IPM and current protection method thereof, and IPM control system

Abstract

The present application provides an embodiment belonging to integrated circuit technology, providing an IPM and its current protection method, and an IPM control system, wherein the gate drive circuit includes a detection circuit, a high-side drive chip and a first power switch element, a low-side drive chip and a second power switch element; wherein the high-side drive chip transmits a first drive signal to the first power switch element, and the first drive signal is used to control the current flow in the first main current path, driving the first power switch element to be turned on or off; the detection circuit detects the potential change of the second end corresponding to the main current path of the first power switch element, and transmits a first cut-off signal to the high-side drive chip according to the potential change of the second end, so that the first power switch element is placed in a current protection state. The present application can quickly identify the abnormal state of the high-side power switch element and provide overcurrent protection.

Description

Technical Field

[0001] The embodiments of the present application relate to integrated circuit technology, and more specifically, to an IPM and a current protection method thereof, and an IPM control system. Background Art

[0002] Intelligent Power Module (IPM) is commonly used in three-phase inverter circuits such as household appliances, industrial machines and automotive products. Since IPM is often used under high voltage and high current, when an abnormal state occurs (such as load short circuit, etc.), excessive energy (current) will cause damage to the power switch element. Therefore, it is necessary to timely protect the power switch element from current when the power switch element is in an abnormal state.

[0003] IPM includes a power switch element on the high-voltage side (hereinafter referred to as the high side) and a power switch element on the low-voltage side (hereinafter referred to as the low side). When the driver chip (Integrated Circuit Chip, IC) in the IPM is separated at the high side and the low side, the abnormal state detection on the high side usually relies on the external microcomputer control output corresponding control signal. The delay time from the detection to the actual power switch element power-on stop is long, which can easily lead to damage due to exceeding the damage tolerance range of the power switch element. Summary of the invention

[0004] The embodiments of the present application provide an IPM and a current protection method thereof, and an IPM control system, which are used to solve the problem of damage to high-side power switch elements caused by excessive current due to abnormal conditions such as load short circuit.

[0005] In the first aspect, the present application provides an intelligent power module IPM, comprising a detection circuit, a high-side driver chip and a first power switch element, a low-side driver chip and a second power switch element; the first end and the second end of the first power switch element constitute a first main current path from the first end to the second end, the third end of the first power switch element is used to control the switch of the first main current path, the fourth end and the fifth end of the second power switch element constitute a second main current path from the fourth end to the fifth end, and the sixth end of the second power switch element is used to control the switch of the second main current path; wherein the second end is electrically connected to the fourth end, so that the first power switch element and the second power switch element are connected in series; the high-side driver chip is electrically connected to the third end of the first power switch element, and is used to transmit a first drive signal to the first power switch element, and the first end of the second power switch element is used to transmit a first drive signal to the first power switch element. a driving signal for controlling the current flow in the first main current path and driving the first power switch element to be turned on or off; the low-side driving chip is electrically connected to the sixth end of the second power switch element and is used to transmit a second driving signal to the second power switch element, the second driving signal is used to control the current flow in the second main current path and drive the second power switch element to be turned on or off; the detection circuit, one end of which is connected to the high-side driving chip and the other end of which is connected to the wire between the first power switch element and the second power switch element, is used to detect the potential change of the second end of the first power switch element, and transmit a first cut-off signal to the high-side driving chip according to the potential change of the second end, the first cut-off signal is used to cut off the first power switch element, so that the first power switch element is placed in a current protection state.

[0006] In one embodiment, the first power switch element and the second power switch element respectively include at least one of the following: an insulated gate bipolar transistor IGBT tube, a first metal oxide semiconductor field effect transistor MOS tube, and a bipolar transistor BJT tube.

[0007] In one embodiment, the first power switch element and / or the second power switch element is an IGBT tube, the first end and / or the fourth end are the collector of the IGBT tube, the second end and / or the fifth end are the emitter of the IGBT tube, and the third end and / or the sixth end are the gate of the IGBT tube; or, the first power switch element and / or the second power switch element is a first MOS tube, the first end and / or the fourth end are respectively the drain of the first MOS tube, the second end and / or the fifth end are respectively the source of the first MOS tube, and the third end and / or the sixth end are the gate of the first MOS tube; or, the first power switch element and / or the second power switch element is a BJT tube, the first end and / or the fourth end are respectively the collector of the BJT tube, the second end and / or the fifth end are respectively the emitter of the BJT tube, and the third end and / or the sixth end are the base of the BJT tube.

[0008] In one embodiment, it also includes a third power switch element and a fourth power switch element, the seventh end and the eighth end of the third power switch element constitute a third main current path from the seventh end to the eighth end, the ninth end of the third power switch element is used to control the switch of the third main current path, the tenth end and the eleventh end of the fourth power switch element constitute a fourth main current path from the tenth end to the eleventh end, and the twelfth end of the fourth power switch element is used to control the switch of the fourth main current path; wherein the eighth end is electrically connected to the tenth end to form a second connection structure between the third power switch element and the fourth power switch element; the high-side driver chip is also electrically connected to the ninth end of the third power switch element, and is used to transmit a third drive signal to the third power switch element, and the third drive signal is used to control the The current in the third main current path flows, and drives the third power switch element to be turned on or off; the low-side driver chip is also electrically connected to the twelfth terminal of the fourth power switch element, and is used to transmit a fourth drive signal to the fourth power switch element, and the fourth drive signal is used to control the current flow in the fourth main current path, and drive the fourth power switch element to be turned on or off; the detection circuit, one end of which is connected to the high-side driver chip, and the other end of which is connected to the wire between the third power switch element and the fourth power switch element, is used to detect the potential change of the ninth terminal of the third power switch element, and transmit a second cut-off signal to the high-side driver chip according to the potential change, and the second cut-off signal is used to cut off the third power switch element, so that the third power switch element is placed in a current protection state.

[0009] In one embodiment, the present invention further comprises a fifth power switch element and a sixth power switch element, wherein the thirteenth terminal and the fourteenth terminal of the fifth power switch element constitute a fifth main current path from the thirteenth terminal to the fourteenth terminal, the fifteenth terminal of the fifth power switch element is used to control the switch of the fifth main current path, the sixteenth terminal and the seventeenth terminal of the sixth power switch element constitute a sixth main current path from the sixteenth terminal to the seventeenth terminal, and the eighteenth terminal of the sixth power switch element is used to control the switch of the sixth main current path; wherein the fourteenth terminal is electrically connected to the sixteenth terminal to form a third connection structure between the fifth power switch element and the sixth power switch element; the high-side driver chip is also electrically connected to the fifteenth terminal of the fifth power switch element to transmit a fifth drive signal to the fifth power switch element, and the fifth drive signal Used to control the current flow in the fifth main current path and drive the fifth power switch element to be turned on or off; the low-side driver chip is also electrically connected to the eighteenth terminal of the sixth power switch element, and is used to transmit a sixth drive signal to the sixth power switch element, and the sixth drive signal is used to control the current flow in the sixth main current path and drive the sixth power switch element to be turned on or off; the detection circuit, one end of which is connected to the high-side driver chip, and the other end of which is connected to the wire between the fifth power switch element and the sixth power switch element, is used to detect the potential change of the fourteenth terminal of the fifth power switch element, and transmit a third cut-off signal to the high-side driver chip according to the potential change, and the third cut-off signal is used to cut off the fifth power switch element, so that the fifth power switch element is placed in a current protection state.

[0010] In one embodiment, the detection circuit is integrated inside the high-side driver chip; one end of the detection circuit is specifically connected to the high-side driver module of the high-side driver chip, and the other end of the detection circuit is specifically connected to the high-side floating power return terminal of the high-side driver chip, so that the detection circuit is connected to the wire connected between the first power switch element and the second power switch element through the high-side floating power return terminal to detect the potential change of the second end of the first power switch element, and transmit the first cut-off signal to the high-side driver module according to the potential change of the second end; the high-side driver module, one end of which is respectively connected to the detection circuit and the other end of which is connected to the first power switch element, is used to drive the first power switch element to be turned on or off according to the first drive signal when the first cut-off signal is not received; or, when the first cut-off signal is received, the first power switch element is cut off according to the first cut-off signal, so that the first power switch element is placed in a current protection state.

[0011] In one embodiment, the detection circuit includes a constant voltage source circuit, a current control circuit and a potential detection circuit; wherein the current control circuit includes a current control element and an operational amplifier electrically connected to the current control element; the current control circuit, one end of which is connected to the wire between the first power element and the second power element through the current control element, and the other end of which is connected to the constant voltage source circuit through the operational amplifier; the potential detection circuit, one end of which is connected to the current control element, and the other end of which is connected to the high-side driver chip; when the potential of the second end of the first power switch element changes, the operational amplifier outputs a corresponding level signal to the current control element based on the constant voltage source circuit to adjust the resistance of the current control element and provide a constant current for the current path; the potential detection circuit detects the potential change of the current control element after adjusting the resistance, and detects the potential change of the second end according to the potential change.

[0012] In one embodiment, the constant voltage source circuit includes a first constant voltage source; the current control element is a second MOS tube, and the current control circuit also includes a first resistor and a second resistor; the first resistor, one end of which is connected to the wire between the first power switch element and the second power switch element, and the other end of which is connected to the drain of the second MOS tube; the second resistor, one end of which is connected to the source of the second MOS tube, and the other end of which is connected to the ground; the operational amplifier, a first input end of which is connected to the wire between the source of the second MOS tube and the second resistor; a second input end of which is connected to the first constant voltage source; an output end of which is connected to the wire between the gate of the second MOS tube and the potential detection circuit; when the gate of the second MOS tube receives the level signal output by the operational amplifier, the potential of the gate of the second MOS tube is controlled to be turned on by rising potential or to be turned off by falling potential, so as to be adjusted to the resistance value.

[0013] In one implementation, the potential detection circuit includes a third resistor and a fourth resistor; one end of the third resistor is connected to the gate of the second MOS tube, and the other end is connected to the fourth resistor; the output end of the operational amplifier is specifically connected to the wire between the gate of the second MOS tube and the third resistor; the high-side driver chip is specifically connected to the wire between the third resistor and the fourth resistor, so that the detection circuit is connected to the high-side driver chip;

[0014] Wherein, the potential change of the connection point of the high-side driver chip connected to the wire between the third resistor and the fourth resistor corresponds to the potential change of the gate, and the potential change of the gate is used to determine the potential change of the second end. In one embodiment, the potential detection circuit also includes an inverter; the inverter has an input end connected to the wire between the third resistor and the fourth resistor, and an output end connected to the high-side driver chip, so that the high-side driver chip is connected to the wire between the third resistor and the fourth resistor through the inverter, and the inverter is used to invert the potential change of the gate to obtain the first cut-off signal, and output the first cut-off signal to the high-side driver chip.

[0015] In one embodiment, the constant voltage source circuit also includes a second constant voltage source; the operational amplifier, whose third input terminal is connected to the second constant voltage source, and whose fourth input terminal is connected to the ground terminal, so that its output terminal outputs the level signal corresponding to the second constant voltage source or the ground terminal to the current control element.

[0016] In a second aspect, an embodiment of the present application provides a current protection method for an IPM, the IPM comprising a detection circuit, a high-side driver chip and a first power switch element, a low-side driver chip and a second power switch element; the first end and the second end of the first power switch element constitute a first main current path from the first end to the second end, the third end of the first power switch element is used to control the switch of the first main current path, the fourth end and the fifth end of the second power switch element constitute a second main current path from the fourth end to the fifth end, and the sixth end of the second power switch element is used to control the switch of the second main current path; wherein the second end is electrically connected to the fourth end so that the first power switch element and the second power switch element are connected in series, the method comprising: the high-side driver chip transmits a first drive signal to the third end of the first power element to drive the first power switch element to be turned on or off based on the first drive signal; the low-side driver chip transmits a second drive signal to the sixth end of the second power element to drive the second power switch element to be turned on or off based on the second drive signal;

[0017] The detection circuit detects the potential change of the second end of the first power switch element, and transmits a first cut-off signal to the high-side driver chip according to the potential change of the second end, wherein the first cut-off signal is used to cut off the first power switch element, so that the first power switch element is placed in a current protection state.

[0018] In a third aspect, an embodiment of the present application provides a computer-readable storage medium, on which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, the current protection method of the IPM is implemented.

[0019] In a fourth aspect, an embodiment of the present application provides an IPM control system, the IPM and a load device, and the load device is electrically connected to the first power switch element.

[0020] The IPM and current protection method thereof, and the IPM control system provided in the embodiments of the present application are configured with a detection circuit, one end of which is connected to the high-side driver chip, and the other end of which is connected to the output end (i.e., Vs potential) of the main current path of the power switch element. The detection circuit is used to detect the Vs potential of the power switch element. S potential changes, and according to the V S The potential change transmits a cut-off signal to the high-side driver chip to cut off the power switch element, so that the first power switch element is placed in a current protection state. This process detects the Vs potential change of the high-side power switch element and identifies the abnormal state of the high-side power switch element, without combining the low-side protection circuit and the protection signal of the microcontroller, and can quickly put the high-side power switch element into a current protection state; and when the detection circuit is integrated in the high-side driver chip, no additional terminals are required, which reduces the hardware development cost of the high-side gate driver chip and meets the packaging miniaturization requirements of the high-side gate driver chip. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the implementation methods in the embodiments of the present application or the related technologies, the following is a brief introduction to the drawings required for use in the embodiments or the related technology descriptions. Obviously, the drawings described below are some embodiments of the present application, and a person skilled in the art can also obtain other drawings based on these drawings.

[0022] Figure 1 One of the structural diagrams of the IPM provided in the embodiment of the present application;

[0023] Figure 2 A schematic diagram of the structure of an IPM provided in another embodiment of the present application;

[0024] Figure 3 A schematic diagram of the structure of an IPM provided in yet another embodiment of the present application;

[0025] Figure 4 A schematic diagram of the structure of an IPM provided in yet another embodiment of the present application;

[0026] Figure 5 The second structural diagram of the IPM provided in the embodiment of the present application;

[0027] Figure 6 for Figure 1 Schematic diagram of the structure of the detection circuit;

[0028] Figure 7 It is a structural schematic diagram of a high-side driver chip in the related art;

[0029] Figure 8 This is a schematic diagram of the structure of the high-side driver chip in the embodiment of the present application;

[0030] Fig. 9 A schematic diagram of a flow chart of current protection of an IPM provided in an embodiment of the present application;

[0031] Fig.10 An IPM control system is provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the purpose, implementation mode and advantages of the present application clearer, the exemplary implementation mode of the present application will be clearly and completely described below in conjunction with the drawings in the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0033] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their ordinary and common meanings.

[0034] In addition, the terms "include" and "have" and any variations thereof are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to those components expressly listed but may include other components not expressly listed or inherent to such products or devices.

[0035] The power switching elements used in IPM, such as insulated gate bipolar transistors (IGBT), have the advantages of high current density, low saturation voltage and high voltage resistance of giant transistors (GTR), as well as the advantages of high input impedance, high switching frequency and low driving power of field effect transistors (MOSFET). IPM integrates logic, control, detection and protection circuits (set in the low-side driver chip) internally, which is easy to use. It not only reduces the size and development time of the system, but also greatly enhances the reliability of the system. It adapts to the development direction of today's power devices - modularization, composite and power integrated circuits (PIC), so it is often used in high current and high voltage circuit structures. When the load is abnormal, such as load short circuit, the power switch element will flow through an excessive current exceeding the rated value, thereby causing damage to the power switch element.

[0036] In the related art, shunt resistors or other electronic components are mainly used to detect such excessive current, and the power switching element is stopped from being powered on to prevent damage. Specifically, in the IPM configuration, when the power switching element driver IC is separated into a high side and a low side, a detection circuit is installed on the driver IC at the low side end, and a shunt resistor is applied externally to detect and stop the operation of the low-side power switching element. In this case, the following problems will arise: when the power switching element on the low side is short-circuited or the load is short-circuited, the control microcomputer usually sends a cut-off control command to the high-side driver IC, and sends a cut-off signal to the low-side driver IC, but due to the delay time, the excessive current of the high-side power element cannot be prevented, which will cause the problem of damage caused by exceeding the overcurrent tolerance of the power switching element. In addition, in an abnormal state where the shunt resistor is not passed (for example, when the output terminal part and GND are short-circuited), the abnormality of the shunt resistor will not be detected.

[0037] In response to the above problems, the technical personnel of the present application have discovered through research that, as a feature of the power switching element, when an excessive current exceeding the rated value flows, the potential difference of the power switching element expands rapidly when the specified current is exceeded. This is usually when the state where the power supply and potential are almost equal during operation changes to an abnormal state (load short circuit), that is, when the current is too large, which means that the potential drops sharply. Therefore, the above potential change can be detected in the driver IC, and by turning off or cutting off the power switching element, it can be used as a solution to stop within the current bearing capacity time of the power switching element, thereby solving the above-mentioned power switching element damage problem. Specifically, the embodiment of the present application provides an IPM and its current protection method, and an IPM control system, by setting a detection circuit, one end of which is connected to the high-side driver chip, and the other end of which is connected to the output end of the main current path of the power switching element (i.e., the Vs potential), and the detection circuit is used to detect the Vs potential of the power switching element. S potential changes, and according to the V S The potential change transmits a cut-off signal to the high-side driver chip to cut off the power switch element, so that the first power switch element is placed in a current protection state. This process detects the Vs potential change of the high-side power switch element and identifies the abnormal state of the high-side power switch element, without combining the low-side protection circuit and the protection signal of the microcontroller, and can quickly put the high-side power switch element into a current protection state; and when the detection circuit is integrated in the high-side driver chip, no additional terminals are required, which reduces the hardware development cost of the high-side gate driver chip and meets the packaging miniaturization requirements of the high-side gate driver chip.

[0038] The technical solution of the present application is described in detail below in conjunction with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0039] Figure 1 is a schematic diagram of the structure of an IPM provided by an embodiment of the present application, such as Figure 1As shown, the IPM300 includes a detection circuit 310, a high-side driver chip 320, a first power switch element 330, a low-side driver chip 340, and a second power switch element 350; the first end 1 and the second end 2 of the first power switch element 330 constitute a first main current path from the first end 1 to the second end 2, the third end 3 of the first power switch element 330 is used to control the switch of the first main current path, the fourth end 4 and the fifth end 5 of the second power switch element 350 constitute a second main current path from the fourth end 4 to the fifth end 5, and the sixth end 6 of the second power switch element 350 is used to control the switch of the second main current path; wherein the second end 2 is electrically connected to the fourth end 4, so that the first power switch element 330 and the second power switch element 350 are connected in series; the high-side driver chip 320 is electrically connected to the third end 3 of the first power switch element 330, and is used to transmit a first drive signal to the first power switch element 330, so that ... The first driving signal is used to control the current flow in the first main current path and drive the first power switch element 330 to be turned on or off; the low-side driving chip 340 is electrically connected to the sixth end 6 of the second power switch element 350, and is used to transmit a second driving signal to the second power switch element 350, and the second driving signal is used to control the current flow in the second main current path and drive the second power switch element 350 to be turned on or off; the detection circuit 310, one end of which is connected to the high-side driving chip 320, and the other end of which is connected to the wire between the first power switch element 330 and the second power switch element 350, is used to detect the potential change of the second end 2 of the first power switch element 330, and transmit a first cut-off signal to the high-side driving chip 320 according to the potential change of the second end 2, and the first cut-off signal is used to cut off the first power switch element 330, so that the first power switch element 330 is placed in a current protection state.

[0040] In this embodiment, the high-side driver chip and the first power switch element, the low-side driver chip and the second power switch element form a half-bridge circuit and are connected to a load. The first power switch element and the second power switch element are driven by the corresponding driver chip to turn on or off, respectively, thereby driving the load.

[0041] In this embodiment, when the load connected to the first power switch element (i.e., the high-side power element) is abnormal, the Vs potential of the high-side power switch element (i.e., the potential of the second end 2 of the high-side power element, more specifically, the potential of the potential point connected between the second end 2 and the fourth end 4 of the low-side power element and connected to the load, which corresponds to the output of the high-side power switch element) will change. For example, under normal working conditions, the Vs potential is a high potential (e.g., 20V, which can be determined according to the adaptability of actual applications). When the load is short-circuited, the current increases sharply, causing the Vs potential to drop sharply. In this embodiment, a detection circuit is set to detect By measuring the potential change of Vs, the abnormal state of the high-side power switch element can be quickly determined, and a cut-off signal can be transmitted to the high-side driver chip in real time to cut off the high-side power switch element (for example, the transmission of the drive signal can be blocked, or the drive signal can be pulled down by sending a low-level signal, the high-side power switch element can be turned off by cutting off the power supply of the main current path, or the high-side power switch element can be placed in a current protection state by cutting off the power supply, etc., and the specific method is not particularly limited in this embodiment), without transmitting the protection signal to the high side through the low-side protection circuit and the control microcomputer, and causing damage to the high-side power switch element due to problems such as signal delay.

[0042] In this embodiment, the detection circuit detects the Vs potential change of the first power switching element. The Vs potential change can be defined as a change within a certain potential range. For example, a person skilled in the art can determine a normal potential change range (for example, within 12V, or other ranges) in combination with practical applications and prior art (or based on a large number of experiments). If the normal potential change range is exceeded (such as the potential drops from 13V to 0.5V), it indicates that the current Vs potential change is abnormal (i.e., a sharp change), that is, the high-side power switching element is in an abnormal state.

[0043] In this embodiment, the other end of the detection circuit can be connected to the input end of the high-side (gate) driver chip. For example, the first power switch element can be connected to the high-side driver chip by combining the cut-off signal with the HIN signal as the drive signal. After the high-voltage side driver chip receives the cut-off signal, even if the drive signal is used to drive the IGBT to turn on, the first power switch element will be turned off in combination with the cut-off signal, and the operation of the first power switch element will be stopped to be placed in a current protection state. In some embodiments, the cut-off signal can also be used to cut off the power supply of the high-side driver chip for a period of time, thereby stopping the operation of the first power switch element and placing it in a current protection state. In some embodiments, the first power switch element can also be turned off by outputting a low-level signal to the high-side driver chip. In some embodiments, a protection circuit can also be provided, one end of which is connected to the detection circuit and the other end is connected to the high-side driver chip, wherein the detection circuit is connected to the high-side driver chip through the protection circuit, and the shutdown logic (such as shutdown time, shutdown method, etc.) and power-on recovery logic (such as recovery time, recovery method, etc.) are set in the protection circuit. The protection circuit transmits a cutoff signal to the high-side driver chip according to the shutdown logic, and when the power-on recovery logic is met, the high-side driver chip is restarted to transmit a normal drive signal to drive the high-side power switch element to be turned on / off for normal operation.

[0044] In this embodiment, the first power switch element 330 can be any one or a combination of an insulated gate bipolar transistor IGBT tube, a first metal oxide semiconductor field effect transistor MOS tube, and a bipolar transistor BJT tube; correspondingly, the second power switch element 350 can be any one or a combination of an insulated gate bipolar transistor IGBT tube, a first metal oxide semiconductor field effect transistor MOS tube, and a bipolar transistor BJT tube.

[0045] It can be understood that IGBT, MOSFET and BJT are all common semiconductor devices, BJT (bipolar transistor). Among them, BJT is a current-controlled device that works based on the diffusion and drift principles of carriers (electrons and holes). BJT has three pins: emitter, base and collector. The current between the collector and the emitter is controlled by the base current. The main types of BJT are NPN and PNP; MOSFET is a voltage-controlled device that uses voltage to control the flow of current. MOSFET includes source, drain and gate. Its working principle is to control the flow of charge carriers in the channel by applying voltage between the gate and the source. MOSFET mainly includes enhancement MOS tubes and depletion MOS tubes;

[0046] IGBT combines the high current carrying capacity of BJT and the high switching speed of MOSFET. It includes three pins: emitter, gate and collector. Its working principle is to use MOSFET to control the conduction and cutoff of BJT.

[0047] In some embodiments, in addition to the above-mentioned types of power elements, the first power switch element or the second power element may also use other types of power elements according to different application scenarios, which is not particularly limited in this embodiment.

[0048] Optionally, the first power switch element 330 and the second power switch element 350 may be transistors of the same type or different types, which is not particularly limited in this embodiment.

[0049] In one example, the first power switch element 330 and / or the second power switch element 350 is an IGBT tube, the first end 1 and / or the fourth end 4 is the collector of the IGBT tube, the second end 2 and / or the fifth end 5 is the emitter of the IGBT tube, and the third end 3 and / or the sixth end 6 is the gate of the IGBT tube.

[0050] In this example, the first power switching element may be an IGBT tube, and the second power switching element may be other transistors, such as a MOS tube or a BJT tube, etc.; or the second power switching element is an IGBT tube, and the first power switching element is other transistors, such as a MOS tube or a BJT tube, etc.; or the first power switching element and the second power switching element are both IGBT tubes.

[0051] Among them, when the first power switching element is an IGBT, the potential of the second end 2 detected by the detection circuit, that is, the emitter potential of the IGBT, increases sharply due to the abnormal load condition, while the emitter potential of the IGBT drops sharply. By detecting the emitter potential, the circuit abnormality can be quickly detected.

[0052] In another example, the first power switching element and / or the second power switching element is a first MOS tube, the first end 1 and / or the fourth end 4 are respectively the drains of the first MOS tube, the second end 2 and / or the fifth end 5 are respectively the sources of the first MOS tube, and the third end 3 and / or the sixth end 6 are respectively the gates of the first MOS tube.

[0053] In this example, the first power switch element may be a MOS tube, and the second power switch element may be other transistors, such as an IGBT tube or a BJT tube; or the second power switch element is a MOS tube, and the first power switch element is other transistors; or the first power switch element and the second power switch element are both MOS tubes.

[0054] When the first power switch element is a MOS tube, the potential of the second end 2 detected by the detection circuit, that is, the source potential of the MOS tube, has a detection principle similar to that of the emitter potential of the IGBT, which will not be described in detail here.

[0055] It should be noted that, in this embodiment, the first MOS transistor and the second MOS transistor are only used to distinguish similar objects and have no other meanings. The first MOS transistor and the second MOS transistor adopt the same MOS transistor structure.

[0056] In another example, the first power switching element and / or the second power switching element is a BJT tube, the first end 1 and / or the fourth end 4 are respectively the collectors of the BJT tube, the second end 2 and / or the fifth end 5 are the emitters of the first MOS tube, and the third end 3 and / or the sixth end 6 are the bases of the IGBT tube.

[0057] In this example, the first power switching element may be a BJT tube, and the second power switching element may be other transistors, such as an IGBT tube or a MOS tube, etc.; or the second power switching element is a BJT tube, and the first power switching element is other transistors; or the first power switching element and the second power switching element are both BJT tubes.

[0058] When the first power switch element is a BJT tube, the potential of the second end 2 detected by the detection circuit, that is, the emitter circuit of the BJT tube, has a detection principle similar to that of the IGBT emitter potential, which will not be described in detail here.

[0059] In the above embodiment, the potential detection is performed on the high-side power switch element in the half-bridge circuit, and overcurrent protection is implemented. The circuit protection for the high-side power switch element in the full-bridge circuit and the three-phase bridge circuit is described below:

[0060] Figure 2 FIG. 4 shows a schematic diagram of the structure of an IPM provided by another embodiment of the present application. Figure 2 In addition to the above Figure 1In addition to the circuit elements shown, a third power switch element 360 and a fourth power switch element 370 may also be included, wherein the seventh end 7 and the eighth end 8 of the third power switch element 360 constitute a third main current path from the seventh end 7 to the eighth end 8, the ninth end 9 of the third power switch element 360 is used to control the switch of the third main current path, the tenth end 10 and the eleventh end 11 of the fourth power switch element 370 constitute a fourth main current path from the tenth end 10 to the eleventh end 11, and the twelfth end 12 of the fourth power switch element 370 is used to control the switch of the fourth main current path; wherein the eighth end 8 is electrically connected to the tenth end 10, so that the third power switch element 360 and the fourth power switch element 370 are connected in series; the high-side driver chip 320 is also electrically connected to the ninth end 9 of the third power switch element, and is used to transmit a third drive signal to the third power switch element, and the third drive signal is used to control The low-side driver chip 340 is also electrically connected to the twelfth terminal 12 of the fourth power switch element 370, and is used to transmit a fourth drive signal to the fourth power switch element 370, and the fourth drive signal is used to control the current flow in the fourth main current path and drive the fourth power switch element 370 to be turned on or off; the detection circuit 310, one end of which is connected to the high-side driver chip 320, and the other end of which is connected to the wire between the third power switch element 360 and the fourth power switch element 370, and is used to detect the potential change of the ninth terminal 9 of the third power switch element 360, and transmit a second cut-off signal to the high-side driver chip 320 according to the potential change, and the second cut-off signal is used to cut off the third power switch element 360, so that the third power switch element is placed in a current protection state.

[0061] Further, the low-side driver chip drives the fourth power switch element to be turned on or off based on the fifth drive signal.

[0062] This method can provide current protection for the high-side power switch elements (the first power switch element and the third power switch element) in the full-bridge circuit, effectively reducing the time delay of implementing circuit protection for the high-side power switch elements based on the low-side driver chip.

[0063] Figure 3 FIG. 4 shows a schematic diagram of the structure of an IPM provided by another embodiment of the present application. Figure 3As shown, it can also include a fifth power switch element 380 and a sixth power switch element 390, the thirteenth terminal 13 and the fourteenth terminal 14 of the fifth power switch element 380 constitute a fifth main current path from the thirteenth terminal 13 to the fourteenth terminal 14, the fifteenth terminal 15 of the fifth power switch element 380 is used to control the switch of the fifth main current path, the sixteenth terminal 16 and the seventeenth terminal 17 of the sixth power switch element 390 constitute a sixth main current path from the sixteenth terminal 16 to the seventeenth terminal 17, and the eighteenth terminal 18 of the sixth power switch element 390 is used to control the switch of the sixth main current path; wherein the fourteenth terminal 14 is electrically connected to the sixteenth terminal 16, so that the fifth power switch element 380 and the sixth power switch element 390 are connected in series; the high-side driver chip 320 is also electrically connected to the fifteenth terminal 15 of the fifth power switch element 380, and is used to transmit a fifth drive signal to the fifth power switch element 380, and the fifteenth terminal 15 of the fifth power switch element 380 ... The fifth driving signal is used to control the current flow in the fifth main current path and drive the fifth power switch element 380 to be turned on or off; the low-side driving chip 340 is also electrically connected to the eighteenth terminal 18 of the sixth power switch element 390, and is used to transmit a sixth driving signal to the sixth power switch element 390, and the sixth driving signal is used to control the current flow in the sixth main current path and drive the sixth power switch element 390 to be turned on or off; the detection circuit 310, one end of which is connected to the high-side driving chip 320, and the other end of which is connected to the wire between the fifth power switch element 380 and the sixth power switch element 390, is used to detect the potential change of the fourteenth terminal 14 of the fifth power switch element 380, and transmit a third cut-off signal to the high-side driving chip 320 according to the potential change, and the third cut-off signal is used to cut off the fifth power switch element 380, so that the fifth power switch element is placed in a current protection state.

[0064] Further, the low-side driver chip drives the sixth power switch element to be turned on or off based on the sixth drive signal.

[0065] This method provides current protection for the three power switch elements (the first power switch element, the third power switch element and the fifth power switch element) on the high side of the three-phase bridge circuit, effectively reducing the delay of circuit protection of the high-side power switch element based on the low-side driver chip.

[0066] Figure 4A structural schematic diagram of an IPM provided by another embodiment of the present application is shown. On the basis of the above embodiment, taking into account the demand for miniaturization of IPM packaging, this embodiment integrates the detection circuit inside the high-side driver chip of the IPM, and multiplexes the high-side floating power supply return terminal of the high-side driver chip to detect the above-mentioned potential change of the high-side power switch element and transmit it to the high-side driver module. In an abnormal state, rapid current protection of the high-side power switch element can be achieved. Specifically, the detection circuit 310 in this embodiment is integrated inside the high-side driver chip 320; wherein the high-side driver chip 320 includes a signal input terminal 321, a high-side driver module 322 and a high-side floating power return terminal 323; it can be understood that the signal input terminal 321 is used to receive a first drive signal; the detection circuit 310, one end of which is specifically connected to the high-side driver module 322 of the high-side driver chip 320, and the other end of which is specifically connected to the high-side floating power return terminal 323 of the high-side driver chip 320, so that the detection circuit 310 is connected to the first power switch element 330 and the second power switch element 350 through the high-side floating power return terminal 323. A wire connected between the two ends to detect the potential change (Vs) of the second end of the first power switch element 330, and transmit the first cut-off signal to the high-side driving module 322 according to the potential change of the second end; the high-side driving module 322, one end of which is respectively connected to the detection circuit 310, and the other end of which is connected to the first power switch element 330, is used to drive the first power switch element 330 to be turned on or off according to the first drive signal when the first cut-off signal is not received; or, when the first cut-off signal is received, the first power switch element 330 is powered on according to the first cut-off signal, so that the first power switch element is placed in a current protection state.

[0067] It can be understood that the high-side driving module in this embodiment can be a gate driving circuit (such as the high-side power switch element is an IGBT, and in other embodiments it can also be other driving circuits, which are not listed one by one in this embodiment). In this embodiment, when the high-side driving chip (or high-side driving module) receives the cut-off signal, it cuts off the power supply of the high-side power switching element according to the cut-off signal and puts it in a current protection state. Regardless of whether the driving signal is a signal that turns on or off the high-side power switching element, the high-side power switching element will not be operated, which can effectively avoid the problem of damage to the high-side power switching element due to abnormal conditions. In other words, when the high-side driving module receives a mixed signal of the driving signal and the cut-off signal, since the cut-off signal puts the power switching element in the current protection state, even if the driving signal is a conduction signal, the high-side driving module will no longer drive the power switching element to be turned on.

[0068] By adopting the above technical solution, the detection circuit is integrated into the high-side driver chip, and the Vs signal of the high-side power switch element is detected by reusing the high-side floating power return terminal of the high-side driver chip without adding additional terminals, which effectively reduces the hardware development cost and meets the packaging miniaturization requirements of the gate driver chip. In some embodiments, the above technical solution can also be applied in a full-bridge circuit or a three-phase bridge circuit, and the principle is similar, which will not be described in detail here.

[0069] In an optional implementation of an embodiment, the detection circuit 310 may use a constant current source circuit structure for detection, and utilize the stability of the constant current source circuit to improve the detection accuracy of the Vs potential. Figure 5 As shown, the detection circuit 310 includes a constant voltage source circuit 311, a current control circuit 312 and a potential detection circuit 313; wherein the current control circuit 312 includes a current control element 3121 and an operational amplifier 3122 electrically connected to the current control element 3121; one end of the current control circuit 312 is connected to the wire between the first power switch element 330 and the second power switch element 350 through the current control element 3121 ( Figure 6 31 shows that the current control element 3121 is connected to the second end of the first power switch element 330, and the potential of the second end corresponds to the potential of the connection point between the first power switch element 330 and the second power switch element 350, which is used to detect the Vs potential of the first power switch element 330, and the other end of which is connected to the constant voltage source circuit 311 through the operational amplifier 3122; the potential detection circuit 313, one end of which is connected to the current control element 3121, and the other end of which is connected to the high-side drive chip 320;

[0070] When the potential of the second end 2 of the first power switch element 330 (i.e., the Vs potential) changes, the operational amplifier 3122 outputs a corresponding level signal to the current control element 3121 based on the constant voltage source circuit 311 to adjust the resistance of the current control element 3121 and provide a constant current for the current path; the potential detection circuit 313 detects the gate potential change of the current control element 3121 after the resistance is adjusted, and detects the potential change of the second end 2 according to the gate potential change.

[0071] In this embodiment, the current control circuit is connected to the second end of the first power switching element (for example, the emitter of the IGBT), wherein the current control circuit is connected to the constant voltage source circuit, and the current in the current path always remains constant. When the emitter potential changes, the potential of the current control element in the current control circuit will also change to keep the current in the entire current path constant. The Vs potential can be detected by detecting the potential change of the current control element (which can be a switching tube such as a MOS tube or other transistor or other current control element). Specifically, the operational amplifier provides a corresponding level signal (high / low level signal) for the current control circuit based on a constant voltage source circuit, wherein the constant voltage source circuit can use one or more constant voltage sources to provide a reference voltage, so that the current control circuit receives the level signal output by the operational amplifier based on the constant voltage source circuit, and controls the current in the entire current path to remain constant by adjusting the resistance value of the current control element (resistance increases, current decreases), the current control element is connected to the power switching element, and then the potential detection circuit is used to detect the potential change of the current control element (equivalent to the potential corresponding to the level signal), wherein the potential change of the current control element is negatively correlated with the potential change of Vs, that is, when the Vs potential drops sharply, the current flowing through the current control circuit decreases, and the potential of the current control element needs to be increased and the resistance of the current control element needs to be reduced to increase the current to maintain the current in the current path constant, in this way, the potential change of Vs can be detected according to the potential of the current control element.

[0072] It should be noted that, in this embodiment, the constant current characteristic of the constant current source structure is utilized. When the Vs potential changes (this embodiment mainly considers the situation where the Vs potential changes sharply, and the above content has been cited), the potential of the current control element will also change accordingly. By detecting the potential of the current control element, the Vs potential can be quickly detected. When the detection circuit is integrated in the high-side driver chip, there is no need to increase other hardware costs (the IPM itself requires a power supply circuit). Of course, in other embodiments, in addition to using the above-mentioned constant current source circuit structure to detect the Vs potential, other detection circuits can also be used to detect the Vs potential. For example, a potential detector circuit can be used to directly detect the Vs potential.

[0073] In an optional implementation of an embodiment, the current control circuit 312 uses a voltage divider circuit to achieve current control. Specifically, Figure 6As shown, the current control circuit 312 also includes a first resistor R1 and a second resistor R2, and the current control element 3121 is a second MOS (switch) tube M1; the constant voltage source circuit 311 includes a first constant voltage source V2; wherein, the first resistor R1, one end of which is connected to the wire between the first power switch element 320 and the second power switch element 350, and the other end of which is connected to the drain of the second MOS tube, so that the second MOS tube M1 is connected to the wire between the first power element 330 and the second power element 350 through the resistor R1; the second resistor R2, one end of which is connected to the source of the second MOS tube M1, and the other end of which is connected to the ground terminal; the operational amplifier U2 (i.e., the operational amplifier 3122), the first input end of which is connected to the wire between the source of the second MOS tube M1 and the second resistor R2; the second input end of which is connected to the first constant voltage source V2; the output end of which is connected to the wire between the gate of the second MOS tube M1 and the potential detection circuit 313;

[0074] When the gate of the second MOS tube M1 receives the level signal output by the operational amplifier U2 , the potential of the gate of the second MOS tube M1 is increased to control conduction or decreased to control shutdown, so as to adjust to the resistance value.

[0075] In this embodiment, R1 (such as 5kΩ), M1 and R2 (such as 22Ω) form a voltage divider circuit, and by controlling the on / off of the MOS tube, the current of the R1, M1 loop and R2 is always the same. Figure 6 As shown in Figure 1, when the potential of Vs is high enough (normal state), the operational amplifier U2 reduces the gate potential of M1, so that the constant current determined by R2 and V2 is Flows in the path. Obviously, the current flowing here is also limited by R1. Therefore, when the Vs potential drops (abnormal conditions such as load short circuit) and the current limited by R1 is less than the constant current determined by R2 and V2, the operational amplifier U2 controls the rising potential (that is, the gate potential of M1) to make M1 fully ON (that is, turn on M1) to reduce the resistance of M1, thereby ensuring the constant current in the entire current path.

[0076] In an optional implementation of an embodiment, the potential detection circuit 313 includes a third resistor R3 and a fourth resistor R4; one end of the third resistor R3 is connected to the gate of the MOS tube M1, and the other end is connected to the fourth resistor R4; the output end of the operational amplifier U2 is specifically connected to the wire between the gate of the second MOS tube M1 and the third resistor R3; the high-side driver chip is specifically connected to the wire between the third resistor and the fourth resistor, so that the detection circuit is connected to the high-side driver chip ( Figure 6Not shown, where the SEN signal output terminal is the high-side driver chip); wherein the potential change (V R4 ) corresponds to a potential change Vg of the gate, and the potential change Vg of the gate is used to determine a potential change Vs of the second end.

[0077] In this embodiment, the potential detection circuit 313 can use a voltage divider circuit with M1 (gate) to detect the potential of M1. Specifically, the potential detection circuit 313 includes R3 (such as 300Ω) and R4 (such as 200Ω) connected in series with M1 (gate), and the potential point Vg of M1 (gate) and the potential point V R4 Voltage division, using the potential of R4, according to the principle of voltage division circuit, the current at Vg point is proportional to V R4 The current at the point is equal, that is, Vg / (R3+R4)=V R4 / R4, by detecting V R4 The voltage change at point Vg can be obtained by measuring the voltage change at point Vg.

[0078] In other embodiments, the potential detection circuit may adopt other potential detection structures besides the above circuit structure, which will not be described in detail here.

[0079] In an optional implementation of an embodiment, the potential detection circuit 313 also includes an inverter A1; the inverter A1, whose input end is connected to the wire between the third resistor R3 and the fourth resistor R4, and whose output end is connected to the high-side driver chip, so that the high-side driver chip is connected to the wire between the third resistor R3 and the fourth resistor R4 through the inverter, and the inverter A1 is used to invert the potential change Vg of the gate to obtain the first cut-off signal, and output the first cut-off signal to the high-side driver chip. Specifically, the inverted potential change (the output signal of the detection circuit 313, SEN) corresponds to the Vs potential change, and the SEN signal is output to the high-side driver chip to perform current protection on the high-side power element.

[0080] It can be understood that, as mentioned in the above embodiment, when the Vs potential drops sharply, the gate potential of M1 (i.e., Vg) needs to be raised through the operational amplifier output of a high level. In other words, when the Vs potential is at a low level, the Vg potential is at a high level, and the two are negatively correlated. The Vg potential is negatively correlated with V R4 The partial pressure is positively correlated with the partial pressure. Therefore, the V R4 or its corresponding Vg potential is opposite to the Vs potential that needs to be detected in the end. In order to further improve the output efficiency of the cut-off signal, the present embodiment adds an inverter A1. ByR4 The potential is inverted to obtain V SEN After output, it can be directly used as the cut-off signal output corresponding to the Vs potential.

[0081] In other embodiments, it is also possible not to set an inverter, by R4 The potential is processed in other ways and then output as a cut-off signal.

[0082] Furthermore, it may also include: a capacitor C1, one end of which is connected to the wire connecting the high-side driver chip and the third resistor and the second resistor, and the other end of which is connected to the ground terminal, for filtering the detected potential change of the fourth resistor.

[0083] In this embodiment, the capacitance of capacitor C1 may be 100p or other values. C1 serves as a filter capacitor and can remove or amplify the signal through filtering, so that the output signal is more accurate.

[0084] Furthermore, the constant voltage source circuit 311 also includes a second constant voltage source V1; the operational amplifier U2, whose third input terminal is connected to the second constant voltage source V1, and whose fourth input terminal is connected to the ground terminal, so that its output terminal outputs the level signal corresponding to the second constant voltage source or the ground terminal to the current control element.

[0085] Combination Figure 6 As shown, the operational amplifier U2 includes four input terminals, including two signal input terminals (positive phase input terminal and negative phase input terminal), and two power input terminals (positive power input terminal and negative power input terminal), wherein the positive phase input terminal (i.e., the second input terminal) and the negative phase input terminal (i.e., the first input terminal) are respectively connected to the branches of M1 and R2, and the first constant voltage source V2. By comparing the voltage between R2 and the first constant voltage source, when the voltage at point R2 drops to less than V2 (for example, V2 is a constant voltage source of 0.5V, and the R2 voltage is less than 0.5V), the second constant voltage source V1 (e.g., 12V) connected to the positive power input terminal is used to output a high level of 12V at the output terminal, so that the gate potential of M1 rises, thereby making the current in the current path constant. In the example Figure 6 In the example, a third constant voltage source V3 is further provided, one end of the third constant voltage source V3 is connected to Vs, and the other end is grounded.

[0086] For the above circuit structure, in order to prove the effectiveness of the scheme, the researchers of this application have obtained through experiments that: due to the abnormal load short circuit, the Vs potential drops, the Vs potential is detected and the cut-off signal (V SEN ) has a delay time of less than 0.1 μs. It can be understood that Vo in the figure is the drain potential of M1, which is positively correlated with the Vs potential.

[0087] In other embodiments, the above circuit structure can also be used to perform undercurrent protection on the power switch element, which is similar to the above principle and will not be described in detail here.

[0088] In some embodiments, the detection circuit can also be integrated into the high-side driver chip to meet the development cost and packaging miniaturization requirements of the driver chip. When the detection circuit 310 is integrated in the high-side driver chip, in one possible implementation, one end of the detection circuit 310 is connected to the power supply end of the high-side driver chip, and the other end is connected to the wire between the first power switch element 330 and the second power switch element 350. After detecting the change in the Vs potential, the first cut-off signal is output to the power supply end, and the current protection of the high-side power element is achieved by cutting off the power supply of the high-side driver chip; in another possible implementation, one end of the detection circuit 310 is connected to the high-side driver of the high-side driver chip, and the other end is connected to the wire between the first power switch element 330 and the second power switch element 350. The high-side driver turns off the first power switch element when receiving the first cut-off signal.

[0089] In other embodiments, it can be further combined Figure 4 Corresponding to the content of the embodiment, compared with the direct output of the first cut-off signal for current protection in the above embodiment, a protection logic module can also be integrated in the high-side driver chip. By connecting the protection logic module with the detection circuit, the detection circuit transmits the detected Vs potential change to the protection logic, and uses the protection logic to control the stop and resumption of operation of the high-side power switch element. Figure 7 and Figure 8 As shown, Figure 7 It is a structural diagram of the high-side driver chip in the related technology. The high-side driver chip includes power input (Vcc, through the low side), resistor (IntReg), signal input (HIN), input circuit (Input cir), filter circuit (DT&LPF), protection logic (Protectlogic), high level shift logic (High Level Shift Logic), high level shift (High Side LevelShift), high side gate drive (High Side Gate Drive), high side floating power input (Vb), high side gate output (Ho), high side floating power return (Vs, i.e. IGBT emitter voltage). Compared with Figure 7 In the example, Figure 8In the circuit structure, a detection circuit 310 (Vs Sense Cir) is added to detect the Vs potential change. The protection logic uses the detected Vs potential change as a Vsen signal, combines it with the HIN signal as a drive signal, and the IGBT is connected to the high-side gate drive (i.e., the high-side driver). After detection, the high-side driver drives the IGBT to send a cut-off signal to turn off the IGBT and stop the operation of the IGBT to provide protection. In this embodiment, by adding protection logic (Protect Logic, which is convenient for power-on recovery control of the gate drive chip), the detected Vs potential change is output to the protection logic to control the stop and recovery of the IGBT. Fig. 9 : is a flow chart of a current protection method of an IPM provided by an embodiment of the present application, wherein the IPM includes a detection circuit, a high-side driver chip and a first power switch element, a low-side driver chip and a second power switch element; the first end and the second end of the first power switch element constitute a first main current path from the first end to the second end, the third end of the first power switch element is used to control the switch of the first main current path, the fourth end and the fifth end of the second power switch element constitute a second main current path from the fourth end to the fifth end, and the sixth end of the second power switch element is used to control the switch of the second main current path; wherein the second end is electrically connected to the fourth end, so that the first power switch element and the second power switch element are connected in series; as Fig. 9 As shown, the method provided in this embodiment may include the following steps S901 and S902.

[0090] Step S901: The high-side driver chip transmits a first drive signal to the third terminal of the first power element to drive the first power switch element to be turned on or off based on the first drive signal;

[0091] Step S902: The low-side driver chip transmits a second drive signal to the sixth terminal of the second power element, so as to drive the second power switch element to be turned on or off based on the second drive signal;

[0092] Step S903, the detection circuit detects the potential change of the second end of the first power switch element, and transmits a first cut-off signal to the high-side driver chip according to the potential change of the second end, wherein the first cut-off signal is used to cut off the first power switch element, so that the first power switch element is placed in a current protection state.

[0093] Through the above scheme, the detection circuit is used to detect the potential change of the second end (output end) of the high-side power switch element (i.e., V SThe high-side power switch element is placed in a current protection state by detecting the potential change of the output terminal of the high-side power switch element and identifying the abnormal state of the power switch element, without combining the low-side protection circuit and the protection signal of the microcontroller.

[0094] It should be noted here that the above method provided in the embodiment of the present application is similar to the implementation method and principle of the above circuit structure embodiment, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the structural embodiment will not be described in detail here.

[0095] The embodiment of the present application also provides a computer-readable storage medium, on which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, the overcurrent protection method of the IPM is implemented.

[0096] It should be noted here that the above-mentioned medium provided in the embodiment of the present application is similar to the implementation method and principle of the above-mentioned circuit structure embodiment, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the structural embodiment will not be described in detail here.

[0097] Fig.10 An IPM control system provided in an embodiment of the present application, such as Fig.10 As shown, the IPM control system 1000 includes the IPM 300 and a load device 400, wherein the load device 400 is electrically connected to the first power switch element. When the power switch element is turned on or off, the load device runs or stops. When the load device is in an abnormal state such as a short circuit, the power switch element is protected by current control by adopting the above technical solution to avoid damage to the power switch element.

[0098] It should be noted here that the above-mentioned system provided in the embodiment of the present application is similar to the implementation method and principle of the above-mentioned circuit structure embodiment, and can achieve the same technical effect. The parts and beneficial effects of this embodiment that are the same as the structural embodiment will not be described in detail here.

[0099] The present application also provides a computer-readable storage medium, which may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a disk or an optical disk, and other media that can store program codes. Specifically, the computer-readable storage medium stores program instructions, and the program instructions are used for the methods in the above embodiments.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0101] For the convenience of explanation, the above description has been made in conjunction with specific embodiments. However, the above exemplary discussion is not intended to be exhaustive or limit the embodiments to the specific forms disclosed above. Based on the above teachings, various modifications and variations can be obtained. The selection and description of the above embodiments are to better explain the principles and practical applications, so that those skilled in the art can better use the embodiments and various different variations of the embodiments suitable for specific use considerations.

Claims

1. An intelligent power module IPM, characterized in that: It includes a detection circuit, a high-side driving chip and a first power switch element, a low-side driving chip and a second power switch element; the first end and the second end of the first power switch element constitute a first main current path from the first end to the second end, the third end of the first power switch element is used to control the switch of the first main current path, the fourth end and the fifth end of the second power switch element constitute a second main current path from the fourth end to the fifth end, and the sixth end of the second power switch element is used to control the switch of the second main current path; wherein the second end is electrically connected to the fourth end, so that the first power switch element and the second power switch element are connected in series; The high-side driver chip is electrically connected to the third end of the first power switch element, and is used to transmit a first drive signal to the first power switch element, wherein the first drive signal is used to control the current flow in the first main current path and drive the first power switch element to be turned on or off; The low-side driver chip is electrically connected to the sixth end of the second power switch element, and is used to transmit a second drive signal to the second power switch element, wherein the second drive signal is used to control the current flow in the second main current path and drive the second power switch element to be turned on or off; The detection circuit has one end connected to the high-side driver chip and the other end connected to the wire between the first power switch element and the second power switch element, and is used to detect the potential change of the second end of the first power switch element, and transmit a first cut-off signal to the high-side driver chip according to the potential change of the second end, wherein the first cut-off signal is used to cut off the first power switch element, so that the first power switch element is placed in a current protection state; The detection circuit includes a constant voltage source circuit, a current control circuit and a potential detection circuit; wherein the current control circuit includes a current control element and an operational amplifier electrically connected to the current control element; The current control circuit has one end connected to the wire between the first power element and the second power element through the current control element, and the other end connected to the constant voltage source circuit through the operational amplifier; the potential detection circuit has one end connected to the current control element, and the other end connected to the high-side drive chip; When the potential of the second end of the first power switching element changes, the operational amplifier outputs a corresponding level signal to the current control element based on the constant voltage source circuit to adjust the resistance of the current control element and provide a constant current for the current path; the potential detection circuit detects the potential change of the current control element after adjusting the resistance, and detects the potential change of the second end according to the potential change.

2. The IPM according to claim 1, characterized in that: The first power switch element and the second power switch element respectively include at least one of the following: an insulated gate bipolar transistor IGBT tube, a first metal oxide semiconductor field effect transistor MOS tube, and a bipolar transistor BJT tube.

3. The IPM according to claim 2, characterized in that: The first power switch element and / or the second power switch element is an IGBT tube, the first end and / or the fourth end is the collector of the IGBT tube, the second end and / or the fifth end is the emitter of the IGBT tube, and the third end and / or the sixth end is the gate of the IGBT tube; or, The first power switch element and / or the second power switch element is a first MOS tube, the first end and / or the fourth end are respectively the drain of the first MOS tube, the second end and / or the fifth end are the source of the first MOS tube, and the third end and / or the sixth end are the gate of the first MOS tube; or, The first power switch element and / or the second power switch element is a BJT tube, the first end and / or the fourth end are respectively the collectors of the BJT tube, the second end and / or the fifth end are respectively the emitters of the BJT tube, and the third end and / or the sixth end are respectively the bases of the BJT tube.

4. The IPM according to any one of claims 1 to 3, characterized in that: It also includes a third power switch element and a fourth power switch element, wherein the seventh end and the eighth end of the third power switch element constitute a third main current path from the seventh end to the eighth end, the ninth end of the third power switch element is used to control the switch of the third main current path, the tenth end and the eleventh end of the fourth power switch element constitute a fourth main current path from the tenth end to the eleventh end, and the twelfth end of the fourth power switch element is used to control the switch of the fourth main current path; wherein the eighth end is electrically connected to the tenth end to form a second connection structure of the third power switch element and the fourth power switch element; The high-side driver chip is also electrically connected to the ninth terminal of the third power switch element, and is used to transmit a third drive signal to the third power switch element, wherein the third drive signal is used to control the current flow in the third main current path and drive the third power switch element to be turned on or off; The low-side driver chip is also electrically connected to the twelfth terminal of the fourth power switch element, and is used to transmit a fourth drive signal to the fourth power switch element, wherein the fourth drive signal is used to control the current flow in the fourth main current path and drive the fourth power switch element to be turned on or off; The detection circuit has one end connected to the high-side driver chip and the other end connected to the wire between the third power switch element and the fourth power switch element, and is used to detect the potential change of the ninth end of the third power switch element and transmit a second cut-off signal to the high-side driver chip according to the potential change, wherein the second cut-off signal is used to cut off the third power switch element, so that the third power switch element is placed in a current protection state.

5. The IPM according to claim 4, characterized in that: The device further comprises a fifth power switch element and a sixth power switch element, wherein the thirteenth terminal and the fourteenth terminal of the fifth power switch element constitute a fifth main current path from the thirteenth terminal to the fourteenth terminal, the fifteenth terminal of the fifth power switch element is used to control the switch of the fifth main current path, the sixteenth terminal and the seventeenth terminal of the sixth power switch element constitute a sixth main current path from the sixteenth terminal to the seventeenth terminal, and the eighteenth terminal of the sixth power switch element is used to control the switch of the sixth main current path; wherein the fourteenth terminal is electrically connected to the sixteenth terminal to form a third connection structure of the fifth power switch element and the sixth power switch element; The high-side driver chip is also electrically connected to the fifteenth terminal of the fifth power switch element, and is used to transmit a fifth drive signal to the fifth power switch element, wherein the fifth drive signal is used to control the current flow in the fifth main current path and drive the fifth power switch element to be turned on or off; The low-side driver chip is also electrically connected to the eighteenth terminal of the sixth power switch element, and is used to transmit a sixth drive signal to the sixth power switch element, wherein the sixth drive signal is used to control the current flow in the sixth main current path and drive the sixth power switch element to be turned on or off; The detection circuit has one end connected to the high-side driver chip and the other end connected to the wire between the fifth power switch element and the sixth power switch element, and is used to detect the potential change of the fourteenth end of the fifth power switch element, and transmit a third cut-off signal to the high-side driver chip according to the potential change, and the third cut-off signal is used to cut off the fifth power switch element, so that the fifth power switch element is placed in a current protection state.

6. The IPM according to any one of claims 1 to 3, characterized in that: The detection circuit is integrated inside the high-side driver chip; The detection circuit has one end specifically connected to the high-side driving module of the high-side driving chip, and the other end specifically connected to the high-side floating power return terminal of the high-side driving chip, so that the detection circuit is connected to the wire connected between the first power switch element and the second power switch element through the high-side floating power return terminal to detect the potential change of the second end of the first power switch element, and transmit the first cut-off signal to the high-side driving module according to the potential change of the second end; The high-side driving module has one end connected to the detection circuit and the other end connected to the first power switching element, and is used to drive the first power switching element to be turned on or off according to the first driving signal when the first cut-off signal is not received; or, when the first cut-off signal is received, cut off the first power switching element according to the first cut-off signal, so that the first power switching element is placed in a current protection state.

7. The IPM according to claim 1, characterized in that: The constant voltage source circuit includes a first constant voltage source; the current control circuit also includes a first resistor and a second resistor, and the current control element is a second MOS tube; The first resistor has one end connected to the wire between the first power switch element and the second power switch element, and the other end connected to the drain of the second MOS tube; The second resistor has one end connected to the source of the second MOS tube and the other end connected to the ground; The operational amplifier has a first input terminal connected to a wire between the source of the second MOS tube and the second resistor; Its second input terminal is connected to the first constant voltage source; Its output end is connected to the wire between the gate of the second MOS tube and the potential detection circuit; When the gate of the second MOS tube receives the level signal output by the operational amplifier, the potential of the gate of the second MOS tube rises or drops to be adjusted to the resistance value.

8. The IPM according to claim 7, characterized in that: The potential detection circuit includes a third resistor and a fourth resistor; one end of the third resistor is connected to the gate of the second MOS tube, and the other end is connected to the fourth resistor; the output end of the operational amplifier is specifically connected to the wire between the gate of the second MOS tube and the third resistor; the high-side drive chip is specifically connected to the wire between the third resistor and the fourth resistor, so that the detection circuit is connected to the high-side drive chip; The potential change of the connection point where the high-side driver chip is connected to the wire between the third resistor and the fourth resistor corresponds to the potential change of the gate, and the potential change of the gate is used to determine the potential change of the second end.

9. The IPM according to claim 8, characterized in that: The potential detection circuit also includes an inverter; The inverter has an input end connected to the wire between the third resistor and the fourth resistor, and an output end connected to the high-side driver chip, so that the high-side driver chip is connected to the wire between the third resistor and the fourth resistor through the inverter. The inverter is used to invert the potential change of the gate to obtain the first cut-off signal, and output the first cut-off signal to the high-side driver chip.

10. The IPM according to claim 1, characterized in that: The constant voltage source circuit further includes a second constant voltage source; The operational amplifier has its third input terminal connected to the second constant voltage source and its fourth input terminal connected to the ground terminal, so that its output terminal outputs the level signal corresponding to the second constant voltage source or the ground terminal to the current control element.

11. A current protection method for IPM, characterized in that: The IPM includes a detection circuit, a high-side driving chip and a first power switch element, a low-side driving chip and a second power switch element; the first end and the second end of the first power switch element constitute a first main current path from the first end to the second end, the third end of the first power switch element is used to control the switch of the first main current path, the fourth end and the fifth end of the second power switch element constitute a second main current path from the fourth end to the fifth end, and the sixth end of the second power switch element is used to control the switch of the second main current path; wherein the second end is electrically connected to the fourth end, so that the first power switch element and the second power switch element are connected in series, and the method includes: The high-side driver chip transmits a first drive signal to the third terminal of the first power element to drive the first power switch element to be turned on or off based on the first drive signal; The low-side driver chip transmits a second drive signal to the sixth terminal of the second power element to drive the second power switch element to be turned on or off based on the second drive signal; The detection circuit detects a potential change of the second end of the first power switch element, and transmits a first cut-off signal to the high-side driver chip according to the potential change of the second end, wherein the first cut-off signal is used to cut off the first power switch element, so that the first power switch element is placed in a current protection state; The detection circuit includes a constant voltage source circuit, a current control circuit and a potential detection circuit; wherein the current control circuit includes a current control element and an operational amplifier electrically connected to the current control element; The current control circuit has one end connected to the wire between the first power element and the second power element through the current control element, and the other end connected to the constant voltage source circuit through the operational amplifier; the potential detection circuit has one end connected to the current control element, and the other end connected to the high-side drive chip; When the potential of the second end of the first power switching element changes, the operational amplifier outputs a corresponding level signal to the current control element based on the constant voltage source circuit to adjust the resistance of the current control element and provide a constant current for the current path; the potential detection circuit detects the potential change of the current control element after adjusting the resistance, and detects the potential change of the second end according to the potential change.

12. An IPM control system, characterized in that: It comprises the IPM as claimed in any one of claims 1 to 10 and a load device, wherein the load device is electrically connected to the first power switch element.

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