Rapid discharging method, device, equipment and vehicle

Abstract

The invention provides a rapid discharging method, device and equipment and a vehicle, and is applied to the technical field of vehicles, whether a motor controller enters a rapid discharging mode or not is judged by responding to a received rapid discharging instruction for indicating the motor controller to enter the rapid discharging mode, and after it is judged that the motor controller enters the rapid discharging mode, according to a first discharging strategy, the motor controller enters the rapid discharging mode. According to the first discharging strategy, the direct-axis current of the motor is dynamically assigned according to the preset step length, and the quadrature-axis voltage of the motor is set to be the preset quadrature-axis voltage, so that compared with the given quadrature-axis output current, the quadrature-axis output current of the motor is dynamically assigned, and the quadrature-axis voltage of the motor is set to be the preset quadrature-axis voltage. And rapid discharging is carried out according to the first discharging strategy, so that the condition of motor rotating speed fluctuation caused by continuously adjusting the quadrature-axis voltage at the given value for stabilizing the quadrature-axis output current can be avoided, and the safety, comfort and driving feeling of the electric vehicle in the rapid power-off process are ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a rapid discharge method, device, equipment and vehicle. BACKGROUND

[0002] In a pure electric energy driving control loop of an electric vehicle, a large-capacity support capacitor is usually arranged on a high-voltage direct-current side for filtering, so as to avoid the impact of the direct-current side current pulse caused by the continuous switching of insulated gate bipolar transistors (IGBT) in the motor controller. Due to the space limitation in the motor controller and the power limitation of the discharge resistor, after the battery management system disconnects the main loop, the discharge is performed in a passive manner such as resistance, and the required discharge time is long, and the high-voltage leakage is prone to occur, which is risky.

[0003] In the prior art, in order to avoid the high-voltage capacitor discharge time being too long to cause high-voltage leakage, when the motor driving current of the electric vehicle controller is converted into a cross-axis torque current and a direct-axis excitation current through space coordinate conversion, the control is that the cross-axis output current is 0 and the direct-axis output motor allows a large enough current, that is, the electric quantity of the high-voltage capacitor can be quickly discharged when the motor is kept in a stationary state.

[0004] However, due to the interference of current sensor sampling noise, the actual value of the cross-axis output current will randomly fluctuate around the given value, at this time, the current loop proportional-integral (PI) regulator will continuously adjust the cross-axis voltage to stabilize the cross-axis output current at 0, and the cross-axis voltage is modulated by pulse width modulation (PWM) to generate a duty cycle signal, which is output to the motor by driving the inverter. Since the cross-axis voltage is related to the torque, the continuous adjustment of the cross-axis voltage, that is, the fluctuation, will cause the motor speed to fluctuate during the rapid power-down process, which affects the safety, comfort and driving experience of the electric vehicle. SUMMARY

[0005] Therefore, the present application provides a rapid discharge method, device, equipment and vehicle, which can avoid the speed fluctuation during the rapid power-down process of the high-voltage capacitor, and effectively ensure the safety, comfort and driving experience of the electric vehicle.

[0006] In order to achieve the above purpose, the present application provides the following technical solutions:

[0007] In a first aspect, the present application provides a rapid discharge method, comprising:

[0008] In response to the received rapid discharge instruction, it is judged whether to enter the rapid discharge mode, and the rapid discharge instruction is used to indicate that the motor controller enters the rapid discharge mode.

[0009] The discharge module is configured to, after determining that the quick discharge mode is entered, perform quick discharge on the high-voltage capacitor in the motor controller according to a first discharge strategy, and the first discharge strategy is to dynamically assign the direct-axis current of the motor according to a preset step length and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage.

[0010] The discharge module is configured to, after determining that the active discharge exit condition is met, exit the active discharge mode.

[0011] In a second aspect, an embodiment of the present application discloses a quick discharge device, and the device comprises:

[0012] The judgment module is configured to, in response to a received quick discharge instruction, determine whether to enter a quick discharge mode, and the quick discharge instruction is used to instruct the motor controller to enter the quick discharge mode.

[0013] The discharge module is configured to, after determining that the quick discharge mode is entered, perform quick discharge on the high-voltage capacitor in the motor controller according to a first discharge strategy, and the first discharge strategy is to dynamically assign the direct-axis current of the motor according to a preset step length and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage.

[0014] The discharge module is further configured to, after determining that the active discharge exit condition is met, exit the active discharge mode.

[0015] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory and a processor.

[0016] The memory is connected with the processor and is configured to store a program.

[0017] The processor is configured to realize the quick discharge method according to the first aspect by running the program in the memory.

[0018] In a fourth aspect, an embodiment of the present application provides a storage medium, and the storage medium stores a computer program, and the computer program is run by a processor to realize the quick discharge method according to the first aspect.

[0019] In a fifth aspect, an embodiment of the present application provides a vehicle, and the vehicle is provided with the quick discharge device according to the second aspect or the electronic device according to the third aspect.

[0020] In the quick discharging method, the device, the equipment and the vehicle, the quick discharging mode can be entered in response to the received quick discharging instruction indicating that the motor controller enters the quick discharging mode, the high-voltage capacitor in the motor controller is discharged quickly according to the first discharging strategy after it is judged that the quick discharging mode is entered, and the active discharging mode is exited after it is judged that the active discharging exit condition is met. Since the first discharging strategy is to dynamically assign the direct-axis current of the motor according to a preset step and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage, the quick discharging according to the first discharging strategy can avoid the situation that the motor speed fluctuates due to the continuous adjustment of the quadrature-axis voltage to stabilize the given quadrature-axis output current, thereby ensuring the safety, comfort and driving experience of the electric vehicle during the quick discharging process. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the provided drawings.

[0022] Figure 1 A flowchart of a quick discharging method according to an embodiment of the present application is shown in the figure.

[0023] Figure 2 A schematic diagram of the overall logic of a quick discharging method according to an embodiment of the present application is shown in the figure.

[0024] Figure 3 A schematic diagram of the change of direct-axis and quadrature-axis currents according to an embodiment of the present application is shown in the figure.

[0025] Figure 4 A schematic diagram of a quick discharging logic according to an embodiment of the present application is shown in the figure.

[0026] Figure 5 A vector topology structure diagram of a motor according to an embodiment of the present application is shown in the figure.

[0027] Figure 6 A structure schematic diagram of an electronic device according to an embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0029] The following will first introduce the technical terms involved in the present application.

[0030] Passive discharge, i.e. discharging by passive means, refers to slowly releasing residual electrical energy through resistance or other means to reduce the voltage of the capacitor without the need for active discharge or in the case of failure of active discharge. Passive discharge can occur automatically after the battery management system disconnects the main loop, but it takes a certain amount of time.

[0031] Active discharge, i.e. fast discharge, is a technology that releases residual electrical energy on the capacitor at a faster speed by the command of the controller. It usually involves the participation of the motor controller, which quickly releases electrical energy through the motor winding. The speed of active discharge is greater than that of passive discharge, which can quickly reduce the voltage of the capacitor to a safe level.

[0032] The resolver is composed of a stator and a rotor. According to the principle of electromagnetic induction, it outputs an induced potential containing the cosine and sine signals of the rotor rotation angle. Through decoding calculation, the real-time position of the motor rotor can be obtained in real time.

[0033] As mentioned earlier, in order to solve the problem of long discharge time and easy high voltage leakage when discharging by passive means such as resistance after the battery management system disconnects the main loop due to the limitation of internal space and discharge resistance power of the motor controller, the existing technology usually decouples the motor drive current into quadrature axis torque current and direct axis excitation current through space coordinate transformation when the electric vehicle controller controls the quadrature axis output current to be 0 and the direct axis output current to be a large enough current allowed by the motor to keep the motor in a stationary state, thereby quickly completing the discharge of high voltage capacitor.

[0034] However, due to the interference of current sensor sampling noise, the actual value of the quadrature axis output current will randomly fluctuate around the given value. At this time, the current loop PI regulator will continuously adjust the quadrature axis voltage to stabilize the quadrature axis output current at 0. The quadrature axis voltage is PWM modulated to generate a duty cycle signal, which drives the inverter output to the motor. Since the quadrature axis voltage is related to the torque, the continuous adjustment of the quadrature axis voltage will cause the motor speed to fluctuate during the fast power-down process, affecting the safety, comfort and driving experience of the electric vehicle.

[0035] In addition, due to the consistency problem of the motor, even if the motors of the same batch are produced, the initial angle of the motor rotary transformer position will also be different, or the rotary transformer position of the vehicle will slip during use, or the motor rotary transformer position will change after replacing the rotary transformer. When the control output current of the cross axis is 0 and the output current of the direct axis is a large enough current allowed by the motor, a part of the given large enough direct axis current will be distributed on the cross axis. Because the cross axis current is strongly related to the torque, the change of the cross axis current will cause the motor speed fluctuation during the rapid power-off process, which will affect the safety, comfort and driving experience of the electric vehicle. The size of the motor speed fluctuation is related to the size of the direct axis current and the deviation of the initial angle of the motor rotary transformer.

[0036] To solve the problem of motor speed fluctuation in the rapid discharge of the high-voltage capacitor of the motor controller in the prior art, the application provides a rapid discharge method. In response to the received rapid discharge instruction indicating that the motor controller enters the rapid discharge mode, it is judged whether to enter the rapid discharge mode. According to the first discharge strategy, the high-voltage capacitor in the motor controller is rapidly discharged, and the active discharge mode is exited after the active discharge exit condition is met. The first discharge strategy is to dynamically assign the direct axis current of the motor according to the preset step size and set the cross axis voltage of the motor to the preset cross axis voltage. Compared with the given cross axis output current in the prior art, the rapid discharge according to the first discharge strategy can avoid the situation that the motor speed fluctuation is caused by the continuous adjustment of the cross axis voltage to stabilize the cross axis output current at a given value, thereby effectively ensuring the safety, comfort and driving experience of the electric vehicle during the rapid power-off process.

[0037] In an electric vehicle, the rapid discharge of the high-voltage capacitor of the motor controller is one of the core technologies to ensure the safe and reliable operation of the high-voltage system, which covers multiple key areas such as maintenance safety, fault protection, braking energy management, start optimization and electromagnetic compatibility control. For example, in the fault protection scenario, when the motor controller detects overcurrent, overvoltage, short circuit or insulation fault, the power supply needs to be immediately cut off and the capacitor energy needs to be quickly released.

[0038] Based on the above, in an exemplary embodiment, the application provides a rapid discharge method applied to a motor controller. The motor controller is a core device in an electric vehicle that converts battery direct current into alternating current to drive the motor to run and accurately control the motor speed, torque and steering, while realizing energy recovery and system protection functions. As shown in Figure 1 The rapid discharge method includes steps S101-S103:

[0039] S101, in response to the received rapid discharge instruction, it is judged whether to enter the rapid discharge mode.

[0040] The motor controller receives the fast discharge instruction sent by the vehicle controller, and in response to the fast discharge instruction, determines whether to enter the fast discharge mode.

[0041] The fast discharge instruction is used to instruct the motor controller to enter the fast discharge mode.

[0042] Correspondingly, if the motor controller does not receive the fast discharge instruction sent by the vehicle controller, the motor controller determines not to enter the fast discharge mode.

[0043] Specifically, when the motor controller receives the fast discharge instruction sent by the vehicle controller, it determines whether the motor controller meets the active discharge entry condition. If the motor controller determines that it meets the active discharge entry condition, the motor controller determines that it enters the fast discharge mode. If the motor controller determines that it does not meet the active discharge entry condition, the motor controller determines that it does not enter the fast discharge mode.

[0044] The active discharge entry condition includes that the capacitor voltage (or called bus voltage, i.e. the voltage of the high-voltage capacitor of the motor controller) is greater than the safety voltage, and the motor controller has no fault.

[0045] More specifically, whether the motor controller has a fault can be determined by its running state. If the running state of the motor controller is normal, the motor controller has no fault. If the running state of the motor controller is abnormal, the motor controller has a fault.

[0046] In addition, the safety voltage can be determined based on the national standard. For example, the safety voltage is 60V.

[0047] Specifically, after the motor controller receives the fast discharge instruction, if the motor controller meets all the condition items in the active discharge entry condition, i.e. no fault and the capacitor voltage is greater than the safety voltage, the motor controller determines that it enters the fast discharge mode. If the motor controller cannot meet all the condition items in the active discharge entry condition, i.e. has a fault or the capacitor voltage is not greater than the safety voltage, the motor controller determines that it does not enter the fast discharge mode.

[0048] S102, after determining to enter the fast discharge mode, the motor controller performs fast discharge on the high-voltage capacitor in the motor controller according to the first discharge strategy.

[0049] After the motor controller determines to enter the fast discharge mode, it enters the fast discharge mode and performs fast discharge on the high-voltage capacitor in the motor controller according to the first discharge strategy.

[0050] The first discharge strategy is to dynamically assign the direct-axis current of the motor according to a preset step size, and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage.

[0051] Specifically, in the first discharging strategy, the direct-axis current of the motor is increased from a minimum value to a maximum value according to a preset step size.

[0052] The preset step size includes a preset time step size and a preset current step size.

[0053] More specifically, the direct-axis current of the motor is increased from a minimum value to a maximum value according to a preset step size, that is, starting from the minimum value of the direct-axis current, the direct-axis current is increased by a preset current step size every preset step size until the direct-axis current reaches its maximum value.

[0054] Exemplarily, in the first discharging strategy, the preset time step size is 1s, the preset current step size is 1A, the maximum value of the direct-axis current is 20A, and the minimum value of the direct-axis current is 1A. Starting from the value of the given direct-axis current being 1A in the first second, the value of the given direct-axis current is 2A in the second second, and so on, until the value of the given direct-axis current is 20A in the twentieth second, and the value of the direct-axis current is kept as 20A.

[0055] It should be understood that the motor controller can exit the fast discharging mode without the direct-axis current being increased to its maximum value, that is, the direct-axis current can not be increased to its maximum value.

[0056] Specifically, the preset quadrature-axis voltage is 0 in the first discharging strategy.

[0057] S103, exit the fast discharging mode after determining that the active discharging exit condition is met.

[0058] After the motor controller enters the active discharging, it determines in real time or periodically whether the active discharging exit condition is met / satisfied. If the motor controller determines that the active discharging exit condition is met, the motor controller exits the fast discharging mode. Correspondingly, if the motor controller determines that the active discharging exit condition is not met, the motor controller does not exit the fast discharging mode and continues to be in the fast discharging mode, that is, continues to discharge the high-voltage capacitor in the motor controller.

[0059] The active discharging exit condition includes that the capacitor voltage is less than or equal to a safety voltage, the motor controller fails, and a non-fast discharging instruction is received. The non-fast discharging instruction is used to instruct the motor controller to enter a working mode other than the fast discharging mode.

[0060] Specifically, when judging whether the motor controller meets the active discharge exit condition, if the motor controller meets any one of the items in the active discharge exit condition, i.e., the capacitor voltage is less than or equal to the safety voltage, the motor controller fails or receives a non-fast discharge instruction, the motor controller judges that it meets the active discharge exit condition; if the motor controller does not meet all the items in the active discharge exit condition, i.e., the capacitor voltage is greater than the safety voltage, the motor controller is not faulty and does not receive a non-fast discharge instruction, the motor controller judges that it does not meet the active discharge exit condition.

[0061] For example, the overall logic of the fast discharge method can be as shown in Figure 2 After the vehicle controller sends the fast discharge instruction, the motor controller receives the fast discharge instruction and judges whether it meets the fast discharge entry condition. If yes, the motor controller performs active discharge, i.e., enters the fast discharge mode; if no, the motor controller does not perform active discharge, i.e., does not enter the active discharge mode. After the motor controller enters the fast discharge mode, it judges whether it meets the fast discharge exit condition. If yes, it exits the active discharge; if no, the motor controller performs active discharge.

[0062] In this embodiment, the motor controller judges whether to enter the fast discharge mode in response to the received fast discharge instruction indicating that the motor controller enters the fast discharge mode. After judging to enter the fast discharge mode, the motor controller performs fast discharge on the high-voltage capacitor in the motor controller according to the first discharge strategy, and exits the active discharge mode after judging to meet the active discharge exit condition. Since the first discharge strategy is to dynamically assign the direct-axis current of the motor according to a preset step and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage, compared to a given quadrature-axis output current, fast discharge according to the first discharge strategy can avoid the situation that the motor speed fluctuates due to constant adjustment of the quadrature-axis voltage to stabilize the quadrature-axis output current, thereby ensuring the safety, comfort and driving experience of the electric vehicle during the fast discharge process.

[0063] To avoid motor speed fluctuation, in some embodiments, when the high-voltage capacitor in the motor controller is discharged according to the first discharge strategy, the motor speed is monitored. If the motor speed is not less than a first preset motor speed, the high-voltage capacitor in the motor controller is discharged according to the second discharge strategy. The second discharge strategy is to enable the switch of the motor controller and set the UVW three-phase duty cycle of the motor controller to a preset duty cycle, and the preset duty cycle has a value range of (0, 1).

[0064] Specifically, the motor controller switches the fast discharge strategy of the motor controller from the first discharge strategy to the second discharge strategy, or in other words, exits the mode of fast discharging according to the first discharge strategy and enters the mode of fast discharging according to the second discharge strategy, when it is monitored that the motor speed is the first preset motor speed or greater than the first preset motor speed.

[0065] Correspondingly, when the motor controller monitors the motor speed, if the motor speed is lower than the first preset speed, the motor controller continues to fast discharge the high-voltage capacitor in the motor controller according to the first discharge strategy.

[0066] Exemplarily, the first preset motor speed is 30 rpm, when discharging the high-voltage capacitor according to the first discharge strategy, if the motor speed fluctuates, for example, the motor speed fluctuates from 0 rpm to 30 rpm, the motor controller exits the first discharge strategy and switches to the second discharge strategy, if the motor speed does not fluctuate, the motor controller continues the first discharge strategy.

[0067] Specifically, the switch of the motor controller refers to an insulated gate bipolar transistor (IGBT) switch, and the switch enable refers to setting the IGBT switch to be normally turned on or turned off. Among them, the inverter of direct current and alternating current in the motor controller can be realized by turning on or turning off the IGBT switch.

[0068] Since the upper three-bridge short circuit is realized by controlling the IGBT switch of the upper bridge arm to be turned on / turned on, and the IGBT switch of the lower bridge arm to be turned off, the lower three-bridge short circuit is realized by controlling the IGBT switch of the lower bridge arm to be turned on, and the IGBT switch of the upper bridge arm to be turned off, when the three-phase duty ratio is 0, it is equivalent to the lower three-bridge short circuit, and when the three-phase duty ratio is 1, it is equivalent to the lower three-bridge short circuit, in the case of IGBT switch enable, setting the UVW three-phase duty ratio in the range of (0, 1) can realize the switching of the upper three-bridge short circuit and the lower three-bridge short circuit, which can protect the motor and the electrical system and reduce the excessively high motor speed.

[0069] Among them, the upper three-bridge short circuit and the lower three-bridge short circuit belong to the protection mechanism of active short circuit, which are both helpful to reduce the motor speed.

[0070] Specifically, the preset duty ratio is 0.5.

[0071] Exemplarily, as shown in Figure 3 the horizontal axis is time and the vertical axis is current, when the three-phase duty ratio of the motor controller is 0.5, the quadrature axis current presents a trend of rapidly decreasing in the initial stage and gradually increasing and tending to be stable in the subsequent stage, and the direct axis current presents a trend of more rapidly decreasing in the initial stage and tending to be stable.

[0072] In the embodiment, when the motor speed is high, i.e., is not lower than the first preset motor speed, the discharging strategy is switched from the first discharging strategy to the second discharging strategy, the three-phase duty cycle of the motor controller is adjusted to 0.5, and the IGBT switch of the motor controller is enabled. At this time, the switching frequency of the turn-on and turn-off of the IGBT switch is much higher than the motor frequency, has no influence on the motor speed, and will not cause the motor speed fluctuation. The upper and lower arms of the IGBT switch are frequently switched, and in the process of the motor speed falling back, the turn-on and turn-off loss and the dead-time effect of the IGBT switch can consume the voltage in the high-voltage capacitor, thereby playing a role of discharging the high-voltage capacitor. The capacitor discharging is performed while avoiding the motor speed fluctuation, thereby achieving the effect of reducing the motor jitter and completing the rapid discharging.

[0073] To meet the requirement of rapid discharging, when the high-voltage capacitor in the motor controller is rapidly discharged according to the second discharging strategy, the motor speed is monitored. If the motor speed is lower than the second preset motor speed, the high-voltage capacitor in the motor controller is rapidly discharged according to the first discharging strategy.

[0074] That is, if the motor speed is not lower than the second preset motor speed, the high-voltage capacitor in the motor controller is continuously rapidly discharged according to the second discharging strategy, until the motor speed is lower than the second preset motor speed, and the high-voltage capacitor in the motor controller is rapidly discharged according to the first discharging strategy.

[0075] Exemplarily, the second preset motor speed is 15 rpm, and the first preset motor speed is 30 rpm. When the high-voltage capacitor is discharged according to the first discharging strategy, if the motor speed fluctuates, for example, the motor speed fluctuates from 0 rpm to 30 rpm, the motor controller exits the first discharging strategy and switches to the second discharging strategy. When the high-voltage capacitor is discharged according to the second discharging strategy, if the motor speed decreases to 15 rpm, the motor controller exits the second discharging strategy and switches to the first discharging strategy.

[0076] The absolute value of the first preset motor speed is greater than the absolute value of the second preset motor speed.

[0077] The motor speed under the first discharging strategy is different from the motor speed under the second discharging strategy, and therefore, the absolute value of the first preset motor speed and the absolute value of the second preset motor speed are compared.

[0078] Generally, the absolute value of the first preset motor speed and the absolute value of the second preset motor speed are both greater than 0. Exemplarily, |n1|>|n2|>0, n1 is the first preset motor speed, and n2 is the second preset motor speed.

[0079] Exemplarily, the rapid discharging logic for switching between the first discharging strategy and the second discharging strategy can be as followsFigure 4 As shown, under the first discharge strategy, that is, when discharging according to the first discharge strategy, if the absolute value of the motor speed n0, |n0|, satisfies |n0|>|n1|, where |n1| is the absolute value of the first preset motor speed, then the discharge strategy of the motor controller switches to the second discharge strategy. Under the second discharge strategy, if the absolute value of the motor speed, |n0|, satisfies |n0|<|n2|, where |n2| is the absolute value of the second preset motor speed, then the discharge strategy of the motor speed switches to the first discharge strategy.

[0080] In this embodiment, when the high-voltage capacitor in the motor controller is rapidly discharged according to the second discharge strategy, if the motor speed is detected to be lower than the second preset motor speed, the system switches to the first discharge strategy to rapidly discharge the high-voltage capacitor in the motor controller. After the motor speed stabilizes, the system switches to the first discharge strategy with a higher discharge rate to discharge, which can effectively meet the requirements of rapid discharge.

[0081] To avoid motor speed fluctuations, when the system is determined to enter the fast discharge mode, if the motor speed is not lower than the third preset motor speed, the high-voltage capacitor in the motor controller will be rapidly discharged according to the second discharge strategy.

[0082] Among them, the speed of the third preset motor is higher than or equal to the speed of the first preset motor.

[0083] In this way, when the motor controller enters the fast discharge mode, it directly discharges the high-voltage capacitor in the motor controller according to the second discharge strategy to quickly stabilize the motor speed.

[0084] For example, the vector topology of the permanent-magnet synchronous motor (PMSM) in this application embodiment can be as follows: Figure 5 As shown, the system includes a speed loop, a current loop, a coordinate transformation module, a space vector pulse width modulation (SVPWM) module, and a three-phase inverter. The system input is the reference speed. Compared with the actual rotational speed w r The output is the actual speed and position of the permanent magnet synchronous motor (PMSM). Reference speed. Compared with the actual rotational speed w r The difference is compared and fed into the speed loop PI controller, which outputs a quadrature-axis current reference value. Quadrature axis current reference value With respect to the actual quadrature-axis current i qs The difference is compared and fed into the quadrature-axis current loop PI controller, which outputs a quadrature-axis voltage v. qs Direct-axis current reference value With the actual direct-axis current ids The difference is compared and fed into the direct-axis current loop PI controller, which outputs a direct-axis voltage v. ds Cross-axis voltage v qs and direct-axis voltage v ds After the coordinate transformation module, it is converted to v α and v β v α and v β The SV PWM module generates control signals to drive the three-phase inverter. The three-phase inverter outputs three-phase current i. a i b and i c This drives a permanent magnet synchronous motor. The actual speed and position signals of the permanent magnet synchronous motor are fed back to the rotor speed / position feedback module, providing feedback signals. Based on Kirchhoff's current, the three-phase motor currents are each 120° out of phase; at any given moment, the sum of the three-phase currents is 0. c It can be based on the other two phase currents, i. a with i b Figure it out.

[0085] The first discharge strategy involves setting the direct-axis current to a given value and the quadrature-axis voltage to 0, i.e., setting... Set v to a given value qs The first discharge strategy is to set the three-phase duty cycle to 0.5 (and control the IGBT switch to enable), that is, to set PWM1, PWM2, and PWM3 to 0.5.

[0086] Another embodiment of this application also proposes a fast discharge device, which includes a judgment module and a discharge module.

[0087] The judgment module is used to determine whether to enter the fast discharge mode in response to the received fast discharge command. The fast discharge command is used to instruct the motor controller to enter the fast discharge mode.

[0088] The discharge module is used to determine that after entering the fast discharge mode, to quickly discharge the high-voltage capacitor in the motor controller according to the first discharge strategy. The first discharge strategy is to dynamically assign the direct-axis current of the motor according to a preset step size and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage.

[0089] The discharge module is also used to exit the active discharge mode after determining that the active exit conditions are met.

[0090] The rapid discharging device provided by the embodiment belongs to the same application concept as the rapid discharging method provided by the above-mentioned embodiments of the application, can execute the method provided by any of the above-mentioned embodiments of the application, has the function modules and beneficial effects corresponding to the execution method. The technical details not described in detail in the embodiment can be referred to the specific processing content of the express sorting method provided by the above-mentioned embodiments of the application, which will not be described here. The functions realized by the above judgment module and discharging module can be realized by the same or different processors in the form of calling software, and the embodiments of the application are not limited.

[0091] Another embodiment of the application further provides an electronic device, referring to Figure 6 The electronic device includes a memory 600 and a processor 610.

[0092] The memory 600 is connected with the processor 610, and is configured to store programs.

[0093] The processor 610 is configured to realize the rapid discharging method disclosed in any of the above-mentioned embodiments by running the programs stored in the memory 600.

[0094] Specifically, the electronic device can further include a bus, a communication interface 620, an input device 630 and an output device 640.

[0095] The processor 610, the memory 600, the communication interface 620, the input device 630 and the output device 640 are connected with each other through the bus.

[0096] The bus can include a path for transmitting information between various components of the computer system.

[0097] The processor 610 can be a general-purpose processor, such as a general-purpose central processing unit (CPU), a microprocessor, etc., or can be an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of programs of the application. It can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a ready-to-use programmable gate array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component.

[0098] The processor 610 can include a main processor, and can further include a baseband chip, a modem, etc.

[0099] The memory 600 stores programs for implementing the technical solutions of the present application, and can also store operating systems and other key services. Specifically, the programs can include program codes, and the program codes include computer operation instructions. More specifically, the memory 600 can include a read-only memory (ROM), other types of static storage devices that can store static information and instructions, a random access memory (RAM), other types of dynamic storage devices that can store information and instructions, a disk memory, a flash memory, and the like.

[0100] The input device 630 can include devices that receive data and information input by a user, such as a keyboard, a mouse, a camera, a scanner, a light pen, a voice input device, a touch screen, a pedometer, a gravity sensor, and the like.

[0101] The output device 640 can include devices that allow information to be output to a user, such as a display screen, a printer, a speaker, and the like.

[0102] The communication interface 620 can include devices of any transceiver type for communicating with other devices or communication networks, such as an Ethernet, a radio access network (RAN), a wireless local area network (WLAN), and the like.

[0103] The processor 610 executes the programs stored in the memory 600 and calls other devices, which can be used to implement each step of any of the fast discharge methods provided by the above-described embodiments of the present application.

[0104] Those skilled in the art can understand that, Figure 6 The structure shown in the figure is only a block diagram of part of the structure related to the technical solutions of the present application, and does not constitute a limitation on the electronic device to which the technical solutions of the present application are applied. The specific electronic device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0105] The embodiments of the present application also propose a chip including a processor and a data interface, the processor reads and runs programs stored on a memory through the data interface to execute the fast discharge method introduced in any of the above-described embodiments. For specific processing processes and beneficial effects, please refer to the above-described embodiments of the fast discharge method.

[0106] In addition to the above method and device, the embodiments of the present application propose a computer program product including computer program instructions, which, when executed by a processor, cause the processor to perform the steps of the fast discharge method according to various embodiments of the present application described in the above "Exemplary Method" section of the present specification.

[0107] The computer program product can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++, or the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computing device, partly on the user's computing device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device or entirely on the remote computing device or server. The embodiments of the present application disclosed herein are only exemplary and

[0108] In addition, the embodiments of the present application also provide a storage medium, which has a computer program stored thereon, and the computer program is executed by a processor to perform the steps in the fast discharge method according to various embodiments of the present application described in the above "Exemplary Method" part of the specification.

[0109] The above describes the basic principles of the present application in combination with specific embodiments, but it should be noted that the advantages, advantages, effects and the like mentioned in the present application are only examples and are not limited, and these advantages, advantages, effects and the like cannot be considered as the various embodiments of the present application must have. In addition, the above specific details disclosed are only for the purpose of example and for the purpose of understanding, and the above details do not limit the present application to the above specific details.

[0110] The block diagrams of the devices, apparatuses, equipment, systems involved in the present application are only illustrative examples and are not intended to require or imply the connection, arrangement, configuration shown in the block diagram. As those skilled in the art will recognize, these devices, apparatuses, equipment, systems can be connected, arranged, configured in any manner. Words such as "include", "contain", "have" and the like are open-ended words, which mean "including but not limited to", and can be used interchangeably. The words "or" and "and" used herein mean the word "and / or", and can be used interchangeably unless the context clearly indicates otherwise. The word "such as" used herein means the phrase "such as but not limited to", and can be used interchangeably.

[0111] It should also be noted that in the devices, apparatuses and methods of the present application, each component or each step can be decomposed and / or recombined. These decompositions and / or recombination should be considered as equivalent solutions of the present application.

[0112] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other aspects without departing from the scope of the application. Thus, the present application is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0113] It should be understood that the limiting words "first", "second", "third", "fourth", "fifth" and "sixth" used in the embodiments description of the present application are only used for more clearly describing the technical solutions, and cannot be used to limit the protection scope of the present application.

[0114] The above description has been presented for the purpose of illustration and description. Furthermore, this description is not intended to limit the embodiments of the application to the forms disclosed herein. Although several example aspects and embodiments have been discussed above, those of ordinary skill in the art will appreciate a variety of modifications, alternatives, permutations, additions, and sub-combinations of the described aspects and embodiments.

Claims

1. A rapid discharge method, characterized in that, The method includes: In response to a received fast discharge command, determine whether to enter fast discharge mode, wherein the fast discharge command is used to instruct the motor controller to enter fast discharge mode; After determining that the fast discharge mode has been entered, the high-voltage capacitor in the motor controller is rapidly discharged according to the first discharge strategy. The first discharge strategy is to dynamically assign a value to the direct-axis current of the motor according to a preset step size and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage. Once the conditions for exiting active discharge are met, the active discharge mode will exit.

2. The rapid discharge method according to claim 1, characterized in that, The determination of whether to enter the rapid discharge mode includes: If the capacitor voltage is greater than the safe voltage and the motor controller is operating normally, then the system enters the rapid discharge mode.

3. The rapid discharge method according to claim 1, characterized in that, When rapidly discharging the high-voltage capacitor in the motor controller according to the first discharge strategy, the method further includes: Monitor motor speed; If the motor speed is not lower than the first preset motor speed, the high-voltage capacitor in the motor controller is rapidly discharged according to the second discharge strategy. The second discharge strategy is to enable the switch of the motor controller and set the UVW three-phase duty cycle of the motor controller to a preset duty cycle. The value range of the preset duty cycle is (0,1).

4. The rapid discharge method according to claim 3, characterized in that, The preset duty cycle is 0.

5.

5. The rapid discharge method according to claim 3, characterized in that, When rapidly discharging the high-voltage capacitor in the motor controller according to the second discharge strategy, the method further includes: Monitor motor speed; If the motor speed is lower than the second preset motor speed, then switch to the first discharge strategy to quickly discharge the high-voltage capacitor in the motor controller.

6. The rapid discharge method according to claim 1, characterized in that, The method further includes: When it is determined that the motor speed is not lower than the third preset motor speed when entering the fast discharge mode, the high voltage capacitor in the motor controller is rapidly discharged according to the second discharge strategy.

7. The rapid discharge method according to any one of claims 1-6, characterized in that, The step of exiting active discharge mode after determining that the active discharge exit conditions are met includes: If the capacitor voltage is less than or equal to the preset voltage, or the motor controller is in an abnormal operating state, or a non-fast discharge command is received, the active discharge mode will be exited. The non-fast discharge command is used to instruct the motor controller to enter a different operating mode than the fast discharge mode.

8. A rapid discharge device, characterized in that, The device includes: The judgment module is used to determine whether to enter the fast discharge mode in response to the received fast discharge command. The fast discharge command is used to instruct the motor controller to enter the fast discharge mode. The discharge module is used to determine that after entering the fast discharge mode, to quickly discharge the high-voltage capacitor in the motor controller according to the first discharge strategy. The first discharge strategy is to dynamically assign the direct-axis current of the motor according to a preset step size and set the quadrature-axis voltage of the motor to a preset quadrature-axis voltage. The discharge module is also used to exit the active discharge mode after determining that the active exit conditions are met.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor; The memory is connected to the processor and is used to store programs; The processor is used to implement the fast discharge method as described in any one of claims 1 to 7 by running a program in the memory.

10. A vehicle, characterized in that, The vehicle is equipped with the fast discharge device as described in claim 8, or the electronic device as described in claim 9.

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