Overcurrent detection method and system of motor controller, vehicle, equipment and medium

Abstract

The invention discloses an overcurrent detection method and system of a motor controller, a vehicle, equipment and a medium. The over-current detection system of the motor controller comprises a plurality of over-current detection modules which are used for collecting conduction voltages of a collector electrode and an emitter electrode of each IGBT power switch tube, determining whether each IGBT power switch tube is in an over-current state according to the conduction voltages and a preset voltage over-current threshold value, and outputting a state signal indicating whether the IGBT power switch tube is in an over-current state, the voltage overcurrent threshold value is determined according to the output characteristics of the IGBT power switch tube; and the fault logic processing module is used for feeding back an over-current signal to the motor controller when the IGBT power switch tube with over-current is confirmed according to the state signals output by the plurality of over-current detection modules, so that the motor controller adopts over-current protection measures on the IGBT power switch tube. According to the invention, the current utilization rate of the IGBT can be improved, the risk of damage caused by turn-off of the IGBT under the condition of large current can be reduced, and the use safety of the IGBT is improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicles, and particularly to an overcurrent detection method, system, vehicle, device and medium for a motor controller. Background Art

[0002] Insulated Gate Bipolar Transistor (IGBT) is a power semiconductor device, which has the advantages of both the high input impedance of MOSFET and the low conduction voltage drop of GTR. With the development of the power electronics technology industry, as the core component of energy conversion and transmission, the application scope of IGBT devices is becoming wider and wider; especially the rapid development of the new energy electric vehicle industry has accelerated the promotion of the breadth and depth of IGBT device applications. As the core device for energy conversion, the monitoring of the working state and the protection of abnormal states of IGBT are particularly important during the application process of IGBT. The monitoring and protection of the collector current (Ic) of the IGBT module are the core technologies of IGBT module application. The high utilization rate of the collector current (Ic) of the IGBT module is beneficial to improving the overall output efficiency of the IGBT module, increasing the power density of the entire controller, and ultimately directly affecting the output of the vehicle's dynamic performance. Larger currents will also lead to an increase in module losses and the probability of IGBT module damage. The protection of large currents in IGBT modules is extremely critical in IGBT application technologies.

[0003] Currently, the existing overcurrent detection and protection methods for IGBT modules are basically divided into two categories. One is an overcurrent protection method based on the detection of phase current by a Hall current sensor, and the other is an overcurrent protection method using a highly integrated drive chip based on the desaturation characteristic of the IGBT itself.

[0004] The overcurrent protection method using a highly integrated drive chip based on the desaturation characteristic of the IGBT itself has the following defects: 1. The desaturation voltage detection threshold of the integrated chip is a fixed threshold and cannot be adjusted, resulting in poor flexibility in setting the protection point; 2. The desaturation voltage detection threshold of the integrated chip is relatively large, generally about 8V, and when the protection is triggered, the collector current is 5 to 8 times the rated current, and the fault trigger current is large, increasing the probability of explosion and damage of the IGBT during the protection process; 3. The finished product of the integrated drive chip with desaturation detection function is relatively high, and coupled with the relatively large single-machine usage in the system, it will increase the design cost of the IGBT system protection scheme.

[0005] The overcurrent protection method based on the detection of phase current by a Hall current sensor has the following defects: The Hall current sensor current detection method has a relatively large detection system delay, resulting in poor timeliness of fault protection; the Hall current sensor current detection method is only used for type II short-circuit protection and cannot achieve timely protection for type I short-circuit faults. Summary of the Invention

[0006] Based on this, it is necessary to provide an overcurrent detection method, system, vehicle, device and medium for a motor controller to solve the above technical problems, which can improve the current utilization rate of IGBTs, reduce the risk of damage to IGBTs when turning off under high current conditions, and improve the safety of IGBT use.

[0007] In a first aspect, an overcurrent detection system for a motor controller is provided. The motor controller includes an inverter circuit, and the inverter circuit includes a plurality of IGBT power switching tubes. The overcurrent detection system includes:

[0008] A plurality of overcurrent detection modules, which are connected to the plurality of IGBT power switching tubes one by one, are used to collect the conduction voltage between the collector and the emitter of each IGBT power switching tube, and determine whether each IGBT power switching tube is overcurrent according to the conduction voltage and a preset voltage overcurrent threshold, and output a status signal indicating whether it is overcurrent. Among them, the voltage overcurrent threshold is determined according to the output characteristics of the IGBT power switching tube;

[0009] A fault logic processing module, which is connected to the plurality of overcurrent detection modules, is used to feedback an overcurrent signal to the motor controller when it is confirmed that there is an overcurrent IGBT power switching tube according to the status signals output by the plurality of overcurrent detection modules, so that the motor controller can adopt overcurrent protection measures for the IGBT power switching tube.

[0010] In some examples, the overcurrent detection module includes:

[0011] A detection unit for the conduction voltage between the collector and the emitter of the IGBT power switching tube, and the detection unit includes an operational amplifier, a conditioning resistor and an isolation diode;

[0012] A comparator, which is used to compare the conduction voltage between the collector and the emitter of the IGBT power switching tube output by the detection unit with the voltage overcurrent threshold, and output a status signal indicating whether the IGBT power switching tube is overcurrent;

[0013] A voltage overcurrent threshold setting module, which is used to divide the voltage of the input power supply of the IGBT to obtain the voltage overcurrent threshold. Among them, the magnitude of the voltage division can be changed by adjusting the resistance value of the voltage overcurrent threshold setting module.

[0014] In some examples, the voltage overcurrent threshold setting module includes an adjustable resistor.

[0015] In some examples, the overcurrent detection module further includes:

[0016] A digital isolation module is used to isolate and transmit the status signal indicating whether the IGBT power switch is overcurrent to the fault logic processing module.

[0017] In some examples, the digital isolation module includes an integrated digital isolation chip or a discrete opto - electrical coupling chip.

[0018] In some examples, the fault logic processing module is specifically configured to:

[0019] When at least one of the status signals output by multiple over - current detection modules indicates that the IGBT power switch has an over - current fault, feedback an over - current signal to the motor controller so that the motor controller takes over - current protection measures for the IGBT power switch.

[0020] In a second aspect, a vehicle is provided, including: the over - current detection system of the motor controller according to the first aspect described above.

[0021] In a third aspect, an over - current detection method for a motor controller is provided. The motor controller includes an inverter circuit, and the inverter circuit includes multiple IGBT power switches. The over - current detection includes:

[0022] Collect the conduction voltage between the collector and the emitter of each IGBT power switch;

[0023] Determine whether each IGBT power switch is overcurrent according to the conduction voltage and a preset voltage over - current threshold, and output a status signal indicating whether it is overcurrent, where the voltage over - current threshold is determined according to the output characteristics of the IGBT power switch;

[0024] When confirming the IGBT power switch with over - current according to the status signal indicating whether each IGBT power switch is overcurrent, feedback an over - current signal to the motor controller so that the motor controller takes over - current protection measures for the IGBT power switch.

[0025] In a fourth aspect, a computer device is provided, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps of the over - current detection method for the motor controller in the third aspect described above are implemented.

[0026] In a fifth aspect, a computer - readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the steps of the over - current detection method for the motor controller in the third aspect described above are implemented.

[0027] In a sixth aspect, a computer program product is provided, on which a computer program is stored. When the program is executed by a processor, the steps of the overcurrent detection method of the motor controller in the above-mentioned first aspect and any possible implementation manner of the first aspect are implemented.

[0028] By adopting the embodiments of the present application, it is possible to improve the current utilization rate of the IGBT, reduce the risk of damage to the IGBT when turning off under large current conditions, and improve the safety of using the IGBT. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objectives, and advantages of the present application will become more obvious:

[0030] Figure 1 It is a structural block diagram of the overcurrent detection system of the motor controller provided by the embodiment of the present application;

[0031] Figure 2 It is a schematic diagram of the overcurrent detection system of the motor controller provided by the embodiment of the present application;

[0032] Figure 3 It is a circuit schematic diagram of the overcurrent detection system of the motor controller provided by the embodiment of the present application;

[0033] Figure 4 It is a schematic diagram of the output characteristic curve of an IGBT power switch tube;

[0034] Figure 5 It is a flowchart of the overcurrent detection method of the motor controller provided by the embodiment of the present application;

[0035] Figure 6 It is a structural block diagram of the computer device provided by the embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] The present application will be further described in detail below in conjunction with the embodiments and the drawings. It can be understood that the specific embodiments described herein are only used to explain the related application, rather than limiting the application. In addition, it should be noted that only the parts related to the application are shown in the drawings for the convenience of description.

[0037] It should be noted that, without conflict, the embodiments and the features of the embodiments in the present application can be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0038] The overcurrent detection method, system, vehicle, device, and medium of the motor controller according to the embodiments of the present application will be described in detail below with reference to the drawings.

[0039] First, the motor controller of the vehicle is described. The motor controller is one of the core components of an electric vehicle and is responsible for converting the direct current of the power battery into alternating current to drive the motor. The motor controller includes an inverter, and the inverter usually includes multiple power switch tubes, also known as power devices. The power devices are generally IGBTs or SiC MOSFETs. Taking the IGBT power switch tube as an example, the on-off control realizes the operation of the inverter.

[0040] Figure 1 is a block diagram of an overcurrent detection system for a motor controller according to an embodiment of the present application. As Figure 1 shown, the overcurrent detection system for a motor controller according to an embodiment of the present application includes: an overcurrent detection module 110 and a fault logic processing module 120, where:

[0041] There are multiple overcurrent detection modules 110. The multiple overcurrent detection modules 110 are connected to the multiple IGBT power switch tubes one by one, and are used to collect the conduction voltage between the collector and emitter of each IGBT power switch tube, and determine whether each IGBT power switch tube is overcurrent according to the conduction voltage and a preset voltage overcurrent threshold, and output a status signal indicating whether it is overcurrent. The voltage overcurrent threshold is determined according to the output characteristics of the IGBT power switch tube. The fault logic processing module 120 is connected to the multiple overcurrent detection modules 110, and is used to feedback an overcurrent signal to the motor controller when it is confirmed that there is an overcurrent IGBT power switch tube according to the status signals output by the multiple overcurrent detection modules, so that the motor controller can adopt overcurrent protection measures for the IGBT power switch tube.

[0042] Among them, the fault logic processing module is specifically used for: when at least one of the status signals output by the multiple overcurrent detection modules indicates that the IGBT power switch tube has an overcurrent fault, feedback an overcurrent signal to the motor controller, so that the motor controller can adopt overcurrent protection measures for the IGBT power switch tube.

[0043] As a specific example, the overcurrent detection module 110 includes: a detection unit for the conduction voltage between the collector and emitter of the IGBT power switch tube. The detection unit includes an operational amplifier, a conditioning resistor, and an isolation diode; a comparator for comparing the conduction voltage between the collector and emitter of the IGBT power switch tube output by the detection unit with the overcurrent threshold voltage and outputting a status signal indicating whether the IGBT power switch tube is overcurrent; an overcurrent threshold voltage setting module for conditioning and dividing the power supply to obtain the overcurrent threshold voltage. The magnitude of the threshold voltage can be changed by adjusting the resistance value of the overcurrent threshold voltage setting module. In this example, the overcurrent threshold voltage setting module includes an adjustable resistor.

[0044] In one embodiment of the present application, the overcurrent detection module further includes: a digital isolation module for isolating and transmitting a status signal of whether the IGBT power switch tube is overcurrent to the fault logic processing module. Further, the digital isolation module includes an integrated digital isolation chip or a separate optical-electrical coupling chip.

[0045] The overcurrent detection system of the motor controller of the embodiment of the present application is used in specific applications, such as Figure 2 As shown, the overcurrent detection system of the motor controller is integrated with the motor controller, the IGBT collector-emitter conduction voltage Vce is collected through the overcurrent detection module, the overcurrent protection threshold is set and the fault status of the IGBT is output through the digital isolation chip; the fault logic processing module performs logic processing on the received IGBT fault status signal and summarizes it into a total fault signal, which is connected to the control unit on the one hand to realize fault reporting and fault warning; on the other hand, it is connected to the drive signal logic unit to realize timely processing of the fault signal, so that the inverter enters the wave-sealing mode or the ASC mode after the fault occurs, which has the effect of rapid protection.

[0046] Combination Figure 2 As shown, the inverter consists of six IGBTs, Q1, Q3, Q5, Q4, Q2 and Q6, forming a three-phase full-bridge inverter circuit to achieve conversion from DC voltage to AC voltage, wherein Q1 and Q4 form a U-phase half-bridge circuit, Q3 and Q2 form a V-phase half-bridge circuit, Q5 and Q6 form a W-phase half-bridge circuit, and U / V / W are respectively connected to the three-phase input of the AC motor.

[0047] The overcurrent detection module realizes the detection of IGBT conduction voltage drop, setting of overcurrent threshold and digital signal isolation transmission. Taking the U-phase upper bridge IGBTQ1 as an example for analysis, its circuit schematic diagram is as follows Figure 3 As shown. The IGBT on-state voltage drop detection is composed of an operational amplifier, an external conditioning resistor, and an isolation diode. According to the "virtual short" and "virtual disconnection" principles of the operational amplifier, by adjusting the resistance values of the external resistors R1, R3, and R4, the output voltage value of the 6th pin of the operational amplifier U1 can be theoretically equal to the voltage (Vce) between the collector and emitter of the IGBTQ1 when it is turned on; the voltage regulator D2 makes the voltage of the 3rd pin of the operational amplifier U1 not exceed the device use requirements of the operational amplifier, to prevent damage to the operational amplifier U1 when the voltage across the Vce of the Q1 turn-off device is the bus voltage.

[0048] The overcurrent threshold setting can set a specific protection threshold Vref according to project requirements. Combining the working characteristics of the voltage comparator, it realizes the conversion from analog signal to digital signal, and then uses the high and low levels of the digital signal to identify the working state of the IGBT. When the output voltage of the 6th pin of the operational amplifier U1 is greater than the overcurrent threshold reference voltage Vref, the comparator U2 outputs a digital level of high level "1", indicating that the IGBT Q1 has an overcurrent fault; when the output voltage of the 6th pin of the operational amplifier U1 is less than the overcurrent threshold reference voltage Vref, the comparator U2 outputs a digital level of low level "0", indicating that the working state of the IGBT Q1 is normal. The setting of the overcurrent protection threshold voltage is obtained by series voltage division of the power supply Vdriver_q1 through the resistors R5 and R6. The selection of the resistance values of the voltage division resistors R5 and R6 can be adjusted according to the different threshold voltages Vref to achieve the adjustability of the overcurrent protection threshold. The selection of the overcurrent threshold is based on the combination of the output characteristics of the IGBT used and the actual project application. The output peak current of a certain project is 25 Arms. Combining the voltage platform used, a module of 1200V / 50A is selected. According to the relevant project application experience, the protection current based on the on-state voltage drop of the IGBT module output characteristics is set to 75A. Referring to the IGBT drive voltage of 15V in the project drive circuit and combining the output characteristic curve of the IGBT, the protection threshold voltage Vref can be determined. The output characteristics of a certain model of IGBT module are as Figure 4 shown, and it can be seen from Figure 4 that when the current flowing through the IGBT is 75A, its on-state voltage drop Vce is 2.4V, that is, the selected overcurrent protection threshold voltage Vref is 2.4V.

[0049] The digital isolation module realizes the isolation transmission function of the overcurrent fault digital signal, usually by using an integrated digital isolation chip or a discrete opto - electrical coupling chip, etc. This application uses an integrated digital isolation chip with an enabling function to realize the isolation transmission of the digital signal. The signal input terminal of the integrated digital isolation chip is connected to the output signal of the 6th pin of comparator U2. The output digital signal of the integrated digital isolation chip is Ioc_q1. A high level "1" of the digital signal Ioc_q1 indicates an overcurrent fault, and a low level "0" of the digital signal Ioc_q1 indicates no overcurrent fault. The enabling signal of the integrated digital isolation chip comes from the control signal of the gate of IGBTQ1, which can realize the targeted detection of the IGBT collector - emitter voltage. When the gate voltage Vge_Q1 of Q1 is high, IGBTQ1 is turned on, the integrated digital isolation chip is enabled, and the transmission of the signal from the input terminal to the output terminal of the integrated digital isolation chip is realized; when the gate voltage Vge_Q1 of Q1 is low, IGBTQ1 is turned off, the integrated digital isolation chip is not enabled, the output of the integrated digital isolation chip does not follow the input signal, and a pull - down resistor is configured at the output terminal of the integrated isolation chip. The default output level of the output signal Ioc_q1 is low. Therefore, when the integrated isolation chip is not enabled, the Ioc_q1 signal is low level.

[0050] The fault logic processing module realizes the logic processing function for the overcurrent flag signals Ioc_q1, Ioc_q2, Ioc_q3, Ioc_q4, Ioc_q5, Ioc_q6 from 6 IGBTs. Its main logic function is "NOR". When any one of the overcurrent flag signals is high, the fault logic processing module outputs a low level.

[0051] The gate - level pre - drive module realizes the isolation control of the IGBT. The gate - level pre - drive module receives the control signal from the drive signal logic unit and generally uses opto - isolation or magnetic isolation to isolate and amplify the low - voltage drive signal to realize the control function of the low - voltage system for the high - voltage system.

[0052] The drive signal logic unit realizes the enhancement of the drive capabilities of the six - way drive signals adjusted by the control unit and the processing of the fault protection logic to realize the implementation of the hardware fault protection logic.

[0053] The control unit is mainly composed of a single - chip microcomputer and realizes functions such as the control of the inverter module, the execution of the fault detection and protection logic through software logic strategies.

[0054] The overcurrent detection system of the motor controller according to the embodiments of the present application can collect the collector-emitter voltage drop Vce of the IGBT through an external circuit and flexibly set the overcurrent protection threshold according to the actual situation of the project. Compared with the desaturation protection method of the integrated drive chip, the protection threshold can be set. And according to the actual situation of the project, a protection threshold lower than the desaturation threshold is set to adjust the current protection threshold of the IGBT module, and the setting flexibility is significantly improved; the collector-emitter voltage drop Vce of the IGBT can be collected through an external circuit, and the overcurrent protection threshold can be flexibly set according to the actual situation of the project; the protection current of the IGBT module can be set relatively low according to the actual application situation. The set protection current is several times smaller than the desaturation current of the IGBT module, which can enable the system to trigger the IGBT module protection mechanism under a lower fault current condition, reducing the risk of damage to the IGBT module due to large-current turn-off; compared with the overcurrent protection method of the integrated drive chip, the material cost of the present application is lower, which is more convenient for mass use in pump control schemes with greater cost pressure; the present application is based on the output characteristics of the IGBT, and combines the relationship between the output current Ic and the collector-emitter voltage Vce of the IGBT to achieve the triggering of overcurrent protection faults. Compared with the overcurrent protection means combined with the current detection and regulation circuit of the Hall current sensor, the fault protection delay is small, the action is fast, and the anti-interference ability is strong.

[0055] In addition, based on the output characteristics of the IGBT, the present application can implement the setting of the fault protection threshold in the case of a similar "desaturation" fault; based on the output characteristics of the IGBT, a suitable "desaturation" threshold can be configured according to the project requirements, reducing the current threshold of the IGBT overcurrent fault and reducing the risk of explosion and damage caused by large-current turn-off of the IGBT during overcurrent fault protection.

[0056] In one embodiment, a method is provided, including: according to the overcurrent detection system of the motor controller described in any one of the above embodiments, this method can flexibly design the magnitude of the current threshold for the "desaturation" protection of the system in combination with the actual application situation of the IGBT current, which can not only improve the current utilization rate of the IGBT, but also reduce the risk of damage to the IGBT during turn-off under large-current conditions, improving the safety of IGBT use.

[0057] In addition, the other constitutions and functions of the method according to the embodiments of the present application are known to those of ordinary skill in the art, and will not be elaborated here.

[0058] Figure 5 is a flowchart of the overcurrent detection method of the motor controller according to an embodiment of the present application. As Figure 5 shown, the overcurrent detection method of the motor controller according to the embodiments of the present application includes the following steps:

[0059] S501: Collect the conduction voltages between the collector and emitter of each IGBT power switch;

[0060] S502: Determine whether each IGBT power switch is overcurrent based on the conduction voltage and a preset overvoltage and overcurrent threshold, and output a status signal indicating whether there is overcurrent. The overvoltage and overcurrent threshold is determined according to the output characteristics of the IGBT power switch;

[0061] S503: Based on the status signals indicating whether each IGBT power switch is overcurrent, when an overcurrent IGBT power switch is identified, feedback an overcurrent signal to the motor controller so that the motor controller can take overcurrent protection measures for the IGBT power switch.

[0062] According to the overcurrent detection method of the motor controller in the embodiments of the present application, the collector-emitter voltage Vce of the IGBT is collected through an external circuit, and the overcurrent protection threshold is flexibly set according to the actual situation of the project. Compared with the desaturation protection method of the integrated drive chip, the protection threshold can be set. And according to the actual situation of the project, a protection threshold lower than the desaturation threshold is set to adjust the current protection threshold of the IGBT module, and the setting flexibility is significantly improved; the protection current of the IGBT module can be set relatively low according to the actual application situation. The set protection current is less than the desaturation current of the IGBT module, which can enable the system to trigger the IGBT module protection mechanism under low fault current conditions, reducing the risk of damage to the IGBT module due to large current turn-off; compared with the overcurrent protection method of the integrated drive chip, the material cost of the present application is lower, which is more convenient for mass use in pump control schemes with greater cost pressure; the present application is based on the output characteristics of the IGBT, and combines the relationship between the IGBT output current Ic and the collector-emitter voltage Vce to trigger overcurrent protection faults. Compared with the overcurrent protection means combining Hall current sensor current detection and adjustment circuits, the fault protection delay is small, the action is fast, and the anti-interference ability is strong.

[0063] In addition, based on the output characteristics of the IGBT, the present application can implement the setting of the fault protection threshold in case of a "desaturation" - like fault; based on the output characteristics of the IGBT, a suitable "desaturation" threshold can be configured according to project requirements, reducing the current threshold of the IGBT overcurrent fault and the risk of explosion and damage to the IGBT caused by large current turn-off during overcurrent fault protection.

[0064] For the specific limitations on the overcurrent detection method of the motor controller, reference can be made to the limitations on the overcurrent detection system of the motor controller in the foregoing text, which will not be elaborated here. Each module of the above-mentioned overcurrent detection system of the motor controller can be implemented in whole or in part by software, hardware, and their combination. The above-mentioned each module can be embedded in or independent of the processor in the computer device in the form of hardware, or stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above-mentioned each module.

[0065] In one embodiment, a computer device is provided. Figure 6 It is the structural block diagram of the computer device provided in the embodiment of the present application. Refer to Figure 6 . The computer device includes a memory and a processor. A computer program is stored in the memory. When the processor executes the computer program, it implements the foregoing embodiment of the overcurrent detection method of the motor controller. For example, execute: acquisition of overcurrent faults of IGBT power switching tubes;

[0066] Determine whether each IGBT power switching tube is overcurrent according to the conduction voltage and a preset overcurrent threshold voltage, and output a status signal indicating whether it is overcurrent, where the overcurrent threshold voltage is determined according to the output characteristics of the IGBT power switching tube;

[0067] According to the status signal indicating whether each IGBT power switching tube is overcurrent, when it is confirmed that there is an overcurrent IGBT power switching tube, feedback an overcurrent signal to the motor controller so that the motor controller can adopt overcurrent protection measures for the IGBT power switching tube.

[0068] In the embodiment of the present application, a computer-readable storage medium is further provided. The computer-readable storage medium stores a computer program. When the processor executes the computer program, it implements the foregoing embodiment of the overcurrent detection method of the motor controller. For example, execute: acquisition of overcurrent faults of IGBT power switching tubes;

[0069] Determine whether each IGBT power switching tube is overcurrent according to the conduction voltage and a preset overcurrent threshold voltage, and output a status signal indicating whether it is overcurrent, where the voltage overcurrent threshold is determined according to the output characteristics of the IGBT power switching tube;

[0070] According to the status signal indicating whether each IGBT power switching tube is overcurrent, when it is confirmed that there is an overcurrent IGBT power switching tube, feedback an overcurrent signal to the motor controller so that the motor controller can adopt overcurrent protection measures for the IGBT power switching tube.

[0071] In the embodiment of the present application, a computer program product is provided. The computer program product includes instructions. When the instructions are run, the method described in the embodiment of the present application is executed. For example, it can executeFigure 5 Each step of the overcurrent detection method of the motor controller shown, for example, performs: acquisition of overcurrent faults of IGBT power switching tubes;

[0072] Determine whether each IGBT power switching tube is overcurrent according to the conduction voltage and a preset overcurrent threshold voltage, and output a status signal indicating whether there is overcurrent, where the voltage overcurrent threshold is determined according to the output characteristics of the IGBT power switching tube;

[0073] According to the status signal indicating whether each IGBT power switching tube is overcurrent, when an overcurrent IGBT power switching tube is confirmed, feedback an overcurrent signal to the motor controller so that the motor controller takes overcurrent protection measures for the IGBT power switching tube.

[0074] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database, or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0075] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as these technical feature combinations do not conflict, they should be considered as within the scope described in this specification.

[0076] The above embodiments only represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. An overcurrent detection system for a motor controller, characterized in that The motor controller includes an inverter circuit, the inverter circuit includes a plurality of IGBT power switching tubes, and the overcurrent detection system includes: A plurality of overcurrent detection modules, which are connected to the plurality of IGBT power switching tubes one by one, and are used to collect the conduction voltage between the collector and the emitter of each IGBT power switching tube, and determine whether each IGBT power switching tube is overcurrent according to the conduction voltage and a preset voltage overcurrent threshold, and output a status signal indicating whether it is overcurrent. Among them, the voltage overcurrent threshold is determined according to the output characteristics of the IGBT power switching tube; A fault logic processing module, which is connected to the plurality of overcurrent detection modules, and is used to feedback an overcurrent signal to the motor controller when it is confirmed that there is an overcurrent IGBT power switching tube according to the status signals output by the plurality of overcurrent detection modules, so that the motor controller can take overcurrent protection measures for the IGBT power switching tube.

2. The overcurrent detection system of the motor controller according to claim 1, characterized in that, The overcurrent detection module includes: A detection unit for the conduction voltage between the collector and the emitter of the IGBT power switching tube, and the detection unit includes an operational amplifier, a conditioning resistor and an isolation diode; A comparator, which is used to compare the conduction voltage between the collector and the emitter of the IGBT power switching tube output by the detection unit with the voltage overcurrent threshold, and output a status signal indicating whether the IGBT power switching tube is overcurrent; A voltage overcurrent threshold setting module, which is used to divide the voltage of the input power supply of the IGBT to obtain the voltage overcurrent threshold. Among them, the magnitude of the voltage division can be changed by adjusting the resistance value of the voltage overcurrent threshold setting module.

3. The overcurrent detection system of the motor controller according to claim 2, wherein The voltage overcurrent threshold setting module includes an adjustable resistor.

4. The overcurrent detection system of the motor controller according to claim 2, wherein The overcurrent detection module further includes: A digital isolation module, which is used to isolate and transmit the status signal indicating whether the IGBT power switching tube is overcurrent to the fault logic processing module.

5. The overcurrent detection system of the motor controller according to claim 4, characterized in that, The digital isolation module includes an integrated digital isolation chip or a discrete opto-electronic coupling chip.

6. The overcurrent detection system of the motor controller according to claim 1, characterized in that The fault logic processing module is specifically used for: When at least one of the status signals output by the plurality of overcurrent detection modules indicates that there is an overcurrent fault in the IGBT power switching tube, feedback an overcurrent signal to the motor controller, so that the motor controller can take overcurrent protection measures for the IGBT power switching tube.

7. A vehicle, characterized in that, Includes: The overcurrent detection system of the motor controller according to any one of claims 1-6.

8. An overcurrent detection method for a motor controller, characterized in that, The motor controller includes an inverter circuit, the inverter circuit includes a plurality of IGBT power switching tubes, and the overcurrent detection includes: Collect the conduction voltage between the collector and the emitter of each IGBT power switching tube; Determine whether each IGBT power switching tube is overcurrent according to the conduction voltage and a preset voltage overcurrent threshold, and output a status signal indicating whether it is overcurrent. Among them, the voltage overcurrent threshold is determined according to the output characteristics of the IGBT power switching tube; According to the status signal indicating whether each IGBT power switching tube is overcurrent, when it is confirmed that there is an overcurrent IGBT power switching tube, feedback an overcurrent signal to the motor controller, so that the motor controller can take overcurrent protection measures for the IGBT power switching tube.

9. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the overcurrent detection method of the motor controller according to claim 8.

10. A computer-readable storage medium, comprising a memory and a computer program stored on the memory and executable on a processor, characterized in that, When the program is executed by the processor, it implements the overcurrent detection method of the motor controller according to claim 8.

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