Short-circuit protection control system and control method for motor and vehicle

Abstract

The invention discloses a short-circuit protection control system and method for a motor and a vehicle. The short-circuit protection control system comprises a motor controller, a power module, an isolation transmission module, a voltage conversion module and a first controller. The motor controller is configured to control the power module to output a driving signal to the motor; the isolation transmission module is configured to obtain a high-voltage alternating current signal generated by the motor and transmit the high-voltage alternating current signal to the voltage conversion module in an isolation manner; the voltage conversion module is also electrically connected with the motor controller and the power module; the first controller is configured to obtain the phase voltage frequency of the motor and output a protection control signal to the voltage conversion module according to the phase voltage frequency; and the voltage conversion module is further configured to control the working states of the power module and the motor controller according to the protection control signal, so that quick response and effective protection of motor control and power module short-circuit protection actions are realized, the system implementation complexity is reduced, the software condition judgment and control process is simplified, and the overall cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and in particular, to a short-circuit protection control system, a control method and a vehicle for a motor. Background Art

[0002] During the operation of a motor, a phenomenon of runaway may occur, that is, the speed of the motor exceeds the normal operating range. When the motor runs away, a large back electromotive force will be generated, which will cause components such as bus capacitors in the motor controller to break down and cause irreversible damage.

[0003] Active short-circuit protection is an important safety measure in a motor control system, which is used to protect the safety of the motor and the vehicle when the motor runs at high speed. When the motor runs away, the active short circuit (ASC) protection technology is usually adopted to prevent the power module from being broken down due to overvoltage.

[0004] However, in the prior art, the motor controller is powered by a low-voltage side power supply. Under specific working conditions (such as the condition of coasting in neutral on a long downhill slope), the low-voltage side power supply will lose power. At this time, the motor controller cannot perform active short-circuit protection, resulting in the breakdown and damage of the motor controller and the power module due to the back electromotive force caused by the motor running at high speed. Moreover, the motor controller usually needs to determine whether to enter the short-circuit protection state by means of software conditions and rely on software control to enter the short-circuit protection state. The implementation means are relatively complex, and the protection ability for extreme situations is weak. Summary of the Invention

[0005] The present invention provides a short-circuit protection control system, a control method and a vehicle for a motor, so as to achieve a rapid response of active short-circuit protection when the motor runs away or at high speed and avoid overvoltage damage to the motor controller.

[0006] According to an aspect of the present invention, there is provided a short-circuit protection control system for a motor, including: a motor controller, a power module, an isolation transmission module, a voltage conversion module and a first controller;

[0007] The power module is respectively electrically connected to the motor controller and the motor; the motor controller is configured to control the power module to output a driving signal to the motor;

[0008] The isolation transmission module is respectively electrically connected to the motor and the voltage conversion module, and the voltage conversion module is also electrically connected to the power supply terminal of the first controller; the isolation transmission module is configured to acquire a high-voltage AC signal generated by the motor and isolate and transmit the high-voltage AC signal to the voltage conversion module; the voltage conversion module is configured to output a first voltage signal to the power supply terminal of the first controller according to the high-voltage AC signal;

[0009] The input end of the first controller is electrically connected to the motor, and the control output end of the first controller is electrically connected to the voltage conversion module; the voltage conversion module is also electrically connected to the motor controller and the power module;

[0010] The first controller is configured to obtain the phase voltage frequency of the motor and output a protection control signal to the voltage conversion module according to the phase voltage frequency;

[0011] The voltage conversion module is also configured to control the working states of the power module and the motor controller according to the protection control signal.

[0012] Optionally, the voltage conversion module includes a rectification module and a DCDC module;

[0013] The rectification module is electrically connected between the isolation transmission module and the DCDC module; the rectification module is used to output a high-voltage DC signal to the DCDC module according to the high-voltage AC signal;

[0014] The DCDC module is also electrically connected to the power supply end and the control output end of the first controller, and the DCDC module is also electrically connected to the motor controller and the power module;

[0015] The DCDC module is used to output a first voltage signal to the power supply end of the first controller according to the high-voltage DC signal; and the DCDC module is also used to control the working states of the power module and the motor controller according to the protection control signal provided by the first controller.

[0016] Optionally, the voltage conversion module further includes a transformer;

[0017] The transformer is electrically connected between the isolation transmission module and the rectification module.

[0018] Optionally, the voltage conversion module further includes a voltage stabilization module;

[0019] The voltage stabilization module is electrically connected between the rectification module and the DCDC module.

[0020] Optionally, the isolation transmission module is electrically connected to at least one phase of the three-phase stator winding of the motor and is configured to obtain the high-voltage AC signal of at least one phase of the motor.

[0021] Optionally, the first controller is electrically connected to at least two phases of the three-phase stator winding of the motor;

[0022] The first controller is further configured to obtain the phase voltage signal of the motor and obtain the phase voltage frequency according to the phase voltage signal.

[0023] Optionally, the first controller is further configured to output an enabling level of the protection control signal when the phase voltage frequency exceeds a frequency threshold, so that the voltage conversion module controls the operating state of the power module to be in a three-phase short-circuit protection mode according to the enabling level of the protection control signal, and controls the operating state of the motor controller to be in a fault mode.

[0024] Optionally, the isolation transmission module includes at least one of an optocoupler chip, a magnetic coupler chip, and a digital isolation chip.

[0025] According to another aspect of the present invention, there is provided a short-circuit protection control method for a motor, which is executed by a first controller in the short-circuit protection control system of the above-mentioned motor, and includes:

[0026] Obtain the phase voltage signal of the motor;

[0027] Obtain the phase voltage frequency according to the phase voltage signal;

[0028] When the phase voltage frequency is greater than the frequency threshold, output an enabling level of the protection control signal, so that the voltage conversion module controls the power module to enter the short-circuit protection mode according to the enabling level of the protection control signal, and controls the motor controller to enter the fault mode.

[0029] According to another aspect of the present invention, there is provided a vehicle, including: a motor and the above-mentioned short-circuit protection control system of the motor.

[0030] The short-circuit protection control system of the motor provided by the embodiment of the present invention can achieve electrical isolation between the voltage conversion module and the motor by configuring the isolation transmission module to obtain the high-voltage AC signal generated by the motor and isolate and transmit the high-voltage AC signal to the voltage conversion module, ensuring that the voltage conversion module and the subsequent circuits are not affected under abnormal high voltage conditions of the motor, improving the overall safety of the system. By configuring the voltage conversion module to output a first voltage signal to the power supply terminal of the first controller according to the high-voltage AC signal, it is not necessary to separately set a power supply for the first controller, which is beneficial to cost reduction, and reliable power supply to the first controller can be achieved both when the motor speed is normal or overspeed, and the power module can be reliably controlled to perform a three-phase short-circuit protection action to achieve reliable protection of the motor controller and the power module. Additionally, by configuring the first controller to obtain the phase voltage frequency of the motor and output a protection control signal to the voltage conversion module according to the phase voltage frequency, and enabling the voltage conversion module to control the working states of the power module and the motor controller according to the protection control signal, the power module can be controlled to perform a short-circuit protection action when the motor speed is too high to protect the motor controller and the power module from being reversely broken down, realizing fast response and effective protection of the motor control and the power module protection action. And through the independent first controller for autonomous control, complex software condition judgment and control processes of the motor controller are avoided, the complexity of system implementation is reduced, the software condition judgment and control processes are simplified, the overall cost is reduced, and the cost performance and market competitiveness of the protection system are improved.

[0031] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. Brief Description of the Drawings

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 is a schematic structural diagram of a motor control system provided by an embodiment of the present invention;

[0034] Figure 2 is a schematic structural diagram of another motor control system provided by an embodiment of the present invention;

[0035] Figure 3 is a flowchart of a motor control method provided by an embodiment of the present invention. Detailed Embodiments

[0036] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0037] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0038] Figure 1 is a schematic structural diagram of a short-circuit protection control system for a motor provided by an embodiment of the present invention, as Figure 1 shown, the short-circuit protection control system for the motor includes: a motor controller 10, a power module 20, an isolation transmission module 30, a voltage conversion module 40, and a first controller 50; the power module 20 is electrically connected to the motor controller 10 and the motor M respectively; the motor controller 10 is configured to control the power module 20 to output a drive signal to the motor M; the isolation transmission module 30 is electrically connected to the motor M and the voltage conversion module 40 respectively, and the voltage conversion module 40 is also electrically connected to the power supply terminal VDD of the first controller 10; the isolation transmission module 30 is configured to obtain a high-voltage AC signal generated by the motor M and isolate and transmit the high-voltage AC signal to the voltage conversion module 40; the voltage conversion module 40 is configured to output a first voltage signal to the power supply terminal VDD of the first controller 50 according to the high-voltage AC signal; the input terminal of the first controller 50 is electrically connected to the motor M, and the control output terminal CO of the first controller 50 is electrically connected to the voltage conversion module 40; the voltage conversion module 40 is also electrically connected to the motor controller 10 and the power module 20; the first controller 50 is configured to obtain the phase voltage frequency of the motor M and output a control signal to the voltage conversion module 40 according to the phase voltage frequency M; the voltage conversion module 40 is also configured to control the working states of the power module 20 and the motor controller 10 according to the protection control signal.

[0039] Specifically, the motor controller 10 is integrated with a control system for controlling the operation of the motor M. The control system can be one of a sine pulse width modulation (SPWM) control system, a voltage space vector (SVPWM) control system, and a vector control (VC) system. It can output drive control signals to the power module based on feedback information such as the target speed, motor position, and actual speed of the motor, and can control the reliable operation of the motor.

[0040] The power module 20 can output drive signals to the motor according to the drive control signals provided by the motor controller 10. Exemplarily, the power module 20 can include a full-bridge drive circuit composed of six transistors. The first transistor Q1, the third transistor Q3, and the fifth transistor Q5 are respectively the three upper bridge arms of the full-bridge drive circuit, and the second transistor Q2, the fourth transistor Q4, and the sixth transistor Q6 are respectively the three lower bridge arms of the full-bridge drive circuit. The first high-side drive chip H1, the second high-side drive chip H2, and the third high-side drive chip H3 of the motor controller 10 are respectively electrically connected to the gates of the first transistor Q1, the third transistor Q3, and the fifth transistor Q5. The first low-side drive chip L1, the second low-side drive chip L2, and the third low-side drive chip L3 of the motor controller 10 are respectively electrically connected to the second transistor Q2, the fourth transistor Q4, and the sixth transistor Q6, and can respectively control the conduction or cutoff of each transistor. The three-phase full-bridge drive circuit is electrically connected to the DC power supply E0 to receive a DC voltage signal, and a bus capacitor C1 is connected between the positive and negative terminals where the three-phase full-bridge drive circuit is electrically connected to the DC power supply E0. The three output nodes of the three-phase full-bridge drive circuit are respectively electrically connected to the three-phase stator windings U, V, and W of the motor M. The three-phase stator windings U, V, and W of the motor M can be connected in a star connection or a delta connection. In this way, the motor controller 10 controls the conduction and cutoff of each transistor at a certain frequency, so that the power module 20 can output drive current to the three-phase stator windings of the motor M according to the DC voltage signal provided by the DC power supply E0, thereby controlling the rotation of the motor M.

[0041] The isolation and transmission module 30 can obtain electrical energy directly from the three-phase stator winding of the motor M by means of high-voltage power extraction. Exemplarily, the isolation and transmission module 30 is electrically connected to at least one phase of the three-phase stator winding of the motor M and is configured to obtain the high-voltage AC signal of at least one phase of the motor M. That is, the isolation and transmission module 30 obtains single-phase high-voltage alternating current, two-phase high-voltage alternating current or three-phase high-voltage alternating current. Specifically, the acquisition method can be selected according to actual design requirements. In the embodiment of the present invention, the isolation and transmission module 30 obtaining two-phase high-voltage alternating current is shown exemplarily. After obtaining the high-voltage AC signal, the high-voltage AC signal can be isolated and transmitted to the voltage conversion module 40, which can realize the electrical isolation between the voltage conversion module 40 and the motor M, ensuring that in the case of abnormal high voltage of the motor M, the voltage conversion module 40 and the subsequent circuits (such as the first controller 50, the motor controller 10, and the power module 20) are not affected, and improving the overall safety of the system. Exemplarily, the isolation and transmission module 30 can include at least one of an optocoupler chip, a magnetic coupler chip, and a digital isolation chip, which can ensure the reliability of high-voltage AC signal transmission and the safety of personnel and equipment, enhance the fault isolation ability and overall safety of the system, and ensure that the motor M and the power module 20 can be effectively protected from damage in case of an abnormality.

[0042] The voltage conversion module 40 can rectify and step down the high-voltage AC signal provided by the isolation and transmission module 30 to generate a DC low-voltage signal (i.e., the first voltage signal), and the first voltage signal can be provided to the power supply terminal VDD of the first controller 50 to provide a working voltage for the first controller 50, so that the first controller 50 can work normally.

[0043] The first controller 50 is electrically connected to the motor M to obtain the phase voltage frequency of the motor M, and can determine the rotation speed of the motor M according to the phase voltage frequency of the motor M. Accordingly, the first controller 50 can output a protection control signal to the voltage conversion module 40 according to the phase voltage frequency, so that the voltage conversion module 40 outputs corresponding protection drive signals to the motor controller 10 and the power module 20 according to the protection control signal to control the working states of the power module 20 and the motor controller 10, so as to be able to control the power module 20 to quickly perform a short-circuit protection action when the rotation speed of the motor M is too high to protect the motor controller 10 and the power module 20 from being reversely broken down. Among them, the first controller 50 can be a single-chip microcomputer with data processing capabilities. In this way, the system uses a first controller with a lower cost and independent of the motor controller for autonomous control, and the first controller 50 is powered by the high-voltage electricity at the motor end, and there will be no situation where the low-voltage side power supply cannot control the execution of short-circuit protection due to power failure, improving the reliability of motor protection, and avoiding complex software condition judgment and control processes by the motor controller, reducing the complexity of system implementation, simplifying the software condition judgment and control processes, reducing the overall cost, and improving the performance-price ratio and market competitiveness of the protection system.

[0044] It can be understood that when the motor is not overspeed, the power module 20 outputs a high-voltage AC drive signal to drive the motor M to rotate. At this time, the high-voltage alternating current obtained by the isolation transmission module 30 is the high-voltage alternating current output from the power module 20 to the motor M. Therefore, after the voltage conversion module 20 converts the voltage of the high-voltage alternating current, it can output a first voltage signal to the first controller 50 to supply power to the first controller. When the motor M is overspeed and the power module 20 is controlled to enter the three-phase short-circuit protection mode, the high-voltage alternating current obtained by the isolation transmission module 30 is a large back electromotive force generated by the motor M. At this time, the voltage conversion module 20 can also convert the voltage of the high-voltage alternating current and output a first voltage signal to supply power to the first controller 50, which can realize reliable power supply to the first controller 50 on the low-voltage side, and thus can reliably control the power module 20 to perform the three-phase short-circuit protection action, realizing reliable protection of the motor controller 10 and the power module 20.

[0045] The short-circuit protection control system of the motor provided by the embodiment of the present invention can isolate the voltage conversion module from the motor by configuring the isolation transmission module to obtain the high-voltage AC signal generated by the motor and isolate and transmit the high-voltage AC signal to the voltage conversion module, ensuring that the voltage conversion module and the subsequent circuit are not affected under abnormal high voltage conditions of the motor, improving the overall safety of the system. By configuring the voltage conversion module to output a first voltage signal to the power supply terminal of the first controller according to the high-voltage AC signal, it is not necessary to separately set a power supply for the first controller, which is beneficial to cost reduction, and reliable power supply to the first controller can be achieved both when the motor speed is normal and overspeed, and the power module can be reliably controlled to perform the three-phase short-circuit protection action, realizing reliable protection of the motor controller and the power module. In addition, by configuring the first controller to obtain the phase voltage frequency of the motor and output a protection control signal to the voltage conversion module according to the phase voltage frequency, and enabling the voltage conversion module to control the working states of the power module and the motor controller according to the protection control signal, the power module can be controlled to perform the short-circuit protection action to protect the motor controller and the power module from being reversely broken down when the motor speed is too high, realizing fast response and effective protection of the motor control and the power module protection action. And through the independent first controller independent of the motor controller for autonomous control, the complex software condition judgment and control process of the motor controller are avoided, the complexity of system implementation is reduced, the software condition judgment and control process are simplified, the overall cost is reduced, and the performance-price ratio and market competitiveness of the protection system are improved.

[0046] Optionally, the first controller 50 is electrically connected to at least two phases of the three-phase stator windings of the motor M; the first controller 50 is further configured to obtain the phase voltage signal of the motor M and obtain the phase voltage frequency according to the phase voltage signal.

[0047] Specifically, a two-phase voltage frequency detection module can be integrated in the first controller 50. The two-phase voltage frequency detection module can be electrically connected to the two-phase stator windings of the motor M to detect the two-phase voltage or three-phase voltage of the motor M, so as to determine the phase voltage frequency according to the two-phase voltage therein. Alternatively, a three-phase voltage frequency detection module can be integrated in the first controller 50. The three-phase voltage frequency detection module is electrically connected to the three-phase stator windings of the motor M and can determine the phase voltage frequency according to the three-phase voltage. The two-phase voltage frequency detection module and the three-phase voltage frequency detection module can be detection modules with ADC function, which can realize the rapid acquisition of the phase voltage signal by means of resistance voltage division, and can obtain the phase voltage frequency through the collected voltage signal, with the characteristics of high precision and fast response. It can accurately capture the abnormal change of the motor speed and can immediately trigger the subsequent protection action when the speed is too high.

[0048] Optionally, the first controller 10 is further configured to output the enable level of the protection control signal when the phase voltage frequency exceeds the frequency threshold, so that the voltage conversion module 40 controls the working state of the motor controller 10 to be the fault mode and controls the working state of the power module 20 to be the three-phase short-circuit protection mode according to the enable level of the protection control signal.

[0049] Specifically, the frequency threshold can be the phase voltage frequency value of the motor corresponding to the critical speed of overspeed. The frequency threshold can be obtained by two methods: one is the calibration method, and the frequency value of the motor voltage when the motor is overspeed is calibrated according to the actual bench test as the frequency threshold; the other is the calculation method, and the frequency value of the motor voltage when the motor is overspeed is calculated according to information such as the number of pole pairs of the motor as the frequency threshold. The first controller 50 can compare the obtained phase voltage frequency with the frequency threshold in real time. When the phase voltage frequency exceeds the frequency threshold, it indicates that the motor M is overspeed and in the runaway state. At this time, the enable level of the protection control signal can be output to the voltage conversion module 40.

[0050] When the received protection control signal is the enable level, the voltage conversion module 40 outputs the enable level of the protection drive signal to control the working state of the motor controller 10 to be the fault mode. When controlling the working state of the motor controller 10 to switch to the fault mode, the enable level of the protection drive signal can be output to the drive chip of the motor controller 10. At this time, the enable level of the protection drive signal can be output to any one or more of the three high-side drive chips and the three low-side drive chips. The figure exemplarily shows the situation of outputting the enable level of the protection control drive signal to the three low-side drive chips. Then, after the drive chip receives the enable level of the protection drive signal, the motor controller 10 controls each drive chip to be in the fault mode, so that each drive chip stops outputting the drive control signal to the power module 20, and thus each transistor in the power module 20 is turned off.

[0051] In addition, when controlling the working state of the motor controller 10 to be the fault mode, the voltage conversion module 40 can also drive the working state of the power module to be the three-phase short-circuit protection mode by enabling the level of the protection drive signal. Exemplarily, in one embodiment, the voltage conversion module 40 can be electrically connected to the gates of the three transistors (i.e., the second transistor Q2, the fourth transistor Q4, and the sixth transistor Q6) of the lower bridge arm in the power module 20. Then, when the received protection control signal is the enabling level, the three transistors of the lower bridge arm can be controlled to conduct. Alternatively, in another embodiment, the voltage conversion module 40 can be electrically connected to the gates of the three transistors (i.e., the first transistor Q1, the third transistor Q3, and the fifth transistor Q5) of the upper bridge arm in the power module 20. When the received protection control signal is the enabling level, the three transistors of the upper bridge arm can be controlled to conduct. Figure 1 Only the case where the voltage conversion module 40 is electrically connected to the gates of the three transistors of the lower bridge arm in the power module 20 is exemplarily shown. Without special instructions, the following embodiments will be explained by taking the electrical connection between the voltage conversion module 40 and the gates of the three transistors of the lower bridge arm in the power module 20 as an example. In this way, since the motor controller 10 enters the fault mode and no longer controls the conduction of the transistors in the power module 20, only the three transistors of the lower bridge arm in the power module 20 conduct at this time, realizing the short-circuit connection of the three-phase stator windings of the motor M. The stator windings of the motor M can form a loop with the transistors on the conducting side arm of the bridge, so that the back electromotive force energy generated by the motor is dissipated by heating through the stator windings, which can prevent the back electromotive force generated after the switch-off of the transistor at high speed in the motor controller from causing irreversible damage such as breakdown to components such as the bus capacitor in the motor controller 10, and generate a certain braking torque, which is beneficial to the rapid reduction of the speed of the motor M.

[0052] Among them, when the voltage conversion module 40 outputs a signal to the drive chip of the motor controller 10, if the output pins of each drive chip are in a fault state such as power-off and other failures, then there is no output action at the output pins of each drive chip at this time, and the transistors in the power module 20 cannot be controlled to conduct either. The enabling level of the protection drive signal output by the voltage conversion module 40 will directly drive the three transistors of the lower bridge arm to conduct, so that the power module 20 enters the three-phase short-circuit protection mode. It can ensure that when the power module 20 enters the three-phase short-circuit protection mode of the lower three bridges, the three transistors of the upper three bridges are in the off state.

[0053] Exemplarily, when the phase voltage frequency is less than or equal to the frequency threshold, it indicates that the motor M is not overspeed. At this time, a non-enabling level of the protection control signal can be output to the voltage conversion module 40. At this time, the voltage conversion module 40 may not output a protection drive signal to the power module and the motor controller 10, without interfering with the operation of the motor controller 10 and the power module 20, and ensuring the normal operating state of the motor M.

[0054] Optionally, Figure 2 is a schematic structural diagram of another short-circuit protection control system for a motor provided by an embodiment of the present invention. As Figure 2 shown, the voltage conversion module 40 includes a rectification module 41 and a DCDC module 42; the rectification module 41 is electrically connected between the isolation transmission module 30 and the DCDC module 42; the rectification module 41 is used to output a high-voltage DC signal to the DCDC module 42 according to the high-voltage AC signal; the DCDC module 42 is also electrically connected to the power supply terminal VDD and the control output terminal CO of the first controller 50, and further, the DCDC module 42 is also electrically connected to the motor controller 10 and the power module 20; the DCDC module 42 is used to output a first voltage signal to the power supply terminal VDD of the first controller 10 according to the high-voltage DC signal; and the DCDC module 42 is further used to control the operating states of the power module 20 and the motor controller 10 according to the protection control signal provided by the first controller 10.

[0055] Specifically, the rectification module 41 can rectify the high-voltage AC signal into a high-voltage DC signal, and the DCDC module 42 can step down the high-voltage DC signal to generate a low-voltage first voltage signal, which can supply power to the first controller 50, so that there is no need to additionally set a power supply, which is beneficial to reducing costs.

[0056] The DCDC module 42 can also, when the received protection control signal is at an enabling level, generate an enabling level (such as a low level) required by the transistors in the power module 20 from the high-voltage AC signal provided by the isolation rectification module 41, be able to control the motor controller 10 to enter a fault mode, and control the corresponding transistors to conduct so that the power module 20 enters a three-phase short-circuit protection mode. The DCDC module 42 is also configured to provide a certain energy storage function to ensure that after the power module 20 enters the three-phase short-circuit protection mode, it can stably remain in the three-phase short-circuit protection mode for a certain period of time. This time can be designed as the time when the junction temperature of the power module 20 is over-temperature in the three-phase short-circuit protection mode under conventional cooling conditions.

[0057] Meanwhile, if the output pin of the drive chip in the motor controller 10 has failed before the DCDC module 42 outputs the protection drive signal, the protection drive signal output by the DCDC module 42 will directly cause the power module 20 to enter the three-phase short-circuit protection mode.

[0058] Optionally, referring to Figure 2, the voltage conversion module 40 further includes a transformer 43; the transformer 43 is electrically connected between the isolation transmission module 30 and the rectification module 41. In this way, before rectifying the high-voltage AC signal, the high-voltage AC signal can be stepped down by the transformer 43 first, which can reduce the voltage withstand requirements of the rectification module 42 and the DCDC module, and is beneficial to cost reduction.

[0059] Optionally, referring to Figure 2 , the voltage conversion module 40 further includes a voltage regulation module 44; the voltage regulation module 44 is electrically connected between the rectification module 41 and the DCDC module 42. In this way, the DC voltage signal provided to the DCDC module 42 can be regulated, avoiding inaccurate voltage conversion of the DCDC module caused by the ripple voltage, and avoiding interference with the voltage output of the DCDC module 42.

[0060] Based on the same inventive concept, an embodiment of the present invention further provides a short-circuit protection control method for a motor, which is executed by a first controller in the short-circuit protection control system for a motor provided by any embodiment of the present invention. Figure 3 is a flowchart of a short-circuit protection control method for a motor provided by an embodiment of the present invention, as Figure 3 shown, the short-circuit protection control method for the motor includes:

[0061] S110. Obtain the phase voltage signal of the motor.

[0062] S120. Obtain the phase voltage frequency according to the phase voltage signal.

[0063] S130. When the phase voltage frequency is greater than the frequency threshold, output the enable level of the protection control signal, so that the voltage conversion module controls the motor controller to enter the fault mode according to the enable level of the protection control signal, and controls the power module to enter the short-circuit protection mode.

[0064] The short-circuit protection control method for a motor provided by an embodiment of the present invention is independently controlled by a first controller independent of the motor controller, and the motor speed is detected through the phase voltage frequency, which can quickly respond to the short-circuit protection actions of the motor control and the power module when the motor overspeed, avoiding complex software condition judgment and control processes of the motor controller, and realizing effective protection of the motor control and the power module.

[0065] Based on the same inventive concept, an embodiment of the present invention further provides a vehicle, including: a motor and the short-circuit protection control system of the motor provided in any embodiment of the present invention. Therefore, the vehicle provided by the embodiment of the present invention includes the technical features of the short-circuit protection control system of the motor provided in any embodiment of the present invention, and can achieve the beneficial effects of the short-circuit protection control system of the motor provided in any embodiment of the present invention. For the same parts, reference may be made to the description of the short-circuit protection control system of the motor provided in the embodiment of the present invention above, and details will not be repeated here.

[0066] It should be understood that various forms of the processes shown above can be used, steps can be reordered, added or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially or in a different order, as long as the desired results of the technical solution of the present invention can be achieved. There is no limitation herein.

[0067] The above specific embodiments do not limit the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A short-circuit protection control system for a motor, characterized in that: include: A motor controller, a power module, an isolation transmission module, a voltage conversion module and a first controller; The power module is electrically connected to the motor controller and the motor respectively; The motor controller is configured to control the power module to output a driving signal to the motor; The isolation transmission module is electrically connected to the motor and the voltage conversion module respectively, and the voltage conversion module is also electrically connected to the power supply end of the first controller; the isolation transmission module is configured to obtain the high-voltage AC signal generated by the motor, and isolate and transmit the high-voltage AC signal to the voltage conversion module; the voltage conversion module is configured to output a first voltage signal to the power supply end of the first controller according to the high-voltage AC signal; The input end of the first controller is electrically connected to the motor, and the control output end of the first controller is electrically connected to the voltage conversion module; the voltage conversion module is also electrically connected to the motor controller and the power module; The first controller is configured to obtain a phase voltage frequency of the motor, and output a protection control signal to the voltage conversion module according to the phase voltage frequency; The voltage conversion module is further configured to control the working states of the power module and the motor controller according to the protection control signal.

2. The short-circuit protection control system of the motor according to claim 1, characterized in that: The voltage conversion module includes a rectifier module and a DCDC module; The rectifier module is electrically connected between the isolation transmission module and the DCDC module; the rectifier module is used to output a high-voltage DC signal to the DCDC module according to the high-voltage AC signal; The DCDC module is also electrically connected to the power supply terminal and the control output terminal of the first controller, and the DCDC module is also electrically connected to the motor controller and the power module; The DCDC module is used to output a first voltage signal to the power supply end of the first controller according to the high-voltage DC signal; and the DCDC module is also used to control the working state of the power module and the motor controller according to the protection control signal provided by the first controller.

3. The short-circuit protection control system of the motor according to claim 2, characterized in that: The voltage conversion module also includes a transformer; The transformer is electrically connected between the isolation transmission module and the rectification module.

4. The short-circuit protection control system of the motor according to claim 2, characterized in that: The voltage conversion module also includes a voltage stabilization module; The voltage stabilizing module is electrically connected between the rectifying module and the DCDC module.

5. The short-circuit protection control system of the motor according to claim 1, characterized in that: The isolated transmission module is electrically connected to at least one phase of the three-phase stator winding of the motor, and is configured to obtain a high-voltage AC signal of at least one phase of the motor.

6. The short-circuit protection control system of the motor according to claim 1, characterized in that: The first controller is electrically connected to at least two phases of the three-phase stator winding of the motor; The first controller is further configured to obtain a phase voltage signal of the motor, and obtain the phase voltage frequency according to the phase voltage signal.

7. The short-circuit protection control system of the motor according to claim 1, characterized in that: The first controller is also configured to output the enable level of the protection control signal when the phase voltage frequency exceeds a frequency threshold, so that the voltage conversion module controls the working state of the motor controller to fault mode control according to the enable level of the protection control signal, and controls the working state of the power module to three-phase short-circuit protection mode.

8. The short-circuit protection control system of the motor according to claim 1, characterized in that: The isolation transmission module includes at least one of an optical coupling chip, a magnetic coupling chip and a digital isolation chip.

9. A short-circuit protection control method for a motor, executed by a first controller in a short-circuit protection control system for a motor according to any one of claims 1 to 8, characterized in that: include: Acquiring a phase voltage signal of the motor; Acquiring a phase voltage frequency according to the phase voltage signal; When the phase voltage frequency is greater than the frequency threshold, the enable level of the protection control signal is output, so that the voltage conversion module controls the motor controller to enter the fault mode according to the enable level of the protection control signal, and controls the power module to enter the short-circuit protection mode.

10. A vehicle, characterized in that: include: A motor and a short-circuit protection control system for the motor as claimed in any one of claims 1 to 8.

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