Overcurrent protection circuit for motor, overcurrent protection method and apparatus for motor, computer device, readable storage medium, and program product

Abstract

An overcurrent protection circuit for a motor, an overcurrent protection method and apparatus for a motor, a computer device, a readable storage medium, and a program product. The overcurrent protection circuit for a motor comprises a first comparator (10), a second comparator (20), a control module (30), a first AND gate module (40), transistors (50), and a current cut-off module (60); when a sampling current is greater than a first current threshold and the control module (30) operates normally, the second comparator (20) outputs a high level to the control module (30), and the control module (30) cuts off a three-phase current of the motor on the basis of the high level; and when the sampling current is greater than the first current threshold and the control module (30) operates abnormally, the first comparator (10) outputs the high level to a second input end of the first AND gate module (40), the control module (30) outputs the high level to a first input end of the first AND gate module (40), the first AND gate module (40) outputs the high level to the transistors (50) to turn on the transistors (50), and the transistors (50) output a low level to the current cut-off module (60) so as to cut off the three-phase current of the motor.

Description

Overcurrent protection circuits for motors, overcurrent protection methods for motors, devices, computer equipment, readable storage media, and software products.

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese patent application CN202410666117.7, filed on May 27, 2024, entitled “Overcurrent protection circuit for motor, overcurrent protection method for motor, device, computer equipment, readable storage medium and program product”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application belongs to the field of computer technology, and in particular relates to an overcurrent protection circuit for an electric motor, an overcurrent protection method for an electric motor, an apparatus, a computer device, a readable storage medium, and a program product. Background Technology

[0004] The motor control module is a crucial component of the drive motor control system in pure electric vehicles. It inverts the DC power from the vehicle battery into three-phase AC power to drive the motor and ultimately propel the vehicle. With the continuous advancement of electric vehicle technology and its widespread application, the control module faces new challenges and opportunities. The safety level of the control module has a significant impact on the overall vehicle safety level. When an overcurrent fault occurs in the motor during vehicle operation, the control module detects the overcurrent fault and executes a safety shutdown function.

[0005] Currently, when the control module detects an overcurrent fault in the motor, it can use software control to execute the safety shutdown function or control the hardware circuit to execute the safety shutdown function. However, when the software control fails or the hardware circuit control fails, it cannot provide overcurrent protection for the motor. The existing solution has very low reliability for overcurrent protection of the motor.

[0006] Summary of the Invention

[0007] This application provides an overcurrent protection circuit, method, apparatus, computer device, readable storage medium, and program product for motors that can provide reliable overcurrent protection for motors, in order to solve the above-mentioned technical problems.

[0008] In a first aspect, this application provides an overcurrent protection circuit for a motor, comprising: a first comparator, a second comparator, a control module, a first AND gate module, a transistor, and a current cutting-off module: the input terminals of the first comparator and the second comparator are both used to input the sampled current of the motor; the output terminal of the second comparator is connected to the input terminal of the control module; the output terminal of the control module is connected to the first input terminal of the first AND gate module; the output terminal of the first comparator is connected to the second input terminal of the first AND gate module; the output terminal of the first AND gate module is connected to one end of the transistor; and the other end of the transistor is connected to the input terminal of the current cutting-off module.

[0009] When the sampled current is greater than the first current threshold and the control module is operating normally, the second comparator outputs a high level to the input terminal of the control module, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator.

[0010] When the sampled current is greater than the first current threshold and the control module is malfunctioning, the first comparator outputs a high level to the second input terminal of the first AND gate module, the control module outputs a high level to the first input terminal of the first AND gate module, the output terminal of the first AND gate module outputs a high level to one end of the transistor, causing the transistor to conduct. After the transistor conducts, the other end of the transistor outputs a low level to the current switching module, and the current switching module cuts off the three-phase current of the motor based on the low input level.

[0011] In one embodiment, the transistor is an N-type metal-oxide-semiconductor field-effect transistor, one end of the transistor is the source of the transistor, the other end of the transistor is the drain of the transistor, the other end of the transistor is also connected to a power supply, and the gate of the transistor is grounded.

[0012] In one embodiment, when the sampling current is greater than a first current threshold and the control module is operating normally, the output of the first comparator outputs a high level to the second input of the first AND gate module, the output of the control module outputs a low level to the first input of the first AND gate module, the output of the first AND gate module outputs a low level to one end of the transistor, causing the transistor to be turned off, and after the transistor is turned off, the other end of the transistor outputs a high level to the current switching module.

[0013] In one embodiment, when the sampled current is greater than a second current threshold and less than a first current threshold, the second comparator outputs a high level to the input of the control module, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator; wherein, the second current threshold is less than the first current threshold.

[0014] In one embodiment, the current switching module includes a second AND gate module and a third AND gate module; the first input terminal of the second AND gate module and the first input terminal of the third AND gate module are connected to the other end of the transistor;

[0015] The first input terminal of the second AND gate module receives the low level output by the transistor, and the output terminal of the second AND gate module outputs a low level to cut off the three-phase current of the motor;

[0016] The first input terminal of the third AND gate module receives the low level output by the transistor, and the output terminal of the third AND gate module outputs a low level to cut off the three-phase current of the motor.

[0017] Secondly, this application provides an overcurrent protection method for a motor, the method comprising:

[0018] The sampled current of the motor is obtained, and the sampled current is input into the first comparator and the second comparator;

[0019] When the sampled current is greater than the first current threshold and the control module is operating normally, the second comparator outputs a high level to the input terminal of the control module, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator.

[0020] When the sampled current is greater than the first current threshold and the control module is malfunctioning, the first comparator outputs a high level to the second input terminal of the first AND gate module, the control module outputs a high level to the first input terminal of the first AND gate module, and the output terminal of the first AND gate module outputs a high level to one end of the transistor, causing the transistor to conduct. After the transistor conducts, the other end of the transistor outputs a low level to the current switching module, and the current switching module cuts off the three-phase current of the motor based on the low input level.

[0021] Thirdly, this application provides an overcurrent protection device for a motor, comprising:

[0022] The acquisition module is used to acquire the sampled current of the motor and input the sampled current into the first comparator and the second comparator;

[0023] The first cut-off module is used to output a high level to the input terminal of the control module through the second comparator when the sampled current is greater than the first current threshold and the control module is operating normally, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator.

[0024] The second cutoff module is used to, when the sampled current is greater than the first current threshold and the control module is malfunctioning, output a high level to the second input terminal of the first AND gate module through the first comparator, output a high level to the first input terminal of the first AND gate module through the control module, output a high level to one end of the transistor through the output terminal of the first AND gate module to turn on the transistor, and output a low level to the current switching module through the other end of the transistor after the transistor is turned on, and cut off the three-phase current of the motor based on the low input level through the current switching module.

[0025] Fourthly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the methods of the various embodiments.

[0026] Fifthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the methods of the various embodiments.

[0027] Sixthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the methods of the various embodiments.

[0028] The aforementioned motor overcurrent protection circuit, method, device, computer equipment, readable storage medium, and program product, when the sampled current is greater than the first current threshold and the control module is operating normally (indicating that the control module can perform software control normally), the second comparator outputs a high level to the input terminal of the control module. The control module, based on the high level output of the second comparator, cuts off the three-phase current of the motor. The controller cuts off the three-phase current according to the software control logic, thus providing overcurrent protection for the motor. When the sampled current is greater than the first current threshold and the control module is operating abnormally (indicating that the control module's software control has failed), the first comparator outputs a high level to the second input terminal of the first AND gate module, the control module outputs a high level to the first input terminal of the first AND gate module, and the output terminal of the first AND gate module outputs a high level to one end of a transistor, causing the transistor to conduct. After the transistor conducts, the other end of the transistor outputs a low level to the current switching module. Thus, the current switching module, based on the low input level, cuts off the three-phase current of the motor, achieving overcurrent protection for the motor through hardware control. As can be seen, this application provides overcurrent protection for the motor according to the software control logic when the control module is operating normally, and provides overcurrent protection for the motor through hardware control when the control module is operating abnormally. It integrates dual overcurrent protection of software control and hardware control, thereby improving the reliability of overcurrent protection for the motor. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 is a schematic diagram of the motor control system in one embodiment;

[0031] Figure 2 is a schematic diagram of an overcurrent protection circuit in one embodiment;

[0032] Figure 3 is a schematic diagram of the overcurrent protection circuit in another embodiment;

[0033] Figure 4 is a flowchart illustrating an overcurrent protection method for a motor in one embodiment;

[0034] Figure 5 is a schematic diagram of the overcurrent protection device for a motor in one embodiment;

[0035] Figure 6 is an internal structure diagram of a computer device in one embodiment. Detailed Implementation

[0036] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0037] It should be noted that the term "multiple" in the embodiments of the present invention refers to two or more. Therefore, "multiple" can also be understood as "at least two" in the embodiments of the present invention. "And / or" describes the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following associated objects have an "or" relationship.

[0038] Currently, when the control module detects an overcurrent fault in the motor, it can use software to execute a safety shutdown function. However, if the software is unreliable, or if the program crashes or malfunctions, the motor overcurrent protection will fail, posing a risk of motor damage. Alternatively, it can control the safety shutdown function through hardware circuitry, but hardware modules also have a certain failure rate; if components in the circuit fail, the motor overcurrent protection will also fail, risking motor damage as well. Therefore, a highly reliable overcurrent protection circuit is needed.

[0039] As shown in Figure 1, the motor control system of this application consists of a power supply unit, a control unit, a drive unit, a power unit, and an information sampling unit. The information sampling unit includes a current sampling unit and a bus voltage sampling unit, and the control unit includes an overcurrent protection circuit. The power supply unit supplies power to the control unit and communicates with the control unit via a synchronous serial peripheral interface (SPI). When the control unit detects a fault, it can promptly shut off the power supply to protect the circuit system, exhibiting the highest safety protection priority. The control unit detects signals such as the bus voltage from the bus voltage sampling unit, the three-phase current from the current sampling unit, the active short circuit (ASC) of the drive unit, and the fault of the drive unit bridge arm. When a fault occurs, the control unit performs the corresponding safety shutdown operation. The control unit can also control the output of a pulse width modulation (PWM) signal to the drive unit, and the drive unit controls the output of a PWM signal to the power unit. The power unit includes six transistors 50, namely Q1, Q2, Q3, Q4, Q5, and Q6, and the power module is connected to the motor (corresponding to M in the figure).

[0040] When the three-phase current exceeds the threshold, the overcurrent protection circuit can realize the overcurrent protection function. The overcurrent protection function of the overcurrent protection circuit will be explained in detail below.

[0041] In an exemplary embodiment, as shown in FIG2, an overcurrent protection circuit for a motor is provided, including a first comparator 10, a second comparator 20, a control module 30, a first AND gate module 40, a transistor 50, and a current cutting-off module 50: the input terminals of the first comparator 10 and the second comparator 20 are both used to input the sampled current of the motor; the output terminal of the second comparator 20 is connected to the input terminal of the control module 30; the output terminal of the control module 30 is connected to the first input terminal of the first AND gate module 40; the output terminal of the first comparator 10 is connected to the second input terminal of the first AND gate module 40; the output terminal of the first AND gate module 40 is connected to one end of the transistor 50; and the other end of the transistor 50 is connected to the input terminal of the current cutting-off module 50; when the sampled current is large... When the first current threshold is met and the control module 30 is operating normally, the second comparator 20 outputs a high level to the input terminal of the control module 30, and the control module 30 cuts off the three-phase current of the motor based on the high level output by the second comparator 20. When the sampled current is greater than the first current threshold and the control module 30 is operating abnormally, the first comparator 10 outputs a high level to the second input terminal of the first AND gate module 40, the control module 30 outputs a high level to the first input terminal of the first AND gate module 40, and the output terminal of the first AND gate module 40 outputs a high level to one end of the transistor 50, causing the transistor 50 to conduct. After the transistor 50 conducts, the other end of the transistor 50 outputs a low level to the current switching module, and the current switching module cuts off the three-phase current of the motor based on the low level input.

[0042] The input terminals of the first comparator 10 and the second comparator 20 are both used to input the sampled current of the motor. Specifically, the first input terminal of the first comparator 10 and the first input terminal of the second comparator 20 are both used to input the sampled current of the motor.

[0043] The second input terminal of the first comparator 10 is connected to the first input terminal of the controller, and the second input terminal of the second comparator 20 is connected to the second input terminal of the controller;

[0044] The output of the second comparator 20 is connected to the input of the control module 30, specifically: the output of the second comparator 20 is connected to the third input of the control module 30.

[0045] In this embodiment, the current threshold of the first comparator 10 is greater than the current threshold of the second comparator 20. The current threshold of any comparator is a set voltage value. When the voltage of the input signal is higher than this set voltage value, the comparator will output a high level, and when the voltage of the input signal is lower than this set voltage value, the comparator will output a low level.

[0046] The control module 30 has a self-test function, which will check whether its internal program code is running normally. If it is running normally, the control module 30 is running normally and outputs a low level. Otherwise, the control module 30 is running abnormally and outputs a high level.

[0047] The first current threshold is the current threshold of the first comparator 10.

[0048] If the sampled current is greater than the first current threshold and the control module 30 is operating normally, it means that the control module 30 can perform software control normally to switch the three-phase current of the motor. Then, the second comparator 20 compares the sampled current with the current threshold corresponding to the second comparator 20, determines that the sampled current is greater than the current threshold corresponding to the second comparator 20, and outputs a high level to the input terminal of the control module 30. The control module 30 adjusts the PWM signal based on the high level output by the second comparator 20, thereby cutting off the three-phase current of the motor.

[0049] If the sampled current is greater than the first current threshold and the control module 30 is malfunctioning, it means that the control module 30 cannot perform normal software control to switch the three-phase current of the motor. Then, the first comparator 10 compares the sampled current with the current threshold corresponding to the first comparator 10 and determines that the sampled current is greater than the current threshold corresponding to the first comparator 10. The first comparator 10 outputs a high level to the second input terminal of the first AND gate module 40, and the control module 30 outputs a high level to the first input terminal of the first AND gate module 40. At this time, the output terminal of the first AND gate module 40 outputs a high level to one end of the transistor 50, making the transistor 50 conduct. After the transistor 50 conducts, the other end of the transistor 50 outputs a low level to the current switching module. The current switching module adjusts the PWM signal based on the low input level, thereby cutting off the three-phase current of the motor.

[0050] As can be seen, when the sampled current is greater than the first current threshold and the control module 30 is operating normally, it indicates that the control module 30 can perform software control normally. In this case, the second comparator 20 outputs a high level to the input terminal of the control module 30. Based on the high level output of the second comparator 20, the control module 30 cuts off the three-phase current of the motor. The controller cuts off the three-phase current according to the software control logic, thus providing overcurrent protection for the motor. When the sampled current is greater than the first current threshold and the control module 30 is operating abnormally, it indicates that the software control of the control module 30 has failed. In this case, the first comparator 10 outputs a high level to the second input terminal of the first AND gate module 40, the control module 30 outputs a high level to the first input terminal of the first AND gate module 40, and the output terminal of the first AND gate module 40 outputs a high level to one end of the transistor 50, causing the transistor 50 to conduct. After the transistor 50 conducts, the other end of the transistor 50 outputs a low level to the current switching module. Thus, the current switching module cuts off the three-phase current of the motor based on the low input level, realizing overcurrent protection for the motor through hardware control of cutting off the three-phase current. As can be seen, when the control module 30 is operating normally, this application provides overcurrent protection for the motor according to the software control logic. When the control module 30 is operating abnormally, it can also provide overcurrent protection for the motor through hardware control. This integrates dual overcurrent protection of software control and hardware control, thereby improving the reliability of overcurrent protection for the motor.

[0051] In one embodiment, transistor 50 is an N-type metal-oxide-semiconductor field-effect transistor 50, one end of transistor 50 is the source of transistor 50, the other end of transistor 50 is the drain of transistor 50, the other end of transistor 50 is also connected to a power supply, and the gate of transistor 50 is grounded.

[0052] In this embodiment, the source of transistor 50 is connected to the output of the first AND gate module 40, the drain of transistor 50 is connected to the power supply through resistor R1, and the gate of transistor 50 is grounded. When the source is connected to a low level, the current I between the source and the gate... GS When the voltage is less than the corresponding threshold, transistor 50 is turned off, and the source of transistor 50 outputs a high level; when the source is connected to a high level, the current I between the source and the gate... GS When the threshold value is greater than the corresponding threshold, transistor 50 is turned on, and the source of transistor 50 outputs a low level.

[0053] In one embodiment, when the sampling current is greater than the first current threshold and the control module 30 is operating normally, the output of the first comparator 10 outputs a high level to the second input of the first AND gate module 40, the output of the control module 30 outputs a low level to the first input of the first AND gate module 40, the output of the first AND gate module 40 outputs a low level to one end of the transistor 50, causing the transistor 50 to be turned off, and after the transistor 50 is turned off, the other end of the transistor 50 outputs a high level to the current switching module.

[0054] When the sampled current is greater than the first current threshold and the control module 30 is operating normally, the first comparator 10 compares the sampled current with the current threshold corresponding to the first comparator 10, determines that the sampled current is greater than the current threshold corresponding to the first comparator 10, and the first comparator 10 outputs a high level to the second input terminal of the first AND gate module 40. At the same time, when the control module 30 is operating normally, the control module 30 outputs a low level to the first input terminal of the first AND gate module 40. At this time, the output terminal of the first AND gate module 40 outputs a low level to the source of the transistor 50, the transistor 50 is turned off, and the drain of the transistor 50 outputs a high level to the current switching module. After receiving the high level, the current switching module will not cut off the three-phase current of the motor. At this time, there is no situation where the three-phase current of the motor is cut off by hardware control, and the software overcurrent protection is not affected.

[0055] In one embodiment, when the sampled current is greater than the second current threshold and less than the first current threshold, the second comparator 20 outputs a high level to the input terminal of the control module 30, and the control module 30 cuts off the three-phase current of the motor based on the high level output by the second comparator 20; wherein, the second current threshold is less than the first current threshold.

[0056] In this embodiment, the second current threshold is the current threshold corresponding to the second comparator 20. When the sampled current is greater than the second current threshold and less than the first current threshold, the second comparator 20 compares the sampled current with the current threshold corresponding to the second comparator 20 to determine that the sampled current is greater than the current threshold corresponding to the second comparator 20. The second comparator 20 outputs a high level to the input terminal of the control module 30, and the control module 30 operates normally. The control module 30 adjusts the PWM signal based on the high level output by the second comparator 20, thereby cutting off the three-phase current of the motor.

[0057] In this embodiment, the second current threshold and the first current threshold are configured by the configuration personnel through the control module 30.

[0058] As can be seen, when the sampled current is greater than the second current threshold and less than the first current threshold, this application realizes the overcurrent protection of the motor through the comparator and the control module 30, and realizes the overcurrent protection of the motor through software control.

[0059] In one embodiment, when the sampled current is less than the second current threshold, the motor does not experience an overcurrent fault, and the control module 30 executes the normal control strategy.

[0060] In one embodiment, the current switching module includes a second AND gate module and a third AND gate module; the first input terminal of the second AND gate module and the other end of the first input terminal of the third AND gate module are connected; the first input terminal of the second AND gate module receives a low level output by the transistor 50, and the output terminal of the second AND gate module outputs a low level to cut off the three-phase current of the motor; the first input terminal of the third AND gate module receives a low level output by the transistor 50, and the output terminal of the third AND gate module outputs a low level to cut off the three-phase current of the motor.

[0061] The level signal output from the drain stage of transistor 50 is ANDed with the upper bridge drive signal (PWM-H) and lower bridge drive signal (PWM-L) of the motor U phase, respectively, which will directly pull the drive signal low and control the U phase that has a fault to be safely shut down;

[0062] The level signal output from the drain of transistor 50 is ANDed with the upper bridge drive signal (PWM-H) and lower bridge drive signal (PWM-L) of the V phase of the motor, respectively. This will directly pull the drive signal low and control the V phase that has a fault to be safely shut down.

[0063] The level signal output from the drain stage of transistor 50 is ANDed with the upper bridge drive signal (PWM-H) and lower bridge drive signal (PWM-L) of the W phase of the motor, respectively. This will directly pull the drive signal low and control the W phase that has a fault to be safely shut down.

[0064] Referring to Figure 3, which is a schematic diagram of an overcurrent protection circuit in another embodiment, Ref1 is the current threshold corresponding to the first comparator, which is a hardware overcurrent threshold, and Ref2 is the current threshold corresponding to the second comparator, which is a software overcurrent threshold. The microcontroller unit (MCU) corresponds to the control module described above. The MCU outputs a status signal to indicate the MCU's operating status. When the MCU is malfunctioning, the output status signal is a high-level signal, and when the MCU is operating normally, the output status signal is a low-level signal. M1 is a transistor.

[0065] The motor's sampling current is sampled by the current sampling unit and flows through comparator 1 and comparator 2. When the sampled current is less than Ref2, the motor has not experienced an overcurrent fault, and the control unit executes the normal control strategy.

[0066] When the sampled current is greater than Ref2 and less than Ref1, comparator 2 outputs a high level to the MCU, and the MCU executes the corresponding safety shutdown function and software overcurrent protection function.

[0067] When the sampled current is greater than Ref1, if the MCU self-test result is normal, comparator 2 outputs a high level to the MCU to execute the software overcurrent protection function. At the same time, comparator 1 outputs a high level to AND gate 3, the MCU outputs a low level status signal to AND gate 3, and AND gate 3 outputs a low level to the source of transistor M1, and the transistor current I... GS When the current is less than the corresponding threshold, the transistor is turned off, and the drain output overcurrent signal VDC1 of M1 is high, which does not affect the software overcurrent protection.

[0068] When the current is greater than Ref1, if the MCU self-test result is abnormal, comparator 1 outputs a high level, AND gate 3 outputs a high level to AND gate 3, the MCU outputs a status signal high level to AND gate 3, AND gate 3 outputs a high level to the source of transistor M1, and the current I of transistor M1... GS When the current exceeds the corresponding threshold, the transistor turns on, and the drain output of M1, the overcurrent signal VDC1, is low. The overcurrent signal is ANDed with the upper and lower bridge drive signals of the three phases of the motor, which directly pulls the drive signal low and controls the U phase that has malfunctioned to be safely shut down.

[0069] As can be seen, the overcurrent protection circuit of this application integrates both software and hardware overcurrent protection. When the software overcurrent protection fails, it can switch to hardware overcurrent protection, which improves the reliability of motor overcurrent protection and enhances the safety level.

[0070] At the same time, the hardware overcurrent protection circuit has fewer components and a lower hardware failure rate, which can reduce the cost of some hardware circuits.

[0071] Referring to Figure 4, this application also provides an overcurrent protection method for a motor, the method comprising:

[0072] Step 402: Obtain the sampled current of the motor and input the sampled current into the first comparator and the second comparator of the motor;

[0073] Step 405: When the sampled current is greater than the first current threshold and the control module in the motor is operating normally, the second comparator outputs a high level to the input terminal of the control module, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator.

[0074] Step 406: When the sampled current is greater than the first current threshold and the control module is malfunctioning, the first comparator outputs a high level to the second input terminal of the first AND gate module in the motor, the control module outputs a high level to the first input terminal of the first AND gate module, and the output terminal of the first AND gate module outputs a high level to one end of the transistor in the motor, causing the transistor to conduct. After the transistor conducts, the other end of the transistor outputs a low level to the current switching module of the motor, and the current switching module cuts off the three-phase current of the motor based on the low input level.

[0075] In this embodiment, the overcurrent protection method can be applied to the overcurrent protection circuit described above. The first comparator, the second comparator, the control module, the first AND gate module, the transistor, and the current switching module are all included in the overcurrent protection circuit. The connection relationship between the first comparator, the second comparator, the control module, the first AND gate module, the transistor, and the current switching module is described with reference to the corresponding embodiment in the overcurrent protection circuit described above.

[0076] The specific implementation of this embodiment can be referred to the corresponding description of the overcurrent protection circuit above, and will not be repeated here.

[0077] As can be seen, when the sampled current is greater than the first current threshold and the control module is operating normally, it indicates that the control module can perform software control normally. In this case, the second comparator outputs a high level to the input terminal of the control module. The control module cuts off the three-phase current of the motor based on the high level output of the second comparator. The controller cuts off the three-phase current according to the software control logic, thus providing overcurrent protection for the motor. When the sampled current is greater than the first current threshold and the control module is operating abnormally, it indicates that the software control of the control module has failed. In this case, the first comparator outputs a high level to the second input terminal of the first AND gate module. The control module outputs a high level to the first input terminal of the first AND gate module. The output terminal of the first AND gate module outputs a high level to one end of the transistor, turning the transistor on. After the transistor is turned on, the other end of the transistor outputs a low level to the current switching module. Thus, the current switching module cuts off the three-phase current of the motor based on the low input level, achieving overcurrent protection for the motor through hardware control of cutting off the three-phase current. As can be seen, this application provides overcurrent protection for the motor according to the software control logic when the control module is operating normally, and provides overcurrent protection for the motor through hardware control when the control module is operating abnormally. It integrates dual overcurrent protection of software control and hardware control, thereby improving the reliability of overcurrent protection for the motor.

[0078] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0079] Based on the same inventive concept, this application also provides an overcurrent protection device for a motor to implement the overcurrent protection method for the motor described above. The solution provided by this device is similar to the solution described in the above method. Therefore, the specific limitations of one or more embodiments of the overcurrent protection device for motors provided below can be found in the limitations of the overcurrent protection method for motors described above, and will not be repeated here.

[0080] In an exemplary embodiment, as shown in FIG5, an overcurrent protection device 500 for a motor is provided, comprising:

[0081] The acquisition module 501 is used to acquire the sampled current of the motor and input the sampled current into the first comparator and the second comparator;

[0082] The first cut-off module 502 is used to output a high level to the input terminal of the control module through the second comparator when the sampled current is greater than the first current threshold and the control module is operating normally, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator.

[0083] The second cutoff module 503 is used to, when the sampled current is greater than the first current threshold and the control module is malfunctioning, output a high level to the second input terminal of the first AND gate module through the first comparator, output a high level to the first input terminal of the first AND gate module through the control module, output a high level to one end of the transistor through the output terminal of the first AND gate module to turn on the transistor, and output a low level to the current switching module through the other end of the transistor after the transistor is turned on, and cut off the three-phase current of the motor based on the low input level through the current switching module.

[0084] The various modules in the aforementioned overcurrent protection device for the motor can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0085] In an exemplary embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram is shown in Figure 6. The computer device includes a processor, memory, input / output interface, communication interface, display unit, and input device. The processor, memory, and input / output interface are connected via a system bus, and the communication interface, display unit, and input device are also connected to the system bus via the input / output interface. The processor of the computer device provides computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The input / output interface of the computer device is used for exchanging information between the processor and external devices. The communication interface of the computer device is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, Near Field Communication (NFC), or other technologies. When the computer program is executed by the processor, it implements an overcurrent protection method for a motor. The display unit of the computer device is used to form a visually visible image and may be a display screen, a projection device, or a virtual reality imaging device. The display screen can be an LCD screen or an e-ink screen. The input device of the computer device can be a touch layer covering the display screen, or buttons, trackballs, or touchpads set on the casing of the computer device, or external keyboards, touchpads, or mice, etc.

[0086] Those skilled in the art will understand that the structure shown in Figure 6 is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0087] In one exemplary embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.

[0088] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps in the above method embodiments.

[0089] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0090] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0091] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0092] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0093] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An overcurrent protection circuit for an electric machine, characterized in that The application relates to a current cut-off module for a motor, which comprises a first comparator, a second comparator, a control module, a first AND gate module, a transistor and the current cut-off module; the input end of the first comparator and the input end of the second comparator are used for inputting a sampling current of the motor; the output end of the second comparator is connected with the input end of the control module; the output end of the control module is connected with the first input end of the first AND gate module; the output end of the first comparator is connected with the second input end of the first AND gate module; the output end of the first AND gate module is connected with one end of the transistor; the other end of the transistor is connected with the input end of the current cut-off module. When the sampling current is greater than a first current threshold value and the control module is normal, the second comparator outputs a high level to the input end of the control module, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator. When the sampling current is greater than the first current threshold value and the control module is abnormal, the first comparator outputs a high level to the second input end of the first AND gate module, the control module outputs a high level to the first input end of the first AND gate module, the output end of the first AND gate module outputs a high level to one end of the transistor, so that the transistor is turned on, and the other end of the transistor outputs a low level to the current cut-off module after the transistor is turned on, and the current cut-off module cuts off the three-phase current of the motor based on the input low level.

2. The overcurrent protection circuit of claim 1, wherein, The transistor is an N-type metal oxide semiconductor field effect transistor, one end of the transistor is a source electrode of the transistor, the other end of the transistor is a drain level of the transistor, the other end of the transistor is also connected with a power supply, and the gate of the transistor is grounded.

3. The overcurrent protection circuit according to claim 1 or 2, characterized in that, When the sampling current is greater than the first current threshold value and the control module is normal, the output end of the first comparator outputs a high level to the second input end of the first AND gate module, the output end of the control module outputs a low level to the first input end of the first AND gate module, the output end of the first AND gate module outputs a low level to one end of the transistor, so that the transistor is turned off, and the other end of the transistor outputs a high level to the current cut-off module after the transistor is turned off.

4. The overcurrent protection circuit according to claim 1 or 2, characterized in that, When the sampling current is greater than a second current threshold value and less than the first current threshold value, the second comparator outputs a high level to the input end of the control module, and the control module cuts off the three-phase current of the motor based on the high level output by the second comparator; wherein the second current threshold value is less than the first current threshold value.

5. The overcurrent protection circuit according to claim 1 or 2, characterized in that, The current cut-off module comprises a second AND gate module and a third AND gate module; one end of the transistor is connected with the first input end of the second AND gate module and the first input end of the third AND gate module; The first input end of the second AND gate module receives the low level output by the transistor, and the output end of the second AND gate module outputs a low level to cut off the three-phase current of the motor; The first input end of the third AND gate module receives the low level output by the transistor, and the output end of the third AND gate module outputs a low level to cut off the three-phase current of the motor. The first input end of the third AND gate module receives the low level of the transistor output, and the output end of the third AND gate module outputs a low level to cut off the three-phase current of the motor.

6. A method of overcurrent protection of an electric machine, characterized in that The method comprises: acquiring a sampling current of the motor and inputting the sampling current into a first comparator and a second comparator; in a case where the sampling current is greater than a first current threshold and the control module is running normally, outputting a high level from the second comparator to an input end of the control module, and cutting off the three-phase current of the motor by the control module based on the high level output by the second comparator; in a case where the sampling current is greater than the first current threshold and the control module is running abnormally, outputting a high level from the first comparator to a second input end of a first AND gate module, outputting a high level from the control module to a first input end of the first AND gate module, outputting a high level from an output end of the first AND gate module to one end of a transistor to make the transistor conduct, outputting a low level from the other end of the transistor to a current switching module after the transistor is turned on, and cutting off the three-phase current of the motor by the current switching module based on the input low level.

7. An overcurrent protection device for an electric machine, characterized in that comprise: an acquisition module configured to acquire a sampling current of the motor and input the sampling current into a first comparator and a second comparator; a first cutting-off module configured to, in a case where the sampling current is greater than a first current threshold and a control module is running normally, output a high level from the second comparator to an input end of the control module, and cut off the three-phase current of the motor by the control module based on the high level output by the second comparator; a second cutting-off module configured to, in a case where the sampling current is greater than the first current threshold and the control module is running abnormally, output a high level from the first comparator to a second input end of a first AND gate module, output a high level from the control module to a first input end of the first AND gate module, output a high level from an output end of the first AND gate module to one end of a transistor to make the transistor conduct, output a low level from the other end of the transistor to a current switching module after the transistor is turned on, and cut off the three-phase current of the motor by the current switching module based on the input low level. 8.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-7. The processor executes the computer program to implement the steps of the method of any one of claims 1 to 6.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 6.

10. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the steps of the method of any one of claims 1 to 6.

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