising (i) a core body and (ii) an air gap along the core body; a Hall-effect sensor configured in the air gap; an amplifier coupled to the Hall-effect sensor; a driver coupled to the amplifier; a secondary winding comprising (i) a wire coil that is extended around the core body and (ii) a first end coupled to the driver, and (iii) a second end coupled to a sampling resistor; a switch configured to allow a feedback current from the driver to the secondary winding; and a controller unit coupled to the switch, the controller unit configured to (i) receive a digital signal based on a sampling voltage associated with the sampling resistor, (ii) generate one or more control signals based on operating condition data that comprises at least the digital signal exceeding one or more thresholds, and (iii) transmit the one or more control signals to the switch.
In some embodiments, the apparatus further comprises a temperature sensor coupled to the controller unit, the temperature sensor configured to: generate data signals representative of a temperature of the sampling resistor; and transmit the data signals to the controller unit. In some embodiments, the operating condition data comprises the data signals. In some embodiments, the switch is configured between the controller unit and the amplifier. In some embodiments, the switch is configured between the controller unit and the driver. In some embodiments, the switch is configured between the driver and the secondary winding.
According to another embodiment, a method for controlling a current sensor is provided. In some embodiments, the method comprises receiving, by one or more processors, operating condition data associated with the current sensor; determining, by the one or more processors, one or more thresholds have been exceeded based on the operating condition data; determining, by the one or more processors, a mode of operation based on the one or more thresholds; determining, by the one or more processors, a control signal type based on the mode of operation; and generating a control signal based on the control signal type, wherein (i) the control signal comprises one of a continuous mode control signal or a pulse mode control signal and (ii) is received by a switch associated with the current sensor and used to configure the current sensor to operate in the mode of operation.
In some embodiments, the operating condition data comprises temperature data, a current measurement value, or a current frequency value. In some embodiments, the one or more thresholds comprise a primary current threshold, a temperature threshold, or a primary current frequency threshold. In some embodiments, the method further comprises determining a pulse mode as the mode of operation based on a detection of a primary current that is higher than the primary current threshold or a temperature that is higher than the temperature threshold. In some embodiments, the method further comprises determining a continuous mode as the mode of operation based on a prioritization of a primary current frequency threshold over one or more of a primary current threshold or a temperature threshold. In some embodiments, the one or more thresholds comprise a safety threshold that comprises precedence over the primary current threshold, the temperature threshold, or the primary current frequency threshold. In some embodiments, the pulse mode control signal comprises one or more of phase or duty cycles that are adjustable.
The foregoing illustrative summary, as well as other exemplary objectives and/or advantages of the disclosure, and the manner in which the same are accomplished, are further explained in the following detailed description and its accompanying drawings.
The description of the illustrative embodiments may be read in conjunction with the accompanying figures. It will be appreciated that, for simplicity and clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale, unless described otherwise. For example, the dimensions of some of the elements may be exaggerated relative to other elements, unless described otherwise. Embodiments incorporating teachings of the present disclosure are shown and described with respect to the figures presented herein, in which:
Some embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the disclosure are shown. Indeed, these disclosures may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like numbers refer to like elements throughout.
As used herein, terms such as “front,” “rear,” “top,” etc., are used for explanatory purposes in the examples provided below to describe the relative position of certain components or portions of components. Furthermore, as would be evident to one of ordinary skill in the art in light of the present disclosure, the terms “substantially” and “approximately” indicate that the referenced element or associated description is accurate to within applicable engineering tolerances.
As used herein, the term “comprising” means including but not limited to and should be interpreted in the manner it is typically used in the patent context. Use of broader terms such as comprises, includes, and having should be understood to provide support for narrower terms such as consisting of, consisting essentially of, and comprised substantially of.
The phrases “in one embodiment,” “according to one embodiment,” and the like generally mean that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure, and may be included in more than one embodiment of the present disclosure (importantly, such phrases do not necessarily refer to the same embodiment).
The word “example” or “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any implementation described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other implementations.
If the specification states a component or feature “may,” “can,” “could,” “should,” “would,” “preferably,” “possibly,” “typically,” “optionally,” “for example,” “often,” or “might” (or other such language) be included or have a characteristic, that a specific component or feature is not required to be included or to have the characteristic. Such a component or feature may be optionally included in some embodiments, or it may be excluded.
A closed-loop current sensor may comprise a current measurement technique that provides galvanic and electrical isolation (e.g., without electrical contact) between a primary circuit (e.g., a measured circuit) and a sensor output for measuring the primary current of the primary circuit.
The voltage output generated by magnetic transducer 106 may be amplified by the amplifier 110 and converted to a feedback current 116. The secondary winding 108 is coupled to the amplifier 110 at a first end of the secondary winding 108 and receives the feedback current 116 such that the secondary winding 108 may generate a magnetic field that opposes the magnetic field associated with the primary current 112 thereby generating a secondary current 114 at a second end of the secondary winding 108 such that the following condition is created:
where IP may represent the primary current 112, Is may represent the secondary current 114, NP may represent a number of a primary winding associated with the conductor 102, and NS may represent a number of the secondary winding 108. As such, primary current 112 may be determined based on a derivation of secondary current 114. A sampling resistor 118 comprising a known resistance value is coupled to the second end of the secondary winding 108. The secondary current 114 may be determined by receiving a sampling voltage 120 across the sampling resistor 118 and using Ohm's law (e.g., V=IR). Primary current 112 may be determined based on the secondary current 114 using Equation 1.
Heat may be generated at sampling resistor 118 as a by-product of receiving the secondary current 114. The amount of heat generated at sampling resistor 118 may be proportional to the square of the current amperage and the resistance value according to Joule's law. As such, the larger the primary current 112, the larger the secondary current 114 and associated heat output at sampling resistor 118 may be. A larger secondary current 114 may thereby require larger power consumption by amplifier 110 to generate feedback current 116. Overheating and high power consumption are generally parameters that are monitored and desirable to minimize in applications, such as in electrical vehicles.
Various example embodiments of the present disclosure overcome such technical challenges and difficulties in current sensors and provide various technical advancements and improvements. In accordance with various examples of the present disclosure, components of example current sensors for improving current sensor performance are disclosed. In some embodiments, a closed-loop current sensor comprises a switch that is configured to either open or close a circuit of the closed-loop current sensor based on heat and power consumption conditions and requirements. In some embodiments, the switch is configured to operate in either a continuous mode or a pulse mode by, for example, a controller unit based on one or more thresholds and/or one or more optimization targets. In some embodiments, the one or more thresholds comprise a primary current threshold, a temperature threshold, and a primary current frequency threshold. In some embodiments, the one or more optimization targets comprise optimal power consumption regulation, optimal heating regulation, or overall regulation.
The magnetic transducer 206 is coupled to an amplifier 210 (e.g., an operational amplifier). A voltage output (e.g., Hall voltage) may be generated by the magnetic transducer 206 based on a magnetic flux detected by the magnetic transducer. The amplifier 210 may receive the voltage output from the magnetic transducer 216 and generate an amplified voltage signal comprising a feedback current 216. The feedback current 216 may be received at a first end of a secondary winding and driven through the secondary winding 208. The secondary winding 208 may comprise a wire coil that is extended around the core body of the magnetic core 204. In some embodiments, the secondary winding 208 comprises a helical coil of wire wound about an exterior of magnetic core 204. For example, the secondary winding 208 may comprise an Ns number of turns around the magnetic core 204. The secondary winding 208 may comprise a copper wire or any conductor suitable for conducting an electrical current.
The feedback current 216 received by the secondary winding 208 may generate an opposing magnetic field that cancels the magnetic flux created by the primary current 212, thereby resulting in a secondary current 214, at a second end of the secondary winding 208, that is proportional to the primary current 212. A sampling resistor 218 (e.g., a shunt resistor) is coupled to the second end of the secondary winding 208. The secondary current 214 may be determined by receiving a sampling voltage 220 across the sampling resistor 218 and converting the sampling voltage 220 into a digital signal usable to determine a value of the secondary current 214 based on a known resistance value of sampling resistor 218. The secondary current 214 may be used to derive and determine the primary current 212.
Current sensor 200 further comprises a switch 222 configured between the amplifier 210 and the secondary winding 208. The switch 222 may be configured to open or close a circuit path (e.g., between the amplifier 210 to the secondary winding 208) that allows a feedback current 216 to be transmitted from the amplifier 210 to the secondary winding 208, and thereby toggling operation of the current sensor 200 (e.g., on or off). According to various embodiments of the present disclosure, switch 222 is configured to operate in either a continuous mode or a pulse mode based on a control signal received from, for example, a controller unit. In some embodiments, current sensor 200 is configured to operate in a continuous mode when greater measurement accuracy (e.g., of an alternating current (AC) associated with sampling voltage 220) is desired. In some other embodiments, current sensor 200 is configured to operate in a pulse mode when lower power consumption or a lower operating temperature is desired. Examples of continuous mode control signals and pulse mode control signals that may be transmitted to and received by switch 222 are depicted in
As further depicted in
A sampling resistor 422 is configured in series with a second end of the secondary winding 412. Voltage signals may be taken from across (e.g., in parallel) the sampling resistor 422 and amplified by amplifier 414. Amplified voltage from amplifier 414 may be converted by an analog-to-digital converter 416 into a digital voltage signal suitable for input to a controller unit 418. The controller unit 418 may comprise one or more complex programmable logic devices (CPLDs), microprocessors, multi-core processors, coprocessing entities, application-specific instruction-set processors (ASIPs), microcontrollers, and/or controllers.
Further, the controller unit 418 may be embodied as one or more other processing devices or circuitry. The term circuitry may refer to an entirely hardware embodiment or a combination of hardware and computer program products. Thus, the controller unit 418 may be embodied as integrated circuits, application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), hardware accelerators, other circuitry, and/or the like.
As will therefore be understood, the controller unit 418 may be configured for a particular use or configured to execute instructions stored in volatile or non-volatile media or otherwise accessible to the controller unit 418. As such, whether configured by hardware or computer program products, or by a combination thereof, the controller unit 418 may be capable of performing steps or operations according to embodiments of the present disclosure when configured accordingly.
According to various embodiments of the present disclosure, the digital voltage signal comprises a (sampling) voltage taken across the sampling resistor 422. Given a known value of sampling resistor 422, the controller unit 418 may receive the digital voltage signal from analog-to-digital converter 416 and determine a secondary current to determine a value of the primary current 410. Thus, controller unit 418 may be configured to determine the primary current 410 based on the voltage taken across the sampling resistor 422.
A supply voltage switch 420A is coupled between the amplifier 406 and the controller unit 418. In some embodiments, the controller unit 418 may configure an operation mode of current sensor apparatus 400A by transmitting control signals to supply voltage switch 420A. Supply voltage switch 420A is coupled to a supply voltage of amplifier 406 and may be controlled by the controller unit 418 (e.g., via continuous mode and pulse mode control signals) to switch the amplifier 406 on and off.
In some embodiments, the controller unit 418 may determine an operation mode to configure any of current sensor apparatus 400A, 400B, and 400C based on component temperature, such as of sampling resistor 422. As further depicted in
According to various embodiment of the present disclosure, one or more of current sensor apparatuses 400A, 400B, or 400C operate in either continuous mode or pulse mode based on one or more operational thresholds. In some embodiments, if a primary current determined by one or more of current sensor apparatuses 400A, 400B, or 400C (based on a determination of and derivation from secondary current) is higher than a defined threshold, one or more of the current sensor apparatuses 400A, 400B, or 400C are configured by a processing device, such as controller unit 418, to operate in a pulse mode to lower power consumption. In some other embodiments, if an operating temperature (e.g., determined using temperature sensor 424) is higher than a temperature threshold, the one or more of current sensor apparatuses 400A, 400B, or 400C are configured by a processing device to operate in a pulse mode to lower heating. In some additional embodiments, if a frequency of a primary current comprising an AC current is determined by one or more of current sensor apparatuses 400A, 400B, or 400C to be higher than a threshold, the one or more of current sensor apparatuses 400A, 400B, or 400C are configured by a processing device to operate in a continuous mode thereby providing a sufficient sampling rate to ensure accurate determination of the primary current.
Referring now to
In
In some embodiments, subsequent to step 502, the example method proceeds to step 504, where the operating condition data is analyzed to determine or detect whether one or more thresholds have been exceeded. In some example embodiments, the one or more thresholds may comprise a primary current threshold TH_IP, a temperature threshold TH_temp, or a primary current frequency threshold TH_freq.
In some embodiments, subsequent to step 504, if no thresholds have been exceeded, operation condition data may continue to be received and monitored for exceeding one or more thresholds via steps 502 and 504.
In some embodiments, subsequent to step 504, if one or more thresholds have been exceeded, the example method proceeds to step 506, where a mode of operation is determined based on the one or more exceeded thresholds. For example, if a primary current determined by the current sensor is higher than a primary current threshold (e.g., 600A), the current sensor may be configured to enter a pulse mode to lower power consumption. In another example, if a current sensor's temperature (or its components) is higher than a temperature threshold (e.g., 158 F or 70° C.), then the current sensor may be configured to enter a pulse mode to lower heating. In yet another example, if a primary current frequency (e.g., frequency of the primary current comprising an AC current) is higher than a frequency threshold (e.g., 400 Hz), then the current sensor may be configured to enter a continuous mode to be able to capture the primary current operating at the primary current frequency to provide sensing accuracy.
In some embodiments, determining the mode of operation further comprises determining an optimization target. An optimization target may be determined for instances where more than one threshold are exceeded. In some embodiments, the one or more exceeded thresholds may be prioritized in dictating which mode of operation the current sensor should operate in. For example, a current sensor may be configured in pulse mode for lowering power consumption and current sensor temperature, however, measurement accuracy may be prioritized over power consumption and/or current sensor temperature. That is, a current sensor may be configured in continuous mode based on the primary current frequency exceeding a frequency threshold despite exceeding power consumption and/or current sensor temperature thresholds.
In some other embodiments, the one or more thresholds further comprise one or more safety thresholds. A safety threshold may comprise a threshold that takes precedence over non-safety threshold. For example, the primary current threshold TH_IP, the temperature threshold TH_temp, or the primary current frequency threshold TH_freq may comprise non-safety thresholds. In some example embodiments, a safety threshold comprises a safety temperature threshold or an overcurrent threshold that takes precedence over the primary current frequency threshold TH_freq. As such, in the event of exceeding a safety temperature threshold or an overcurrent threshold, a current sensor may be configured in a pulse mode or a mode where a switch status of the current sensor is configured in an open position.
As depicted in
As depicted in
As depicted in
Returning to
In some embodiments, subsequent to step 508, if the determined control signal type is a continuous mode control signal, the example method proceeds to step 510, where a continuous mode control signal is generated. In some embodiments, a continuous mode control signal comprises a steady “close” value over a given time period. The generated continuous mode control signal may be received by a switch and used to control operation of the current sensor to continuously operate and persistently obtain readings for determining primary current. In some embodiments, subsequent to step 510, the example method proceeds to step 502.
In some embodiments, subsequent to step 508, if the determined control signal type is a pulse mode control signal, the example method proceeds to step 512, where a pulse mode control signal is generated. In some embodiments, a pulse mode control signal comprises alternating “close” and “open” values over a given time period. The generated pulse mode control signal may be received by a switch and used to control operation of the current sensor to operate at periodic intervals of time and obtain readings to determine primary current during the periodic intervals of time. In some embodiments, phase and/or duty cycle associated with a pulse mode control signal may be adjusted to achieve a desired optimization target (e.g., lower power consumption, lower heating, or both) and desired sensing accuracy as well. In some embodiments, subsequent to step 512, the example method proceeds to step 502.
It is to be understood that the disclosure is not to be limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation, unless described otherwise.
Number | Date | Country | Kind |
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202410041282.3 | Jan 2024 | CN | national |