Power assembly and electronic equipment

Abstract

The utility model discloses a power assembly and electronic equipment, and belongs to the technical field of power electronics. The power assembly includes: a plurality of power devices connected in parallel; wherein the power device controls current output by the power device according to an electric signal of a control end of the power device; the plurality of non-contact current detection devices are in one-to-one correspondence with the power devices, the first output ends of the non-contact current detection devices are mutually connected, and the second output ends of the non-contact current detection devices are respectively connected with the control ends of the power devices; wherein the non-contact current detection device is used for detecting the current output by the corresponding power device, and the polarity of the second output end is configured to enable a signal of the second output end to act on the control end to form negative feedback regulation on the current output by the power device. The embodiment of the utility model can provide a current balancing scheme with high reliability.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of power electronics, especially to a power assembly and electronic equipment. BACKGROUND

[0002] At present, parallel power devices have current imbalance problem. Due to the limitation of cost and process, the upstream side solution of improving the consistency of device parameters by screening the parameters of parallel devices and improving the consistency of circuit parasitic parameters by improving the circuit geometry of parallel devices is difficult to realize. Therefore, the downstream side solution of adjusting the gate drive is often used in the related art.

[0003] However, the circuit structure for realizing the adjustment of the gate drive is usually complex, and the complex circuit structure will reduce the reliability of the parallel system. SUMMARY

[0004] The utility model provides a kind of power assembly and electronic equipment to provide a kind of current equalization scheme with high reliability.

[0005] In the first aspect, the utility model embodiment provides a kind of power assembly, comprising:

[0006] A plurality of parallelly connected power devices;Wherein, the power device is according to the electric signal of its control end to control the current output by the power device;

[0007] A plurality of non-contact current detection devices corresponding to each power device, the first output end of each non-contact current detection device is connected, and the second output end of each non-contact current detection device is connected to the control end of each power device;Wherein, the non-contact current detection device is used to detect the current output by the corresponding power device, and the polarity of the second output end is configured to: the signal of the second output end acts on the control end, to form negative feedback regulation to the current output by the power device.

[0008] Optionally, the current output by the power device is positively correlated with the electric signal of the control end, the first output end is the positive output end of the non-contact current detection device, and the second output end is the negative output end of the non-contact current detection device.

[0009] Optionally, the current output by the power device is negatively correlated with the electric signal of the control end, the first output end is the negative output end of the non-contact current detection device, and the second output end is the positive output end of the non-contact current detection device.

[0010] Optionally, the power device is a voltage-controlled power device or a flow-controlled power device.

[0011] Optionally, the non-contact current detection device is a passive device.

[0012] Optionally, the non-contact current detection device comprises a Rogowski coil or a current transformer.

[0013] Optionally, the non-contact current detection device comprises a Hall sensor.

[0014] Optionally, the non-contact current detection device is an electromagnetic induction-based current sensor; an electromagnetic induction coupling coefficient of the current sensor is positively correlated with a preset compensation strength, the preset compensation strength being a preset change amount of an electric signal provided to a control end of the power device when a unit of current change output by the power device occurs.

[0015] The electromagnetic induction coupling coefficients of the current sensors are consistent.

[0016] Optionally, the power device is a packaged power device, and a control pin of the packaged power device serves as the control end.

[0017] The power assembly further comprises a circuit board; the packaged power devices and the non-contact current detection devices are arranged on the circuit board, and the second output end of the non-contact current detection device is connected to the control pin of the packaged power device through circuit traces on the circuit board.

[0018] Alternatively,

[0019] The power device is an unpackaged bare power chip, a control pole of the bare power chip serves as the control end, and the second output end of the non-contact current detection device is connected to the control pole of the bare power chip through a bonding wire; the bare power chips and the non-contact current detection devices are collectively packaged to form the power assembly.

[0020] In a second aspect, the utility model embodiment further provides an electronic device, comprising: the power assembly provided in any of the utility model embodiments.

[0021] Optionally, the electronic device further comprises a driver connected to the control ends of the power devices respectively.

[0022] The power assembly provided by the embodiment of the utility model, for each power device connected in parallel, one non-contact current detection device is arranged to detect the current output by the power device, the first output ends of the non-contact current detection devices are connected to each other, the second output ends of the non-contact current detection devices are connected to the control ends of the power devices respectively, and the polarity of the second output ends is configured, so that a compensation network for negatively feeding back and adjusting the current output by the power device according to the detected current is formed. When there are power devices with different output currents, circulating current is naturally formed in the compensation network, so that different direction compensation electric signals are provided to the control ends of the power devices with larger and smaller currents, the output currents of the power devices tend to be consistent through the negative feedback adjustment of the currents output by the power devices, and the current imbalance is alleviated. The compensation network is only composed of a plurality of non-contact current detection devices, the original connection circuit of the parallel power devices does not need to be damaged, the circuit structure is simple and easy to implement, the cost and process difficulty are relatively low, the compensation network structure is simple, a large number of device connections are not needed, and too many connection nodes are not generated, so that the risk of failure of the compensation network itself can be effectively reduced, and the error caused by data transmission or conversion between a plurality of functional modules is reduced, so that the reliability of the current equalization of the parallel devices is effectively improved. Therefore, the utility model embodiment provides a current equalization scheme with high reliability, and the current equalization of the parallel power devices can be simply and effectively optimized.

[0023] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the utility model, and is not used to limit the scope of the utility model. Other features of the utility model will become easy to understand through the following description. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical scheme in the embodiment of the utility model, the drawings needed in the embodiment description will be simply introduced below, and obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained according to these drawings without creative labor for those skilled in the art.

[0025] Figure 1 is a structural schematic view of a power assembly provided by the embodiment of the utility model;

[0026] Figure 2 is a structural schematic view of another power assembly provided by the embodiment of the utility model;

[0027] Figure 3 is a structural schematic view of another power assembly provided by the embodiment of the utility model;

[0028] Figure 4It is a structural schematic diagram of an electronic device provided by the embodiment of the utility model. DETAILED DESCRIPTION

[0029] In order to make the person in the art better understand the utility model scheme, the technical scheme in the embodiment of the utility model will be clearly and completely described below in combination with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, rather than all the embodiments. Based on the embodiment in the utility model, all other embodiments obtained by the person skilled in the art without making creative labor should belong to the protection scope of the utility model.

[0030] It should be noted that the terms "first", "second" and the like in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the utility model described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion.

[0031] As mentioned in the background, the gate drive regulation circuit structure under the parallel application of multi-power devices is complex, and the specific analysis is as follows: when the device package and the circuit structure are basically fixed, the solution of the downstream meter usually adopts an active gate drive method. Specifically, the current measurement probe is used to measure the current of each power device in parallel, the signal conditioning and signal conversion circuit is used to convert the analog quantity detected by the probe into digital data, the controller is used to process the current difference and generate a control quantity, and then the control quantity is converted into a current by the front-end implementation circuit and injected into the device gate to realize the equalization of the current of each device according to the theoretical basis that the gate voltage determines the device current. In addition, the power supply circuit and the communication circuit required by the active gate drive also need to be provided. The complex gate drive regulation circuit will increase the application cost on the one hand, and the complex circuit is prone to failure, which affects the reliability of the device.

[0032] To solve the above technical problems, the utility model provides a kind of power assembly, realizes a current equalization scheme with high reliability. The circuit is specifically described below.

[0033] Figure 1 It is a structural schematic diagram of a power assembly provided by the embodiment of the utility model, referring to Figure 1The power assembly comprises: a plurality of power devices connected in parallel; and a plurality of non-contact current detection devices corresponding to the power devices respectively. The power devices control the current output by the power devices according to the electrical signal of the control end of the power devices. The first output ends of the non-contact current detection devices are connected to each other, and the second output ends of the non-contact current detection devices are connected to the control ends of the power devices respectively. The non-contact current detection devices are configured to detect the current output by the corresponding power devices. The polarity of the second output end of the non-contact current detection device is configured such that the signal of the second output end acts on the control end, thereby forming a negative feedback regulation on the current output by the power device.

[0034] Figure 1 Three power devices are exemplified in the figure, which are a first power device 11, a second power device 12 and a third power device 13. Correspondingly, three non-contact current detection devices are provided, which are a first current detection device 21, a second current detection device 22 and a third current detection device 23. The non-contact current detection devices are configured to detect the current on the line connected to the corresponding power device, as the current output by the corresponding power device. Specifically, refer to the figure. Figure 1 The first current detection device 21 can be sleeved on the line connected to the first power device 11 to detect the current i1 output by the first power device 21. The second current detection device 22 can be sleeved on the line connected to the second power device 12 to detect the current i2 output by the second power device 22. The third current detection device 23 can be sleeved on the line connected to the third power device 13 to detect the current i3 output by the third power device 23. The first output ends of the three non-contact current detection devices are connected to each other. The second output end of the first current detection device 21 is connected to the control end G1 of the first power device 11, the second output end of the second current detection device 22 is connected to the control end G2 of the second power device 12, and the second output end of the third current detection device 23 is connected to the control end G3 of the third power device 13. It can be understood that the number of the power devices and the non-contact current detection devices is not limited to the present application. In actual application, the number of the power devices can be set according to actual needs, and the same number of non-contact current detection devices can be set to form a compensation network.

[0035] The power device can also be referred to as a power electronic device, including electronic devices for power conversion and control, such as including transistors. Taking a MOSFET (Metal-Oxide Semiconductor Field Effect Transistor) as an example, the gate is used as the control terminal. The MOSFET can control the current flowing between the source and the drain according to the voltage of the gate, so as to control the output current according to the electrical signal of the control terminal. It can be understood that the power device is not limited to MOSFET, but can also be GTR (Giant Transistor), GTO (Gate Turn-Off Thyristor) and IGBT (Insulate-Gate Bipolar Transistor), etc. The specific selection can be made according to the actual needs. For example, the same plurality of power devices are connected in parallel in the same power assembly. Taking the power device as a MOSFET as an example, the plurality of MOSFETs can be connected in parallel by connecting the sources of the MOSFETs to each other and connecting the drains of the MOSFETs to each other. The same applies to other types of power devices, and will not be repeated here.

[0036] The non-contact current detection device, also known as an isolated current detection device, can achieve current sensing through a non-contact current method, which can avoid direct interaction with the current-carrying line and reduce the risk of damage to the parallel power device structure. Specifically, the non-contact current detection device can sense the current on the line where the power device is located based on the principle of electromagnetic induction, and the detected current size can be represented by the electrical signal between the two output terminals of the non-contact current detection device. For example, the electrical signal between the first output terminal and the second output terminal of the non-contact current detection device is positively correlated with the current output by the power device. The non-contact current detection device can be arranged corresponding to the line where the corresponding power device is located through a sleeve connection or a mounting manner, and the specific arrangement manner is not limited here.

[0037] In the embodiment, the first output terminals of the non-contact current detection devices are connected together, and the second output terminals of the non-contact current detection devices are connected to the control terminals of the power devices one by one, a compensation network is formed based on the non-contact current detection devices, when the currents output by the parallelly connected power devices are different, a circulating current is formed in the compensation network, and the electrical signals at the control terminals of the power devices tend to be consistent through the compensation network. Specifically, the polarity of the second output terminal is configured such that the signal at the second output terminal acts on the control terminal, thereby forming a negative feedback regulation on the current output by the power device. When there is a power device with inconsistent output current, the electrical signals output by the non-contact current detection devices are different. Since the first output terminals of the non-contact current detection devices are connected together and have the same potential, the second output terminals of the corresponding non-contact current detection devices can naturally provide different electrical signal compensation directions for the power device with larger current and the power device with smaller current, thereby achieving negative feedback compensation on the current output by the power device. Specifically, the current output by the power device with larger current is reduced, and the current output by the power device with smaller current is increased, so that the currents output by the power devices tend to be consistent, thereby improving the current imbalance problem between the parallelly connected devices. For example, the non-contact current detection devices are the same current detection devices, and are arranged at the same position of the circuit line of the power device in the same manner, so as to avoid the influence of detection error on the current sharing effect.

[0038] The power assembly provided by the embodiment of the utility model, for each power device connected in parallel, one non-contact current detection device is arranged to detect the current output by the power device, the first output ends of the non-contact current detection devices are connected to each other, the second output ends of the non-contact current detection devices are connected to the control ends of the power devices respectively, and the polarity of the second output ends is configured to form a compensation network for negative feedback regulation of the current output by the power device according to the detected current. When there are power devices with different output currents, circulating current is naturally formed in the compensation network, thereby providing compensation electric signals in different directions to the control ends of the power devices with larger and smaller currents, and the output currents of the power devices tend to be consistent through negative feedback regulation of the currents output by the power devices, thereby relieving the current imbalance. The compensation network is only composed of multiple non-contact current detection devices, does not need to damage the original connection circuit of the power devices connected in parallel, has simple and easy circuit structure, and has lower cost and process difficulty, and the compensation network has simple structure, does not need complicated device connection, and will not generate too many connection nodes, so that the risk of failure of the compensation network itself can be effectively reduced, and the error caused by data transmission or conversion between multiple functional modules can be reduced, thereby effectively improving the reliability of current equalization of the parallel devices. Therefore, the utility model embodiment provides a current equalization scheme with high reliability, which can simply and effectively optimize the current equalization of the parallel power devices.

[0039] On the basis of the above-mentioned embodiments, optionally, the power device is a voltage-controlled power device or a current-controlled power device. For the voltage-controlled power device, the electrical signal of the control terminal is a voltage signal; for the current-controlled power device, the electrical signal of the control terminal is a current signal. However, for both the voltage-controlled power device and the current-controlled power device, the compensation network can adjust the electrical signal of the control terminal of the power device by injecting or extracting current to the control terminal of the power device. Specifically, for the voltage-controlled power device, the gate is the control terminal, and the second output terminal of the non-contact current detection device injects or extracts current to the gate of the voltage-controlled power device, which is equivalent to injecting or extracting current to the gate capacitor of the voltage-controlled power device, so as to adjust the gate voltage of the voltage-controlled power device. For the current-controlled power device, the base is the control terminal, and the second output terminal of the non-contact current detection device injects or extracts current to the base of the current-controlled power device, so as to directly adjust the base current of the current-controlled power device. Therefore, for any type of power device, the compensation network formed by the non-contact current detection devices actually forms a compensation current source by sensing the output current of the power device, and adjusts the electrical signal of the control terminal of the power device by current compensation by injecting or extracting current to the control terminal of the power device. For example, the voltage-controlled power device can be MOSFET, IGBT and the like; the current-controlled power device can be SCR (Silicon Controlled Rectifier) and GTO and the like. For example, the power device can be a silicon carbide power device. Therefore, the power assembly provided in the embodiment has a wide application range and is suitable for various types of power devices.

[0040] On the basis of the above-mentioned embodiments, the polarity of the second output terminal of the non-contact current detection device can be configured according to the type of the power device, which will be described below.

[0041] Figure 2 is a structural schematic diagram of another power assembly provided in the embodiment of the utility model, see Figure 2 In an embodiment, optionally, the current i output by the power device 10 is positively correlated with the electrical signal of the control terminal G of the power device 10, that is, the greater the electrical signal of the control terminal G of the power device 10, the greater the current i output by the power device 10. Correspondingly, the first output terminal is the positive output terminal of the non-contact current detection device 20, and the second output terminal is the negative output terminal of the non-contact current detection device 20. That is, the positive output terminals of the non-contact current detection devices 20 are connected together, and the negative output terminals of the non-contact current detection devices 20 are respectively connected to the control terminals G of the power devices 10.

[0042] Thus, the control end G of each power device 10 can be negatively fed back according to the detected current, and the output current of each power device 10 can be negatively fed back. Specifically, when the output current i of any power device 10 increases, the electric signal sensed by the corresponding non-contact current detecting device 20 also increases, and the positive output ends of all the non-contact current detecting devices 20 are connected together and have the same electric signal. Therefore, for the non-contact current detecting device 20 whose sensed output electric signal increases, the electric signal provided by the negative output end of the non-contact current detecting device 20 to the control end G of the power device 10 decreases, so that the output current of the power device 10 decreases accordingly. When the output current i of any power device 10 decreases, the electric signal sensed by the corresponding non-contact current detecting device 20 also decreases, so that the electric signal provided by the negative output end of the non-contact current detecting device 20 to the control end G of the power device 10 increases, so that the output current of the power device 10 increases accordingly. Therefore, for the power device whose output current is positively correlated with the control end signal, the negative feedback compensation of the current can be finally realized through the negative feedback compensation of the control end voltage according to the output current.

[0043] Specifically, taking the voltage-controlled power device as an example, for example, NMOS, the implementation of the current balance compensation is based on two core principles: 1. The non-contact current detecting device 20 can generate an electric signal output positively correlated with the measured current; 2. The voltage-controlled power device can control its output current by controlling the voltage of its control end G (for example, the gate). Then, for each power device 10 in parallel, the negative output end of the non-contact current detecting device 20 is connected to the control end G (for example, the gate) of the power device 10, so as to negatively feed back the voltage of the control end G, and since the voltage of the control end G is positively correlated with the output current i of the power device 10, the negative feedback of the current i can be realized. Therefore, for any power device 10, the control process of increasing the output current i of the power device 10→ increasing the electric signal sensed by the non-contact current detecting device 20→ decreasing the voltage of the control end G of the power device 10→ decreasing the output current i of the power device 10 can be naturally realized by setting the compensation network composed of the non-contact current detecting devices 20, so as to realize the current balance.

[0044] Specifically, for the voltage-controlled power device, for example, NMOS, the implementation of the current balance compensation is based on two core principles: 1. The non-contact current detecting device 20 can generate an electric signal output positively correlated with the measured current; 2. The voltage-controlled power device can control its output current by controlling the voltage of its control end G (for example, the gate). Then, for each power device 10 in parallel, the negative output end of the non-contact current detecting device 20 is connected to the control end G (for example, the gate) of the power device 10, so as to negatively feed back the voltage of the control end G, and since the voltage of the control end G is positively correlated with the output current i of the power device 10, the negative feedback of the current i can be realized. Therefore, for any power device 10, the control process of increasing the output current i of the power device 10→ increasing the electric signal sensed by the non-contact current detecting device 20→ decreasing the voltage of the control end G of the power device 10→ decreasing the output current i of the power device 10 can be naturally realized by setting the compensation network composed of the non-contact current detecting devices 20, so as to realize the current balance. Figure 2 When the output currents i of all the parallel power devices 10 are completely balanced, the electric signals output by the non-contact current detecting devices 20 are equal. According to Kirchhoff's law, the compensation network does not change the voltage of the control end G of any power device 10, that is, the compensation network does not affect the balanced parallel device circuit. The entire parallel device circuit operates normally as if the compensation network does not exist.

[0045] When there is current imbalance among the parallel power devices, the electrical signals output by the at least partial non-contact current detection devices 20 are not equal, thus causing circulating current in the compensation network. Here, taking the first to third power devices from left to right as an example, the currents output by the first to third power devices are denoted as i1, i2 and i3 in sequence. It is assumed that i1 is relatively large, while i2 and i3 are relatively small. Taking the non-contact current detection devices 20 to sense the currents and output voltages as an example, taking the first to third non-contact current detection devices from left to right, the voltages output by the first to third non-contact current detection devices are denoted as v1, v2 and v3 in sequence, then v1 will be greater than v2 and v3. At this time, the compensation network will extract current from the control end of the first power device, and inject current to the control ends of the second and third power devices, thereby weakening the voltage at the control end of the first power device, and enhancing the voltages at the control ends of the second and third power devices. Since each power device 10 is a voltage-controlled power device with output current positively correlated with the control end voltage, the final effect after compensation by the compensation network is to reduce i1 and increase i2 and i3, which exactly plays a reverse compensation role on the original current imbalance.

[0046] Figure 3 is another structural schematic diagram of a power assembly provided by the embodiment of the present application, referring to Figure 3 In another embodiment, optionally, the current i output by the power device 10 is negatively correlated with the electrical signal of the control end G of the power device 10, that is, the greater the electrical signal of the control end G of the power device 10, the smaller the current i output by the power device 10. Correspondingly, the first output end is the negative output end of the non-contact current detection device 20, and the second output end is the positive output end of the non-contact current detection device 20, that is, the negative output ends of the non-contact current detection devices 20 are connected together, and the positive output ends of the non-contact current detection devices 20 are respectively connected to the control ends G of the power devices 10.

[0047] In this way, positive feedback of the control end G electrical signal of each power device 10 can be realized according to the detected current, and then negative feedback of the current output by each power device 10 can be realized. Specifically, when the current i output by any power device 10 increases, the electrical signal sensed by the corresponding non-contact current detection device 20 also increases, and the negative output ends of the non-contact current detection devices 20 are electrically connected together and have the same electrical signal, so that the electrical signal provided by the positive output end of the non-contact current detection device 20 to the control end G of the power device 10 increases, thereby causing the current output by the power device 10 to decrease correspondingly; and when the current i output by any power device 10 decreases, the electrical signal sensed by the corresponding non-contact current detection device 20 also decreases, so that the electrical signal provided by the positive output end of the non-contact current detection device 20 to the control end G of the power device 10 decreases, thereby causing the current output by the power device 10 to increase correspondingly. Therefore, for the power device whose output current is negatively correlated with the control end signal, negative feedback compensation of the current can be finally realized through positive feedback compensation of the control end voltage according to the output current.

[0048] With reference to the foregoing Figure 2 and Figure 3 It can be understood that, for any power device 10, the power device 10 also has a first connection end S and a second connection end D, and the current flowing between the first connection end S and the second connection end D is the current i output by the power device 10. In addition, the parallel connection of the power devices 10 can be that the first connection ends S of the power devices 10 are connected together, and the second connection ends D of the power devices 10 are connected together. For example, when the power device 10 is a MOSFET, the source of the MOSFET is the first connection end S, and the drain of the MOSFET is the second connection end D.

[0049] On the basis of the foregoing embodiments, optionally, the non-contact current detection device 20 can be a current sensor based on electromagnetic induction, one of the positive polarity terminal of the induced voltage and the negative polarity terminal of the induced voltage of the current sensor is the first output end, and the other is the second output end. Specifically, the sensing coil in the current sensor senses the current on the measured line and generates an induced electromotive force, so that the voltage signal output between the first output end and the second output end of the current sensor is positively correlated with, for example, proportional to the current flowing through the measured line, and can effectively represent the measured current. For example, the electromagnetic induction coupling coefficients of the current sensors are consistent, so as to provide the same current sensing effect.

[0050] In this way, the parallel device current equalization compensation scheme based on electromagnetic induction is provided, the compensation network is established by using the current sensor based on electromagnetic induction, and the relief and compensation of the unbalanced current distribution in the parallel assembly are realized.

[0051] On the basis of the above-mentioned embodiments, optionally, the type of the non-contact current detection device 20 is various, which is described below respectively.

[0052] In an embodiment, optionally, the non-contact current detection device 20 can be an active device, and the non-contact current detection device 20 can specifically include a Hall sensor. Based on the advantages of short response time and high linearity of the Hall sensor, the effect of current equalization can be effectively improved.

[0053] In another embodiment, optionally, the non-contact current detection device 20 can be a passive device. Compared with the active element, the passive non-contact current detection device has higher tolerance to high temperature, which can effectively reduce the risk of damage of the circuit due to heat of the power device, and further improve the reliability of the circuit.

[0054] Specifically, the passive non-contact current detection device 20 can be a Rogowski coil or a current transformer. In this way, the non-contact current detection device 20 has a flexible sensing coil, which can flexibly adapt to different diameters of the measured circuit, and does not need to contact the measured circuit, and can realize high-precision current sensing. For example, a soft magnetic annular core winding can be used in the Rogowski coil, and the specific winding mode of the Rogowski coil is not limited here.

[0055] On the basis of the above-mentioned embodiments, optionally, the electromagnetic induction coupling coefficient of the current sensor is positively correlated with the preset compensation strength. The preset compensation strength is a preset change amount of the electrical signal provided to the control end of the power device when the output current of the power device changes by a unit.

[0056] In this embodiment, by selecting a suitable compensation strength and setting the electromagnetic induction coupling coefficient of the current sensor accordingly, the current equalization is finally optimized. The higher the preset compensation strength is, the greater the degree of control of the feedback of the compensation network on the control end G of the power device 10. The preset compensation strength can be preset according to actual needs, for example, the stronger the feedback ability of the compensation network is required, the greater the preset compensation strength can be set. For example, the electromagnetic induction coupling coefficient of the current sensor can be controlled by adjusting the number of turns of the sensing coil of the current sensor.

[0057] On the basis of the above-mentioned embodiments, optionally, the power device 10 can be a packaged power device or a related bare chip. The utility model embodiment has little effect on packaging, and the non-contact current detection device 20 can be packaged together with the power device 10 (for the case of internal current equalization of the module), or the non-contact current detection device 20 and the packaged power device 10 can be separately arranged on the circuit board (for the case of external current equalization between multiple devices). The different packaging cases are exemplarily described below.

[0058] In an embodiment, the power device is a packaged power device, and a control pin of the packaged power device is used as the control terminal. The power assembly further comprises a circuit board, and each packaged power device and each non-contact current detection device are disposed on the circuit board and connected through circuit traces on the circuit board. The second output terminal of the non-contact current detection device is connected to the control pin of the packaged power device through the circuit trace on the circuit board.

[0059] Specifically, the packaged power device is connected to an external circuit through pins extending out of a package shell, such as a control pin used as a control terminal, a first connection pin used as a first connection terminal, and a second connection pin used as a second connection terminal. The non-contact current detection device can be connected to the circuit trace corresponding to the first connection pin or the second connection pin of the packaged power device. The first connection terminals of the non-contact current detection devices are connected together through the circuit trace, and the second connection terminals of the non-contact current detection devices are respectively connected to the control pins of the packaged power devices through the circuit trace. In this way, current equalization compensation of device-level parallel connection can be achieved.

[0060] For example, each power device can be a TO package (Transistor Outline, transistor outline package). The first connection pins of each packaged power device can be connected to each other through the circuit trace, and the second connection pins of each packaged power device can be connected to each other through the circuit trace.

[0061] This current equalization compensation scheme can not only be applied to current equalization compensation of device-level parallel connection, but also can be applied to current equalization compensation of parallel connection of bare power chips inside a power assembly in another embodiment. Specifically, the power device is a bare power chip, the control terminal of the bare power chip is used as the control terminal, and the second output terminal of the non-contact current detection device is connected to the control terminal of the bare power chip through a bonding wire. Each bare power chip and each non-contact current detection device are collectively packaged to form a power assembly.

[0062] Specifically, the control terminal of the bare power chip is used as the control terminal, the first terminal is used as the first connection terminal, and the second terminal is used as the second connection terminal. The non-contact current detection device can be connected to the bonding wire corresponding to the first terminal or the second terminal of the bare power chip. The first connection terminals of the non-contact current detection devices can be connected to the same conductive pad through the bonding wire, and the second connection terminals of the non-contact current detection devices are respectively connected to the control terminals of the bare power chips through the bonding wire. After the connection of each bare power chip and each non-contact current detection device is completed, the connected structure is packaged to obtain a power assembly with a parallel power module. In this way, current equalization compensation of parallel connection of bare power chips inside the parallel power module can be achieved.

[0063] On the basis of the above-mentioned embodiments, optionally, the non-contact current detection device is preferably a passive device, for example, the non-contact current detection device is a passive coil, in actual application, as long as the insulation is guaranteed and the coil can be placed in a suitable position, compared with the active element which is not resistant to high temperature and needs low voltage power supply to operate normally, when the passive non-contact current detection device is used, the packaging process can be effectively simplified.

[0064] For example, the non-contact current detection device can be a PCB (Printed Circuit Board) Rogowski coil. Through the non-contact current sensor based on the printed circuit board technology, the compensation network is realized by the PCB and embedded in the parallel power module, so as to effectively realize the current equalization compensation of the parallel bare power chip in the parallel power module.

[0065] In summary, the utility model embodiment provides a kind of parallel device current equalization compensation circuit based on electromagnetic induction.For each power device, a passive non-contact current detection device based on electromagnetic induction is configured.For each power device, a passive non-contact current detection device based on electromagnetic induction is configured.The current output by each power device induces a voltage signal in the corresponding non-contact current detection device.The first output terminals of all non-contact current detection devices are connected together, and the second output terminals of each non-contact current detection device are connected to the control terminals of the corresponding power devices, thereby forming a compensation network, which effectively alleviates the current imbalance of parallel devices.The power assembly provided by the embodiment reduces the matching requirements for parallel power devices, reduces the scrap rate of parallel power devices, and reduces costs compared to the upstream solution in the related art.On the other hand, it provides more design and implementation margins for device packaging and circuit design other than current equalization, improving the overall performance of the parallel system.Compared to the downstream solution in the related art, the circuit provided by the embodiment reduces circuit complexity, and only a small cost (such as using a PCB Rogowski coil as a non-contact current detection device) is required to achieve good current equalization compensation effect, with low application cost, low process difficulty required for circuit preparation and packaging, simple and stable system structure, and improved system stability;Each non-contact current detection device is an additional feedback compensation device outside the parallel power devices, without the need to adjust the original drive structure of each power device or modify the power device driver, making the compensation network more widely applicable and compatible with various parallel assemblies;The compensation network of the utility model embodiment does not use active devices and only uses passive materials, which is naturally resistant to high temperatures of power devices and more suitable for high-temperature working environments of power devices.Therefore, the current equalization solution provided by the utility model embodiment has low cost, low process difficulty, high compatibility and high reliability, which can simply and effectively optimize the current equalization of parallel assemblies and is beneficial to implementation and application in engineering.

[0066] The utility model embodiment further provides an electronic device including the power assembly provided by any embodiment of the utility model, which has corresponding beneficial effects. Figure 4 is a structural schematic diagram of an electronic device provided by the utility model embodiment, referring to Figure 4 The power assembly includes power devices 10 and non-contact current detection devices 20.Exemplarily, the power device 10 can include a power tube Q and a protection resistor RGint connected to the control electrode of the power tube Q;One end of the protection resistor RGint serves as the control terminal of the power device 10, and the other end is connected to the control electrode of the power tube Q.

[0067] On the basis of the above-mentioned embodiments, the electronic device further comprises a driver 30 connected to the control end of each power device 10. Figure 4 The driving source Sdr is an equivalent ideal voltage source representing the output of the driver 30, and the driving resistance RGdr represents the internal resistance of the driver 30. The driving source Sdr and the driving resistance RGdr are connected in series to represent the driver 30. In the electronic device, the driver 30 can provide a driving signal to the control end of each power device 10, and each non-contact current detection device 20 can provide feedback compensation to the control end of each power device 10, so as to ensure that each power device 10 can be normally driven and work, and to achieve current sharing of each power device 10.

[0068] Further, the electronic device can further comprise a driving protection resistance RGext corresponding to each power device 10. For example, the driving protection resistance RGext is connected between one end of the driver 30 and the control end of the corresponding power device 10. The driver 30 can provide a driving signal to the control end of the power device 10 through the driving protection resistance RGext, and the other end of the driver 30 can be connected to each power device 10 to form a current loop of the driving signal of each power device 10. For example, taking a power tube Q as a MOSFET, the protection resistance RGint is connected to the gate of the power tube Q as the gate resistance of the power tube Q. The other end of the driver 30 can be connected to the source of each power tube Q. The driver 30 can provide the same driving signal to each power device 10 in parallel.

[0069] It should be understood that the above-mentioned various forms of flow can be reordered, added or deleted. For example, the steps described in the present application can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions of the present application can be achieved, which are not limited herein.

[0070] The above specific embodiments do not constitute a limitation on the scope of protection of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A power component, characterized in that, include: Multiple power devices connected in parallel; wherein the power devices control the current output by the power devices according to the electrical signal at their control terminals; A plurality of non-contact current sensing devices are provided, each corresponding to one of the power devices. The first output terminals of each non-contact current sensing device are interconnected, and the second output terminals of each non-contact current sensing device are respectively connected to the control terminals of each power device. The non-contact current sensing device is used to detect the current output by the corresponding power device, and the polarity of the second output terminal is configured such that the signal from the second output terminal acts on the control terminal, forming a negative feedback regulation of the current output by the power device.

2. The power component according to claim 1, characterized in that, The current output by the power device is positively correlated with the electrical signal at the control terminal. The first output terminal is the positive output terminal of the non-contact current detection device, and the second output terminal is the negative output terminal of the non-contact current detection device.

3. The power component according to claim 1, characterized in that, The current output by the power device is negatively correlated with the electrical signal at the control terminal. The first output terminal is the negative output terminal of the non-contact current detection device, and the second output terminal is the positive output terminal of the non-contact current detection device.

4. The power component according to any one of claims 1-3, characterized in that, The power device is a voltage-controlled power device or a current-controlled power device.

5. The power component according to claim 1, characterized in that, The non-contact current sensing device is a passive device.

6. The power component according to claim 5, characterized in that, The non-contact current sensing device includes a Rogowski coil or a current transformer.

7. The power component according to claim 1, characterized in that, The non-contact current detection device includes a Hall sensor.

8. The power component according to claim 1, characterized in that, The non-contact current detection device is a current sensor based on electromagnetic induction; the electromagnetic induction coupling coefficient of the current sensor is positively correlated with the preset compensation strength, and the preset compensation strength is the preset change amount of the electrical signal that needs to be provided to the control terminal of the power device when the current output by the power device changes by one unit. The electromagnetic induction coupling coefficients of all the current sensors are the same.

9. The power component according to claim 1, characterized in that, The power device is a packaged power device, and the control pin of the packaged power device serves as the control terminal. The power component further includes: a circuit board; each of the packaged power devices and each of the non-contact current sensing devices are disposed on the circuit board, and the second output terminal of the non-contact current sensing device is connected to the control pin of the packaged power device through the circuit trace on the circuit board. or, The power device is an unpackaged bare power chip, the control electrode of the bare power chip serves as the control terminal, and the second output terminal of the non-contact current sensing device is connected to the control electrode of the bare power chip via a bonding wire; each bare power chip and each non-contact current sensing device are jointly packaged to form the power assembly.

10. An electronic device, characterized in that, include: The power component according to any one of claims 1-9.

11. The electronic device according to claim 10, characterized in that, Also includes: The driver is connected to the control terminal of each of the power devices.

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