Motor controller software overcurrent control method and device and motor

Abstract

The application provides a motor controller software overcurrent control method, device and motor. The control method comprises the following steps: when it is determined that the motor is in a non-stable state, the phase current I of the motor at the current moment is collected m , and a corresponding overcurrent region level value is obtained; the initial switching frequency of the motor is adjusted based on the overcurrent region level value; the overcurrent region level value of the phase current at the current moment is adjusted based on the phase current at the current moment and the phase current at the previous moment, and the switching frequency is adjusted correspondingly; the corresponding current loop parameter and speed loop parameter are obtained based on the adjusted switching frequency, and closed-loop control of the motor is realized. The motor controller software overcurrent control method can effectively eliminate the overcurrent problem of the driving motor, especially in the working conditions of rapid acceleration, rapid deceleration and rapid motor speed change, the overcurrent fault caused by current control overshoot is avoided, and the driving and riding experience of the customer is affected.

Description

Technical Field

[0001] This invention relates to the field of motor control, and more specifically, to a method, apparatus, and motor for overcurrent control of motor controller software. Background Technology

[0002] Internationally, a dual protection mechanism of software and hardware overcurrent protection is commonly used to address motor overcurrent issues. Typically, to protect the drive system hardware, the electric vehicle motor controller collects the three-phase current of the motor and compares it with a preset hardware protection current value. If the motor's three-phase current is less than the hardware protection current value, the vehicle operates normally; if it exceeds the hardware protection current value, the IGBT (Insulated Gate Bipolar Transistor) is shut down, and the drive system stops working. For the drive motor, software overcurrent protection is generally recoverable. If this measure cannot control the motor's phase current within a safe range, the hardware overcurrent protection mechanism will be triggered. However, hardware overcurrent fault handling measures are generally unrecoverable; therefore, it is necessary to improve the reliability of the software overcurrent protection mechanism.

[0003] Currently, for handling software overcurrent faults in electric vehicle drive motors, major domestic and international OEMs generally adopt the "zero torque control" method. This involves reducing the motor's phase current rapidly by outputting zero torque after a fault occurs. Once the fault is resolved, the motor's output torque returns to normal. However, under conditions of rapid acceleration, deceleration, and rapid changes in motor speed, this can lead to current control overshoot and easily cause motor phase current overcurrent faults. When an overcurrent fault occurs, it not only severely impacts the driving experience but also poses serious safety hazards. While this method can eliminate drive motor overcurrent problems, the troubleshooting process causes a sudden interruption of vehicle power, severely disrupting the driving experience for passengers. Summary of the Invention

[0004] This invention addresses the technical problems existing in the prior art by providing a motor controller software overcurrent control method, device, and motor.

[0005] According to a first aspect of the present invention, a motor controller software overcurrent control method is provided, comprising:

[0006] Feedback torque T calculated in real time by the motor controller e The current operating state of the motor is determined by the torque loading slope K.

[0007] When the motor is currently operating in an unstable state, the current phase current I of the motor at the current moment is collected. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent area level value;

[0008] Based on the overcurrent region level value, the initial switching frequency of the motor is adjusted to a first switching frequency corresponding to the overcurrent region level value;

[0009] Based on the current phase current of the motor and the phase current of the previous moment, the overcurrent region level value of the current phase current is adjusted, and the first switching frequency is adjusted accordingly to obtain the adjusted second switching frequency.

[0010] Based on the second switching frequency, the corresponding current loop parameters and speed loop parameters are obtained to achieve closed-loop control of the motor.

[0011] Based on the above technical solution, the present invention can also be improved as follows.

[0012] Optionally, the feedback torque T based on the real-time calculation of the motor controller... e Based on the torque loading slope K, the current operating state of the motor is determined, including:

[0013] Obtain the feedback torque T calculated in real time by the motor controller. e And obtain the motor feedback torque and load it to 0.9*T max The coefficient of change of motor torque, K, T max This represents the peak torque of the motor.

[0014] When the coefficient of change of motor torque K is greater than the rate of change of throttle pedal opening P under stall conditions r0 And the motor feedback torque T e Greater than 0.9*T max When this occurs, the motor is determined to be in a stalled state, which is an unstable state.

[0015] Wherein, the feedback torque T e The motor output torque is estimated in real time by the motor controller, and the motor feedback torque is applied up to 0.9*T. max The coefficient of change of motor torque K is based on the rate of change of throttle pedal opening P fed back by the vehicle controller. r Determine the rate of change P of the accelerator pedal opening under motor stall conditions. r0 Obtained through actual calibration of the entire vehicle.

[0016] Optionally, when the motor is currently in an unstable operating state, the current phase current I of the motor at the current moment is collected. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent region level values ​​include:

[0017] When the motor is currently operating in an unstable state, the current phase current I of the motor at the current moment is collected. m According to the current phase current I at the current momentm The range of current intervals that the phase current I falls into at the current moment is used to determine the current range of the phase current I at the current moment. m The corresponding overcurrent region level value N.

[0018] Optionally, based on the current phase current I at the current moment m The range of current intervals that the phase current I falls into at the current moment is used to determine the current range of the phase current I at the current moment. m The corresponding overcurrent region level value N includes:

[0019] When 80%*I max >I m ≥50%*I max At that time, the phase current I m The corresponding overcurrent zone level value N = 1;

[0020] When I max >I m ≥80%*I max At that time, the phase current I m The corresponding overcurrent zone level value N = 2;

[0021] When I m ≥I max At that time, the phase current I m The corresponding overcurrent region level value N = 3, the I max The threshold value for the three-stage overcurrent of the motor phase current is set.

[0022] Optionally, based on the overcurrent region level value, adjusting the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value includes:

[0023] When the current phase current I at the current moment m When the corresponding overcurrent region level value N=1, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K1;

[0024] When the current phase current I at the current moment m When the corresponding overcurrent region level value N=2, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K2;

[0025] When the current phase current I at the current moment m When the corresponding overcurrent region level value N=3, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K3;

[0026] The initial switching frequency K0 of the motor is the switching frequency of the vehicle during steady-state operation, which is obtained by calibration on the motor test bench according to the motor's NVH and efficiency at different speed ranges.

[0027] Optionally, the step of adjusting the overcurrent region level value of the current phase current based on the current phase current of the motor and the phase current of the previous moment, and correspondingly adjusting the first switching frequency to obtain the adjusted second switching frequency, includes:

[0028] Collect the phase current I1 of the motor at the current time t1 and the phase current I0 at the previous time t0, and calculate the difference current ΔI = I1 - I0;

[0029] If ΔI > 0.1I0, then the overcurrent region level N of the phase current at the current moment will be increased by one level.

[0030] If ΔI≤0.1I0, then the overcurrent region level N of the phase current at the current moment will be lowered by one level.

[0031] The adjusted second switching frequency is obtained based on the adjusted overcurrent region level value of the phase current at the current moment.

[0032] Optionally, the current loop parameter K cp and K ci The value is determined based on the second frequency, and the current loop parameter K... cp and K ci satisfy:

[0033]

[0034] Where L is the inductance parameter of the motor and R is the resistance of the motor windings, the relevant parameters are obtained through bench calibration;

[0035] By setting the current loop stabilization time t s The current loop parameters are tuned, and the current loop stabilization time t is specified. s for:

[0036]

[0037] The speed loop parameter K is determined based on the second switching frequency. sp and K si The values ​​are selected to make the motor speed tend to stabilize over a preset time t3.

[0038] Optionally, the feedback torque T based on the real-time calculation of the motor controller... e Based on the torque loading slope K, the current operating state of the motor is determined, followed by:

[0039] When the motor is in a stable operating state, the corresponding current loop parameters and speed loop parameters are obtained based on the motor's initial switching frequency, thereby achieving closed-loop control of the motor.

[0040] According to a third aspect of the present invention, a motor controller software overcurrent control device is provided, comprising:

[0041] The judgment module is used to determine the feedback torque T based on the real-time calculation of the motor controller. e The current operating state of the motor is determined by the torque loading slope K.

[0042] The first acquisition module is used to acquire the phase current I of the motor at the current moment when the motor is in an unstable operating state. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent area level value;

[0043] The first adjustment module is used to adjust the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value based on the overcurrent region level value.

[0044] The second adjustment module is used to adjust the overcurrent region level value of the phase current at the current moment based on the phase current of the motor at the current moment and the phase current at the previous moment, and adjust the first switching frequency accordingly to obtain the adjusted second switching frequency.

[0045] The second acquisition module is used to acquire the corresponding current loop parameters and speed loop parameters based on the second switching frequency;

[0046] The control module is used to implement closed-loop control of the motor based on current loop parameters and speed loop parameters.

[0047] According to a third aspect of the present invention, an electric motor is provided, including a motor controller software overcurrent control device, the motor controller software overcurrent control device being used to execute the motor controller software overcurrent control method.

[0048] According to a third aspect of the present invention, an electronic device is provided, including a memory and a processor, wherein the processor is configured to implement the steps of a motor controller software overcurrent control method when executing a computer management program stored in the memory.

[0049] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer management class program is stored, wherein the computer management class program, when executed by a processor, implements the steps of a motor controller software overcurrent control method.

[0050] This invention provides a motor controller software overcurrent control method, device, and motor. When the motor is determined to be in an unstable state, the method acquires the current phase current Im of the motor at the current moment and obtains the corresponding overcurrent region level value. Based on the overcurrent region level value, the initial switching frequency of the motor is adjusted. Based on the current phase current and the phase current at the previous moment, the overcurrent region level value of the current phase current is adjusted, and the switching frequency is adjusted accordingly. Based on the adjusted switching frequency, the corresponding current loop parameters and speed loop parameters are obtained to achieve closed-loop control of the motor. This invention proposes a motor controller software overcurrent control method that continuously adjusts the switching frequency, as well as the corresponding current loop parameters and speed loop parameters, based on the real-time phase current of the motor to perform software overcurrent control of the motor. This effectively eliminates the overcurrent problem of the drive motor, especially under conditions of rapid acceleration, rapid deceleration of the vehicle, and rapid changes in motor speed, avoiding phase current overcurrent faults caused by current control overshoot, which would affect the customer's driving experience. Attached Figure Description

[0051] Figure 1 A flowchart of a motor controller software overcurrent control method provided by the present invention;

[0052] Figure 2 A graph showing the relationship between motor time, speed, current loop parameters, and speed loop parameters;

[0053] Figure 3 This invention provides an overall flowchart of a motor controller software overcurrent control method.

[0054] Figure 4 This is a schematic diagram of a closed-loop control system for a motor controller (FOC).

[0055] Figure 5 A schematic diagram of the structure of a motor controller software overcurrent control device provided by the present invention;

[0056] Figure 6 A schematic diagram of the structure of an electric motor provided by the present invention;

[0057] Figure 7 A schematic diagram of the hardware structure of a possible electronic device provided by the present invention;

[0058] Figure 8 This is a schematic diagram of the hardware structure of a possible computer-readable storage medium provided by the present invention. Detailed Implementation

[0059] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, the technical features of the various embodiments or individual embodiments provided by the present invention can be arbitrarily combined with each other to form feasible technical solutions. Such combinations are not constrained by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0060] Based on the problems in the background technology, this invention proposes an overcurrent control method for a new energy vehicle motor controller software to solve the problems in the prior art. This method rapidly reduces the motor phase current by causing the drive motor to output zero torque after an overcurrent occurs, and the motor output torque returns to normal after the fault is resolved. While this method can eliminate the overcurrent problem in the drive motor, it causes a sudden interruption of vehicle power during fault handling, severely impacting the driving and riding experience for passengers.

[0061] Figure 1 A flowchart of a motor controller software overcurrent control method provided by the present invention is shown below. Figure 1 As shown, the control method mainly includes the following steps:

[0062] S1, based on the feedback torque T calculated in real time by the motor controller. e The current operating state of the motor is determined by the torque loading slope K.

[0063] As an example, the feedback torque T based on the real-time calculation of the motor controller e Based on the torque loading slope K, the current operating state of the motor is determined, including: obtaining the feedback torque T calculated in real time by the motor controller. e And obtain the motor feedback torque and load it to 0.9*T max The coefficient of change of motor torque, K, T max The peak torque of the motor; when the coefficient of change of the motor torque K is greater than the rate of change of the accelerator pedal opening P under stall conditions. r0 And the motor feedback torque T e Greater than 0.9*T max When this occurs, the motor is determined to be in a stalled state, which is an unstable state.

[0064] Understandably, before implementing overcurrent control on the motor controller, the current operating state of the motor should be determined. If the motor is currently operating in a stable state, overcurrent control is unnecessary. Overcurrent control is only required when the motor is operating in an unstable state.

[0065] Among them, the motor controller calculates the feedback torque T in real time. e And the real-time loading slope of the torque, when the feedback torque T e Loaded to 90% of peak torque T max At this time, obtain the torque loading slope K (hereinafter referred to as the motor torque variation coefficient). When the motor torque variation coefficient K is greater than the throttle pedal opening change rate P under stall condition... r0 And the motor feedback torque T e Greater than 0.9*T max When this occurs, the motor is determined to be in a stalled state, which is an unstable state.

[0066] Among them, the feedback torque T e The motor output torque is estimated in real time by the motor controller, and the motor feedback torque is applied up to 0.9*T. max The coefficient of change of motor torque K is based on the rate of change of throttle pedal opening P fed back by the vehicle control unit (VCU). r Determine the rate of change P of the accelerator pedal opening under motor stall conditions. r0 Obtained through actual calibration of the entire vehicle.

[0067] S2, When the motor is currently in an unstable operating state, the current phase current I of the motor is collected at the current moment. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent zone level value.

[0068] As an example, when the motor is currently in an unstable operating state, the phase current I of the motor at the current moment is collected. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent region level values ​​include: when the motor's current operating state is unstable, the current phase current I of the motor at the current moment is collected. m According to the current phase current I at the current moment m The range of current intervals that the phase current I falls into at the current moment is used to determine the current range of the phase current I at the current moment. m The corresponding overcurrent region level value N.

[0069] Wherein, according to the phase current I at the current time m The range of current intervals that the phase current I falls into at the current moment is used to determine the current range of the phase current I at the current moment. m The corresponding overcurrent region level value N includes: when 80% * I max >I m≥50%*I max At that time, the phase current I m The corresponding overcurrent region level value N = 1; when I max >I m ≥80%*I max At that time, the phase current I m The corresponding overcurrent region level value N = 2; when I m ≥I max At that time, the phase current I m The corresponding overcurrent region level value N = 3, the I max The threshold value for the three-stage overcurrent of the motor phase current is set.

[0070] Understandably, when it is determined that the motor is currently operating in an unstable state, overcurrent control is required. At this time, the current phase current I of the motor is collected. m The current phase current I of the motor m The current is compared with the current overcurrent threshold to determine the overcurrent region to which the current phase current of the motor belongs, and a corresponding level value (overcurrent region level value) is assigned to the overcurrent region.

[0071] The motor phase current overcurrent threshold was obtained through actual bench testing, comparing the real-time phase current collected by the phase current sensor with the phase current overcurrent threshold. The overcurrent region level value was determined based on the real-time phase current I collected by the current sensor. m The classification is based on a comparison with the overcurrent threshold, specifically when 80% * I max >I m ≥50%*I max Then the current phase current I of the motor m In the overcurrent region I, the corresponding overcurrent region level value N = 1; when I max >I m ≥80%*I max Then the current phase current I of the motor m In the overcurrent region П, the corresponding overcurrent region level value N = 2; when I m ≥I max Then the current phase current I of the motor m Located in the overcurrent zone Ш, the corresponding overcurrent zone level value N = 3, I max The three-level overcurrent thresholds for the motor phase current were obtained through actual bench testing. The correspondence between the overcurrent region levels corresponding to different phase current overcurrent thresholds is shown in Table 1 below.

[0072] Table 1

[0073] Phase current overcurrent threshold <![CDATA[50%*I max ]]> <![CDATA[80%*I max ]]> <![CDATA[I max ]]> Overcurrent region level value N 1 2 3

[0074] S3, based on the overcurrent region level value, adjust the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value.

[0075] As an example, adjusting the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value based on the overcurrent region level value includes: when the phase current I at the current moment... m When the corresponding overcurrent region level value N = 1, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K1; when the current phase current I at the current moment... m When the corresponding overcurrent region level value N = 2, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K2; when the current phase current I at the current moment... m When the corresponding overcurrent region level value N=3, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K3; wherein, the initial switching frequency K0 of the motor is the switching frequency during steady-state operation of the whole vehicle, which is obtained by calibration on the motor test bench according to the NVH and efficiency of the motor in different speed ranges.

[0076] It is understandable that step S2 above obtains the overcurrent region level value N of the current phase current of the motor, and adjusts the initial switching frequency of the motor according to the overcurrent region level value N of the current phase current of the motor.

[0077] The initial switching frequency of the motor is the switching frequency K0 during steady-state operation of the vehicle. This frequency is obtained through calibration on a motor test bench based on the motor's NVH and efficiency at different speed ranges. Therefore, the initial switching frequency K0 varies for different speed ranges. The speed loop PI parameter K0 corresponds to the switching frequency K0 within different speed ranges. sp0 K si0 and current loop PI parameter K cp0 K ci0 If the current phase current of the motor is in the phase current overcurrent region, the switching frequency is adjusted from the initial switching frequency to the corresponding overcurrent switching frequency. The overcurrent switching frequency is adjusted according to the overcurrent region of the phase current, specifically: if the current phase current is in phase current overcurrent region I, the switching frequency is adjusted from K0 to K1; if the current phase current is in phase current overcurrent region II, the switching frequency is adjusted from K0 to K2; if the phase current is in phase current overcurrent region III, the switching frequency is adjusted from K0 to K3. The speed loop PI parameter K... sp K si and current loop PI parameter K cp K ci It corresponds to the switching frequency of the current overcurrent region.

[0078] S4. Based on the current phase current of the motor and the phase current of the previous moment, adjust the overcurrent region level value of the current phase current and adjust the first switching frequency accordingly to obtain the adjusted second switching frequency.

[0079] As an example, the step of adjusting the overcurrent region level value of the current phase current based on the current phase current of the motor at the current moment and the phase current at the previous moment, and correspondingly adjusting the first switching frequency to obtain the adjusted second switching frequency, includes: collecting the phase current I1 at the current moment t1 and the phase current I0 at the previous moment t0, and calculating the difference current ΔI = I1 - I0; if ΔI > 0.1I0, then the overcurrent region level value N of the current phase current is increased by one level value; if ΔI ≤ 0.1I0, then the overcurrent region level value N of the current phase current is decreased by one level value; and obtaining the adjusted second switching frequency based on the adjusted overcurrent region level value of the current phase current.

[0080] It is understandable that, based on the current phase current I of the motor m Within the corresponding overcurrent region, the initial switching frequency of the motor is adjusted, and the adjusted switching frequency is called the first switching frequency. For the adjusted first switching frequency, this step further adjusts the overcurrent region level value of the current phase current based on the relationship between the current phase current and the previous phase current, and also adjusts the first switching frequency to obtain the adjusted second switching frequency.

[0081] Specifically, the phase current I1 at the current time T1 of the motor is collected and the phase current I0 at the previous time T0 is processed to obtain the difference current ΔI = I1 - I0. The difference ΔI between the phase currents at adjacent times is compared with the preset threshold. The time of phase current collection is the sampling period of the phase current sensor. The threshold is set to 10% * I0.

[0082] If ΔI > 0.1I0, the overcurrent region level N of the phase current at the current moment is increased by one level; if ΔI ≤ 0.1I0, the overcurrent region level N of the phase current at the current moment is decreased by one level; based on the adjusted overcurrent region level N of the phase current at the current moment, the adjusted second switching frequency is obtained.

[0083] For example, if the overcurrent region level of the current phase current of the motor is 2, and the current difference ΔI between the current phase current and the previous phase current is greater than 0.1I0, then the overcurrent region level of the current phase current is adjusted to 3; if the current difference ΔI between the current phase current and the previous phase current is less than 0.1I0, then the overcurrent region level of the current phase current is adjusted to 1. Based on the adjusted overcurrent region level, the switching frequency of the motor is adjusted again; this adjusted switching frequency is called the second switching frequency.

[0084] S5. Based on the second switching frequency, obtain the corresponding current loop parameters and speed loop parameters to achieve closed-loop control of the motor.

[0085] Understandably, the above steps adjust the motor's switching frequency based on the current phase current and its trend compared to the previous moment. The corresponding current loop parameters and speed loop parameters are then obtained based on the final adjusted switching frequency.

[0086] Among them, the current loop parameter K cp K ci and speed ring parameter K sp K si The values ​​are determined based on the current switching frequency (second switching frequency). Specifically, the current loop parameters are tuned to the PI parameters based on the current switching frequency K. To avoid PI control overshoot under full throttle acceleration and stall conditions, the current loop parameter K... cp and K ci Must meet:

[0087]

[0088] Where L is the inductance parameter of the motor and R is the resistance of the motor windings, the relevant parameters are obtained through bench calibration.

[0089] By setting the current loop stabilization time t s The current loop parameters are tuned, and the current loop stabilization time t is set. s for:

[0090]

[0091] Speed ​​ring parameter K sp K si The value is determined based on the switching frequency. During the value determination process, the speed loop parameter is adjusted as follows: Figure 2 The speed loop parameter K corresponding to t3 shown is shown. sp K si The motor speed tends to stabilize after a preset time t3. The speed loop parameters shown in t3 have good stability and a long speed response time. Finally, the corresponding current loop and speed loop PI parameters are obtained under different switching frequencies.

[0092] It should be noted that when the motor is determined to be in a stable state in step S1, the corresponding current loop parameters and speed loop parameters are obtained based on the initial switching frequency of the motor, thereby realizing closed-loop control of the motor.

[0093] See Figure 3The present invention provides an overall flowchart of a motor controller software overcurrent control method, which mainly includes the following steps:

[0094] (1) The motor controller calculates the feedback torque T in real time. e The magnitude and torque loading slope K are used to determine the rising slope K of the 90% peak torque of the motor feedback torque loading, and to determine the current working state of the motor.

[0095] (2) If the motor is currently in an unstable operating state, the phase current sensor collects and determines the current phase current I of the motor. m Determine the motor overcurrent value and the overcurrent region value N where the phase current is located (N takes values ​​of 0, 1, 2, and 3).

[0096] (3) When the phase current is in the phase current overcurrent region, the switching frequency is adjusted from the initial switching frequency to the overcurrent switching frequency.

[0097] (4) Collect the phase current I1 at the current time t1 and the phase current I0 at the previous time t0, perform difference processing, and at the same time determine the magnitude of the difference current ΔI=I1-I0 and the 10%*I0 phase current.

[0098] (5) If ΔI = I1 - I0 is greater than 10% * I0, then the overcurrent region level value is increased; if ΔI = I1 - I0 is less than 10% * I0, then the overcurrent region level value is decreased. After adjusting the overcurrent region level value, the switching frequency is adjusted accordingly, and the current loop parameters and speed loop parameters corresponding to the switching frequency are obtained.

[0099] (6) Based on the acquired current loop parameters and speed loop parameters, the motor is controlled in a closed loop.

[0100] See Figure 4 A system for FOC (Free-Order Control) of a motor controller, the permanent magnet synchronous motor control system mainly includes a current loop PI regulator, a speed loop PI regulator, a Park inverse converter module, an SVPWM module, an inverter module, a Clark converter module, a Park converter module, and a permanent magnet synchronous motor. The MCU (Microcontroller Unit) uses the permanent magnet synchronous motor speed reference signal n... ref The difference between the actual rotational speed n collected by the motor rotor position sensor and the actual rotational speed n is calculated, then processed by the speed loop PI, and finally processed by MTPA to obtain the quadrature and direct axis currents iq. ref and ID ref The aforementioned current loop PI regulator and speed loop PI regulator will adjust the quadrature and direct axis currents iq. * and ID * Converted into AC and DC axis voltages u q and u d Then, it is converted into u by the Park inverse transform module. β and uα Finally, the SVPWM module converts the current into switching signals to control the inverter module, which in turn controls the inverter to output alternating three-phase current, thereby controlling the permanent magnet synchronous motor. The Clark converter module converts the three-phase current into i... α and i β And converted into i through the Park transformation module. d and i q This enables closed-loop control of the current.

[0101] This invention proposes a software overcurrent control method for motor controllers. Based on the real-time phase current of the motor, the switching frequency, as well as the corresponding current loop parameters and speed loop parameters, are continuously adjusted to perform software overcurrent control on the motor. This can effectively eliminate the overcurrent problem of the drive motor, especially under conditions of rapid acceleration, rapid deceleration of the vehicle, and rapid changes in motor speed. It avoids phase current overcurrent faults caused by current control overshoot, which would affect the driving experience of customers.

[0102] See Figure 5 The present invention provides a motor controller software overcurrent control device, comprising a judgment module 501, a first acquisition module 502, a first adjustment module 503, a second adjustment module 504, a second acquisition module 505, and a control module 506, wherein:

[0103] The judgment module 501 is used to determine the feedback torque T based on the real-time calculation of the motor controller. e The current operating state of the motor is determined by the torque loading slope K.

[0104] The first acquisition module 502 is used to acquire the phase current I of the motor at the current moment when the motor is in an unstable operating state. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent area level value;

[0105] The first adjustment module 503 is used to adjust the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value based on the overcurrent region level value.

[0106] The second adjustment module 504 is used to adjust the overcurrent region level value of the phase current at the current moment based on the phase current of the motor at the current moment and the phase current at the previous moment, and adjust the first switching frequency accordingly to obtain the adjusted second switching frequency.

[0107] The second acquisition module 505 is used to acquire the corresponding current loop parameters and speed loop parameters based on the second switching frequency;

[0108] The control module 506 is used to implement closed-loop control of the motor based on current loop parameters and speed loop parameters.

[0109] It is understood that the motor controller software overcurrent control device provided by the present invention corresponds to the motor controller software overcurrent control method provided in the foregoing embodiments. The relevant technical features of the motor controller software overcurrent control device can be referred to the relevant technical features of the motor controller software overcurrent control method, and will not be repeated here.

[0110] See Figure 6 The present invention provides an electric motor, including a motor controller software overcurrent control device, which is used to execute a motor controller software overcurrent control method.

[0111] Please see Figure 7 , Figure 7 This is a schematic diagram illustrating an embodiment of the electronic device provided in this invention. For example... Figure 7 As shown, an embodiment of the present invention provides an electronic device 700, including a memory 710, a processor 720, and a computer program 711 stored in the memory 710 and executable on the processor 720. When the processor 720 executes the computer program 711, it performs the following steps: based on the feedback torque T calculated in real time by the motor controller... e The current operating state of the motor is determined by the torque loading slope K; when the current operating state of the motor is unstable, the phase current I of the motor at the current moment is collected. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent region level value is determined; based on the overcurrent region level value, the initial switching frequency of the motor is adjusted to a first switching frequency corresponding to the overcurrent region level value; based on the current phase current and the previous phase current of the motor, the overcurrent region level value of the current phase current is adjusted, and the first switching frequency is adjusted accordingly to obtain the adjusted second switching frequency; based on the second switching frequency, the corresponding current loop parameters and speed loop parameters are obtained to achieve closed-loop control of the motor.

[0112] Please see Figure 8 , Figure 8 This is a schematic diagram illustrating an embodiment of a computer-readable storage medium provided by the present invention. (See diagram below.) Figure 8 As shown, this embodiment provides a computer-readable storage medium 800, on which a computer program 811 is stored. When the computer program 811 is executed by a processor, it performs the following steps: based on the feedback torque T calculated in real time by the motor controller... e The current operating state of the motor is determined by the torque loading slope K; when the current operating state of the motor is unstable, the phase current I of the motor at the current moment is collected. m And obtain the current phase current I of the motor at the current moment. mThe corresponding overcurrent region level value is determined; based on the overcurrent region level value, the initial switching frequency of the motor is adjusted to a first switching frequency corresponding to the overcurrent region level value; based on the current phase current and the previous phase current of the motor, the overcurrent region level value of the current phase current is adjusted, and the first switching frequency is adjusted accordingly to obtain the adjusted second switching frequency; based on the second switching frequency, the corresponding current loop parameters and speed loop parameters are obtained to achieve closed-loop control of the motor.

[0113] This invention provides a motor controller software overcurrent control method, device, and motor. Based on the real-time phase current of the motor, the switching frequency, corresponding current loop parameters, and speed loop parameters are continuously adjusted to perform software overcurrent control on the motor. This addresses the shortcomings of existing technologies by ensuring the drive motor outputs zero torque after an overcurrent occurs, thus rapidly reducing the motor phase current. Once the fault is resolved, the motor output torque returns to its normal value. This effectively eliminates drive motor overcurrent problems, especially under conditions of rapid vehicle acceleration, deceleration, and rapid motor speed changes. It prevents current control overshoot from causing phase current overcurrent faults, thus avoiding impacts on the customer's driving experience.

[0114] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0115] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0116] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0117] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0118] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0119] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0120] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A software-based overcurrent control method for a motor controller, characterized in that, include: Feedback torque T calculated in real time by the motor controller e The current operating state of the motor is determined by the torque loading slope K. When the motor is currently operating in an unstable state, the current phase current I of the motor at the current moment is collected. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent area level value; Based on the overcurrent region level value, the initial switching frequency of the motor is adjusted to a first switching frequency corresponding to the overcurrent region level value; Based on the current phase current of the motor and the phase current of the previous moment, the overcurrent region level value of the current phase current is adjusted, and the first switching frequency is adjusted accordingly to obtain the adjusted second switching frequency. Based on the second switching frequency, the corresponding current loop parameters and speed loop parameters are obtained to achieve closed-loop control of the motor. The step of adjusting the overcurrent region level value of the current phase current based on the current phase current of the motor at the current moment and the phase current at the previous moment, and correspondingly adjusting the first switching frequency to obtain the adjusted second switching frequency, includes: Collect the phase current I1 of the motor at the current time t1 and the phase current I0 at the previous time t0, and calculate the difference current ΔI=I1-I0; If ΔI > 0.1I0, then the overcurrent region level N of the phase current at the current moment will be increased by one level. If ΔI≤0.1I0, then the overcurrent region level N of the phase current at the current moment will be lowered by one level. The adjusted second switching frequency is obtained based on the adjusted overcurrent region level value of the phase current at the current moment.

2. The motor controller software overcurrent control method according to claim 1, characterized in that, The determination of the motor's current operating state based on the feedback torque Te and torque loading slope K calculated in real time by the motor controller includes: Obtain the feedback torque T calculated in real time by the motor controller. e And obtain the motor feedback torque and load it to 0.9*T. max The coefficient of change of motor torque, K, T max This represents the peak torque of the motor. When the coefficient of change of motor torque K is greater than the rate of change of throttle pedal opening P under stall conditions r0 And the motor feedback torque T e Greater than 0.9*T max When this occurs, the motor is determined to be in a stalled state, which is an unstable state. Wherein, the feedback torque T e The motor output torque is estimated in real time by the motor controller, and the motor feedback torque is applied up to 0.9*T. max The coefficient of change of motor torque K is based on the rate of change of throttle pedal opening P fed back by the vehicle controller. r Determine the rate of change P of the accelerator pedal opening under motor stall conditions. r0 Obtained through actual calibration of the entire vehicle.

3. The motor controller software overcurrent control method according to claim 1, characterized in that, When the motor is currently in an unstable operating state, the current phase current Im of the motor at the current moment is collected, and the overcurrent region level value corresponding to the current phase current Im of the motor at the current moment is obtained, including: When the motor is currently operating in an unstable state, the current phase current I of the motor at the current moment is collected. m According to the current phase current I at the current moment m The range of current intervals that the phase current I falls into at the current moment is used to determine the current range of the phase current I at the current moment. m The corresponding overcurrent region level value N.

4. The motor controller software overcurrent control method according to claim 3, characterized in that, Based on the current range within which the current phase current Im falls at the current moment, the overcurrent region level value N corresponding to the current phase current Im at the current moment is determined, including: When 80%*I max >I m ≥50%*I max At that time, the phase current I m The corresponding overcurrent zone level value N=1; When I max >I m ≥80%*I max At that time, the phase current I m The corresponding overcurrent zone level value is N=2; When I m ≥I max At that time, the phase current I m The corresponding overcurrent region level value N=3, the I max The threshold value for the three-stage overcurrent of the motor phase current is set.

5. The motor controller software overcurrent control method according to claim 4, characterized in that, Based on the overcurrent region level value, adjusting the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value includes: When the current phase current I at the current moment m When the corresponding overcurrent region level value N=1, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K1; When the current phase current I at the current moment m When the corresponding overcurrent region level value N=2, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K2; When the current phase current I at the current moment m When the corresponding overcurrent region level value N=3, the initial switching frequency K0 of the motor is adjusted to the first switching frequency K3; The initial switching frequency K0 of the motor is the switching frequency during steady-state operation of the vehicle, which is obtained by calibration on the motor test bench according to the motor's NVH and efficiency at different speed ranges.

6. The motor controller software overcurrent control method according to claim 1, characterized in that, The current loop parameters Kcp and Kci are determined based on the second switching frequency, and the current loop parameters Kcp and Kci satisfy the following: ； Where L is the inductance parameter of the motor and R is the resistance of the motor windings, the relevant parameters are obtained through bench calibration; By setting the current loop stabilization time t s The current loop parameters are tuned, and the current loop stabilization time t is specified. s for: ； The speed loop parameter K is determined based on the second switching frequency. sp and K si The values ​​are selected to make the motor speed tend to stabilize over a preset time t3.

7. The motor controller software overcurrent control method according to any one of claims 1-6, characterized in that, The current operating state of the motor is determined based on the feedback torque Te and torque loading slope K calculated in real time by the motor controller, followed by: When the motor is in a stable operating state, the corresponding current loop parameters and speed loop parameters are obtained based on the motor's initial switching frequency, thereby achieving closed-loop control of the motor.

8. A motor controller software overcurrent control device, characterized in that, include: The judgment module is used to determine the feedback torque T based on the real-time calculation of the motor controller. e The current operating state of the motor is determined by the torque loading slope K. The first acquisition module is used to acquire the phase current I of the motor at the current moment when the motor is in an unstable operating state. m And obtain the current phase current I of the motor at the current moment. m The corresponding overcurrent area level value; The first adjustment module is used to adjust the initial switching frequency of the motor to a first switching frequency corresponding to the overcurrent region level value based on the overcurrent region level value. The second adjustment module is used to adjust the overcurrent region level value of the phase current at the current moment based on the phase current of the motor at the current moment and the phase current at the previous moment, and adjust the first switching frequency accordingly to obtain the adjusted second switching frequency. The second acquisition module is used to acquire the corresponding current loop parameters and speed loop parameters based on the second switching frequency; The control module is used to implement closed-loop control of the motor based on current loop parameters and speed loop parameters; The step of adjusting the overcurrent region level value of the current phase current based on the current phase current of the motor at the current moment and the phase current at the previous moment, and correspondingly adjusting the first switching frequency to obtain the adjusted second switching frequency, includes: Collect the phase current I1 of the motor at the current time t1 and the phase current I0 at the previous time t0, and calculate the difference current ΔI=I1-I0; If ΔI > 0.1I0, then the overcurrent region level N of the phase current at the current moment will be increased by one level. If ΔI≤0.1I0, then the overcurrent region level N of the phase current at the current moment will be lowered by one level. The adjusted second switching frequency is obtained based on the adjusted overcurrent region level value of the phase current at the current moment.

9. An electric motor, characterized in that, The invention includes a motor controller software overcurrent control device, which is used to execute the motor controller software overcurrent control method according to any one of claims 1-7.

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