Method and device for calibrating torque of permanent magnet synchronous motor

Abstract

The invention provides a torque calibration method and device for a permanent magnet synchronous motor, and the method comprises the steps: responding to a received target torque value outputted by an expected target permanent magnet synchronous motor when the target permanent magnet synchronous motor works through the electric energy outputted by a power supply battery, obtaining a motor rotating speed value, an electromagnetic parameter and a working current vector of the target permanent magnet synchronous motor; determining a correction coefficient value corresponding to the target permanent magnet synchronous motor by using a pre-calibrated correction function based on an output voltage value, a motor rotating speed value and a target torque value set by the power supply battery; determining a target winding inductance difference value of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference value; and based on the electromagnetic parameter, the working current vector and the target winding inductance difference value, obtaining a calibration torque value actually output by the target permanent magnet synchronous motor by using a preset torque model. By means of the method, the output precision of the torque model is improved, and then the torque output efficiency of permanent magnet synchronous motor driving is improved.

Description

Technical Field

[0001] The present application relates to the technical field of permanent magnet synchronous motor control, and in particular to a permanent magnet synchronous motor torque calibration method and calibration device. Background Art

[0002] With the popularization of electric vehicles, permanent magnet synchronous motor drive can bring superior acceleration performance, and the torque control of permanent magnet synchronous motor is very important in many applications, especially in those application scenarios that require high precision, high dynamic response and high efficiency.

[0003] At present, in the method of determining the actual torque value output by the permanent magnet synchronous motor through the torque model, the winding inductance difference used is pre-set, and the winding inductance difference remains unchanged regardless of the environment and working conditions of the permanent magnet synchronous motor, which causes the actual torque value output by the torque model to deviate, reduces the output accuracy of the torque model, and further reduces the torque output efficiency of the permanent magnet synchronous motor drive. Summary of the invention

[0004] In view of this, the purpose of the present application is to provide a permanent magnet synchronous motor torque calibration method and calibration device, which determines the correction coefficient value corresponding to the permanent magnet synchronous motor through a pre-calibrated correction function, so as to correct the preset winding inductance difference according to the target torque value expected to be output by the permanent magnet synchronous motor when working, and uses the preset torque model to obtain the calibrated torque value actually output by the permanent magnet synchronous motor, effectively quantifying the inductance change of the motor when working under various working conditions, improving the output accuracy of the torque model, and thereby improving the torque output efficiency of the permanent magnet synchronous motor drive.

[0005] The present application provides a method for calibrating the torque of a permanent magnet synchronous motor, the method comprising:

[0006] In response to receiving a target torque value that the target permanent magnet synchronous motor is expected to output when working with the electric energy output by the power supply battery, obtaining a motor speed value, electromagnetic parameters and a working current vector of the target permanent magnet synchronous motor;

[0007] Based on the output voltage value set by the power supply battery, the motor speed value and the target torque value, a correction coefficient value corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated correction function;

[0008] Determining a target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference;

[0009] Based on the electromagnetic parameters, the working current vector and the target winding inductance difference, a calibrated torque value actually output by the target permanent magnet synchronous motor is obtained using a preset torque model.

[0010] Further, the electromagnetic parameters include a preset number of pole pairs and a rotor flux value; and the step of obtaining the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor includes:

[0011] Acquire a motor speed value, an operating temperature value, and a back electromotive force of the target permanent magnet synchronous motor detected by a sensor provided in the target permanent magnet synchronous motor;

[0012] Determining a rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force;

[0013] Based on the pre-calibrated motor efficiency value of the target permanent magnet synchronous motor and the target torque value, a working current vector of the target permanent magnet synchronous motor is determined using a preset current distribution scheme.

[0014] Further, determining the rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force includes:

[0015] Based on the motor speed value and the back electromotive force, a preset flux calculation formula is used to determine the rotor flux value to be corrected of the target permanent magnet synchronous motor;

[0016] Based on the operating temperature value, the rotor flux value to be corrected is corrected to determine the rotor flux value of the target permanent magnet synchronous motor.

[0017] Furthermore, the correction coefficient value corresponding to the target permanent magnet synchronous motor is determined by using a pre-calibrated correction function based on the output voltage value set by the power supply battery, the motor speed value and the target torque value, including:

[0018] Based on the motor speed value and the target torque value, an inductance correction coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated first correction function to quantify a change in winding inductance difference under steady-state conditions;

[0019] Based on the output voltage value set by the power supply battery and the motor speed value, a dynamic switching weight coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated second correction function to quantify the change in the winding inductance difference when the operating mode is switched under different output voltage values;

[0020] The inductance correction coefficient and the dynamic switching weight coefficient are determined as correction coefficient values ​​corresponding to the target permanent magnet synchronous motor.

[0021] Furthermore, the first correction function is pre-calibrated by the following steps:

[0022] Using a test bench to control the target permanent magnet synchronous motor to start a first calibration test at a preset working voltage value and a preset temperature value;

[0023] In the first calibration test, based on a plurality of preset first value pairs including a test speed value and a first test torque value, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the first test torque value included in each of the first value pairs, so as to obtain a first measured torque value of the target permanent magnet synchronous motor;

[0024] For each of the test speed value and the first test torque value included in the first value pair, based on the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of first model torque values ​​actually output by the target permanent magnet synchronous motor;

[0025] Based on the difference between the first measured torque value and each of the first model torque values, determining the inductance correction coefficient corresponding to each of the first value pairs by adjusting parameters, so that the first model torque value and each of the first measured torque values ​​are close to being equal;

[0026] The first correction function is obtained by function fitting based on the inductance correction coefficient corresponding to each of the first value pairs.

[0027] Furthermore, the second correction function is pre-calibrated by the following steps:

[0028] Using the test bench to control the target permanent magnet synchronous motor to start a second calibration test at a second test torque value and a preset temperature value;

[0029] In the second calibration test, based on a plurality of preset second value pairs including test speed values ​​and test voltage values, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the test voltage value included in each of the second value pairs, so as to obtain a second measured torque value of the target permanent magnet synchronous motor;

[0030] For each test speed value and test voltage value included in the second value pair, based on the inductance correction coefficient and the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of second model torque values ​​actually output by the target permanent magnet synchronous motor;

[0031] Based on the difference between the second measured torque value and each of the second model torque values, determining the dynamic switching weight coefficient corresponding to each of the second value pairs by adjusting parameters, so that the second measured torque value and each of the second model torque values ​​approach equality;

[0032] Based on the dynamic switching weight coefficient corresponding to each of the second value pairs, the second correction function is obtained by function fitting.

[0033] Further, the determining the target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and the preset winding inductance difference includes:

[0034] Multiplying the inductance correction coefficient in the correction coefficient value by the preset winding inductance difference to obtain a first product result;

[0035] The first product result is multiplied by the dynamic switching weight coefficient in the correction coefficient value to obtain a second product result, and the second product result is determined as the target winding inductance difference of the target permanent magnet synchronous motor.

[0036] The embodiment of the present application further provides a permanent magnet synchronous motor torque calibration device, the calibration device comprising:

[0037] A data acquisition module, configured to obtain a motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor in response to receiving a target torque value output by the desired target permanent magnet synchronous motor when the motor is operated by using the electric energy output by the power supply battery from the host computer;

[0038] A coefficient determination module, used to determine the correction coefficient value corresponding to the target permanent magnet synchronous motor using a pre-calibrated correction function based on the output voltage value set by the power supply battery, the motor speed value and the target torque value;

[0039] an inductance determination module, configured to determine a target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference;

[0040] The torque determination module is used to obtain a calibrated torque value actually output by the target permanent magnet synchronous motor based on the electromagnetic parameters, the working current vector and the target winding inductance difference using a preset torque model.

[0041] Further, the electromagnetic parameters include a preset number of pole pairs and a rotor flux value; when the data acquisition module is used to acquire the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor, the data acquisition module is used to:

[0042] Acquire a motor speed value, an operating temperature value, and a back electromotive force of the target permanent magnet synchronous motor detected by a sensor provided in the target permanent magnet synchronous motor;

[0043] Determining a rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force;

[0044] Based on the pre-calibrated motor efficiency value of the target permanent magnet synchronous motor and the target torque value, a working current vector of the target permanent magnet synchronous motor is determined using a preset current distribution scheme.

[0045] Further, when the data acquisition module is used to determine the rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force, the data acquisition module is used to:

[0046] Based on the motor speed value and the back electromotive force, a preset flux calculation formula is used to determine the rotor flux value to be corrected of the target permanent magnet synchronous motor;

[0047] Based on the operating temperature value, the rotor flux value to be corrected is corrected to determine the rotor flux value of the target permanent magnet synchronous motor.

[0048] Further, when the coefficient determination module is used to determine the correction coefficient value corresponding to the target permanent magnet synchronous motor based on the output voltage value set by the power supply battery, the motor speed value and the target torque value using a pre-calibrated correction function, the coefficient determination module is used to:

[0049] Based on the motor speed value and the target torque value, an inductance correction coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated first correction function to quantify a change in winding inductance difference under steady-state conditions;

[0050] Based on the output voltage value set by the power supply battery and the motor speed value, a dynamic switching weight coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated second correction function to quantify the change in the winding inductance difference when the operating mode is switched under different output voltage values;

[0051] The inductance correction coefficient and the dynamic switching weight coefficient are determined as correction coefficient values ​​corresponding to the target permanent magnet synchronous motor.

[0052] Furthermore, when the coefficient determination module is used to pre-calibrate the first correction function, the coefficient determination module is used to:

[0053] Using a test bench to control the target permanent magnet synchronous motor to start a first calibration test at a preset working voltage value and a preset temperature value;

[0054] In the first calibration test, based on a plurality of preset first value pairs including a test speed value and a first test torque value, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the first test torque value included in each of the first value pairs, so as to obtain a first measured torque value of the target permanent magnet synchronous motor;

[0055] For each of the test speed value and the first test torque value included in the first value pair, based on the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of first model torque values ​​actually output by the target permanent magnet synchronous motor;

[0056] Based on the difference between the first measured torque value and each of the first model torque values, determining the inductance correction coefficient corresponding to each of the first value pairs by adjusting parameters, so that the first model torque value and each of the first measured torque values ​​are close to being equal;

[0057] The first correction function is obtained by function fitting based on the inductance correction coefficient corresponding to each of the first value pairs.

[0058] Further, when the coefficient determination module is used to pre-calibrate the second correction function, the coefficient determination module is used to:

[0059] Using the test bench to control the target permanent magnet synchronous motor to start a second calibration test at a second test torque value and a preset temperature value;

[0060] In the second calibration test, based on a plurality of preset second value pairs including test speed values ​​and test voltage values, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the test voltage value included in each of the second value pairs, so as to obtain a second measured torque value of the target permanent magnet synchronous motor;

[0061] For each test speed value and test voltage value included in the second value pair, based on the inductance correction coefficient and the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of second model torque values ​​actually output by the target permanent magnet synchronous motor;

[0062] Based on the difference between the second measured torque value and each of the second model torque values, determining the dynamic switching weight coefficient corresponding to each of the second value pairs by adjusting parameters, so that the second measured torque value and each of the second model torque values ​​approach equality;

[0063] Based on the dynamic switching weight coefficient corresponding to each of the second value pairs, the second correction function is obtained by function fitting.

[0064] Further, when the inductance determination module is used to determine the target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and the preset winding inductance difference, the inductance determination module is used to:

[0065] Multiplying the inductance correction coefficient in the correction coefficient value by the preset winding inductance difference to obtain a first product result;

[0066] The first product result is multiplied by the dynamic switching weight coefficient in the correction coefficient value to obtain a second product result, and the second product result is determined as the target winding inductance difference of the target permanent magnet synchronous motor.

[0067] An embodiment of the present application also provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps of the permanent magnet synchronous motor torque calibration method as described above are performed.

[0068] An embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the permanent magnet synchronous motor torque calibration method as described above are executed.

[0069] The embodiments of the present application provide a permanent magnet synchronous motor torque calibration method and a calibration device, the calibration method comprising: in response to receiving a target torque value output by an expected target permanent magnet synchronous motor when working with the electric energy output by a power supply battery, obtaining the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor; based on the output voltage value set by the power supply battery, the motor speed value and the target torque value, determining the correction coefficient value corresponding to the target permanent magnet synchronous motor using a pre-calibrated correction function; determining the target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference; and based on the electromagnetic parameters, the working current vector and the target winding inductance difference, obtaining the calibration torque value actually output by the target permanent magnet synchronous motor using a preset torque model.

[0070] Compared with the method in the prior art that adopts a pre-set winding inductance difference, and the winding inductance difference remains unchanged regardless of the environment and working conditions of the permanent magnet synchronous motor, a correction coefficient value corresponding to the permanent magnet synchronous motor is determined by a pre-calibrated correction function, so as to correct the preset winding inductance difference according to the target torque value expected to be output by the permanent magnet synchronous motor when working, and use the preset torque model to obtain the calibrated torque value actually output by the permanent magnet synchronous motor, effectively quantifying the inductance change of the motor when working under various working conditions, improving the output accuracy of the torque model, and thereby improving the torque output efficiency of the permanent magnet synchronous motor drive.

[0071] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0073] Figure 1 A flow chart of a method for calibrating torque of a permanent magnet synchronous motor provided in an embodiment of the present application;

[0074] Figure 2 A schematic diagram of the structure of a permanent magnet synchronous motor torque calibration device provided in an embodiment of the present application;

[0075] Figure 3 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0076] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0077] Research has found that at present, in the method of determining the actual torque value output by the permanent magnet synchronous motor through the torque model, the winding inductance difference used is pre-set, and the winding inductance difference remains unchanged regardless of the environment and working conditions of the permanent magnet synchronous motor, which causes the actual torque value output by the torque model to deviate, reduces the output accuracy of the torque model, and thereby reduces the torque output efficiency of the permanent magnet synchronous motor drive.

[0078] Based on this, an embodiment of the present application provides a method for calibrating the torque of a permanent magnet synchronous motor, in which a correction coefficient value corresponding to the permanent magnet synchronous motor is determined by a pre-calibrated correction function, so as to correct the preset winding inductance difference according to the target torque value expected to be output by the permanent magnet synchronous motor when working, and use a preset torque model to obtain the calibrated torque value actually output by the permanent magnet synchronous motor, thereby effectively quantifying the inductance change of the motor when working under various working conditions, improving the output accuracy of the torque model, and thereby improving the torque output efficiency of the permanent magnet synchronous motor drive.

[0079] See also Figure 1 , Figure 1 This is a flow chart of a method for calibrating the torque of a permanent magnet synchronous motor provided in an embodiment of the present application. Figure 1 As shown in, the permanent magnet synchronous motor torque calibration method provided in the embodiment of the present application includes:

[0080] S101. In response to receiving a target torque value that a target permanent magnet synchronous motor is expected to output when operating using electric energy output by a power supply battery, obtaining a motor speed value, electromagnetic parameters, and an operating current vector of the target permanent magnet synchronous motor.

[0081] It should be noted that the target permanent magnet synchronous motor is usually used in vehicles. The permanent magnet synchronous motor (PMSM) is an electric motor. The rotating magnetic field generated by the stator in the permanent magnet synchronous motor and the magnetic field formed by the permanent magnets on the rotor in the permanent magnet synchronous motor rotate at the same speed, thereby realizing the synchronous operation of the rotor and the stator.

[0082] Specifically, based on Faraday's law of electromagnetic induction, when the stator winding of the permanent magnet synchronous motor is energized, a rotating magnetic field will be generated. This rotating magnetic field will interact with the permanent magnets fixed on the rotor, thereby generating torque to make the rotor rotate. Due to the presence of permanent magnets, the motor can achieve a very high power factor and maintain efficient operation over a wide speed range.

[0083] In an embodiment of the present application, when the target permanent magnet synchronous motor receives a target torque value sent by a host computer that it is expected to output when working using the electric energy output by the power supply battery, in order to make the torque value actually output by the vehicle close to the target torque value, it is necessary to improve the accuracy of the vehicle's detection of the actual torque value output by the target permanent magnet synchronous motor. The actual torque value output by the target permanent magnet synchronous motor is generally detected in the vehicle by calculating the torque model, and the result of the calculation is determined as the actual torque value output.

[0084] In one possible implementation manner of the present application, the calculation formula of the preset torque model is as follows.

[0085]

[0086] Wherein, T is the torque value calculated by the preset torque model; P p The number of pole pairs preset for the target permanent magnet synchronous motor; ψ f is the rotor flux value of the target permanent magnet synchronous motor; i d and i q are the working current vectors of the target permanent magnet synchronous motor; (L d -L q ) is the winding inductance difference.

[0087] Here, when performing vector control (Field-Oriented Control, FOC) on a permanent magnet synchronous motor, the dq0 transformation (also called Park transformation) is usually used to convert the variables in the three-phase stationary coordinate system into a two-phase rotating coordinate system including the d-axis and the q-axis, where the d-axis is consistent with the direction of the motor rotor pole, and the q-axis leads the d-axis by 90 electrical degrees.

[0088] Based on this, it should be understood that the working current vector includes corresponding working currents in the d-axis and q-axis directions; the winding inductance difference is the difference between the equivalent inductance of the motor in the d-axis direction and the equivalent inductance of the motor in the q-axis direction.

[0089] In this step, the electromagnetic parameters include a preset number of pole pairs and a rotor flux value; a sensor is used to detect the motor speed value, operating temperature value and back electromotive force of the target permanent magnet synchronous motor, and the rotor flux value and operating current vector of the target permanent magnet synchronous motor are further determined.

[0090] Among them, the preset number of pole pairs refers to half the number of poles of the magnetic field formed by the permanent magnet winding on the motor rotor. For example, if a permanent magnet synchronous motor rotor has 8 poles (i.e., 4 south poles and 4 north poles), then the number of pole pairs of the permanent magnet synchronous motor is 4.

[0091] In one embodiment of the present application, in a specific implementation, the step of obtaining the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor in step S101 may include:

[0092] S1011. Obtain a motor speed value, an operating temperature value, and a back electromotive force of the target permanent magnet synchronous motor detected by a sensor provided in the target permanent magnet synchronous motor.

[0093] In this step, the speed sensor and temperature sensor set in the target permanent magnet synchronous motor are used to detect the motor speed value and operating temperature value, and a high-speed ADC device is used to sample the terminal voltage of the motor, and the corresponding signal of the back electromotive force is separated from the terminal voltage to obtain the motor speed value, operating temperature value and back electromotive force.

[0094] The back electromotive force is a voltage generated by cutting magnetic flux lines when the target permanent magnet synchronous motor rotates, and the back electromotive force is the result of changes in the magnetic field inside the motor.

[0095] S1012. Determine a rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value, and the back electromotive force.

[0096] In this step, the rotor flux value to be corrected is calculated using the correspondence between the motor speed value, the back electromotive force and the rotor flux value, and the rotor flux value to be corrected is corrected based on the operating temperature value to obtain the rotor flux value of the target permanent magnet synchronous motor.

[0097] In one implementation of the present application, during specific implementation, step S1012 may include:

[0098] S10121. Based on the motor speed value and the back electromotive force, determine the rotor flux value to be corrected of the target permanent magnet synchronous motor using a preset flux calculation formula.

[0099] In the embodiment of the present application, the expression of the preset magnetic flux calculation formula is as follows.

[0100] E=k e ωψ f .

[0101] Where, E is the back electromotive force of the target permanent magnet synchronous motor; k e is the back electromotive force constant of the target permanent magnet synchronous motor; ω is the motor speed value of the target permanent magnet synchronous motor; ψ f is the rotor flux value to be corrected of the target permanent magnet synchronous motor.

[0102] S10122. Based on the operating temperature value, correct the rotor flux value to be corrected to determine the rotor flux value of the target permanent magnet synchronous motor.

[0103] In the embodiments of the present application, the influence of temperature on motor parameters is significant, especially in the case of long-term operation or high power output, the change of temperature will cause the change of parameters such as motor winding resistance and inductance, thereby affecting the calculation result of the rotor flux value.

[0104] In this step, the rotor flux value to be corrected is corrected based on the operating temperature value to determine the rotor flux value of the target permanent magnet synchronous motor; wherein the rotor flux value refers to the product of the magnetic flux passing through the stator winding and the number of winding turns.

[0105] S1013. Based on the pre-calibrated motor efficiency value and the target torque value of the target permanent magnet synchronous motor, determine the operating current vector of the target permanent magnet synchronous motor using a preset current distribution scheme.

[0106] In this step, in order to enable the target permanent magnet synchronous motor to output the target torque value under the pre-calibrated motor efficiency value to achieve the optimal efficiency output of the motor, it is necessary to allocate the d-axis current and q-axis current included in the working current vector of the target permanent magnet synchronous motor in combination with the target torque value under the pre-calibrated efficiency value of the target permanent magnet that exhibits maximum efficiency.

[0107] Here, the preset current distribution scheme is a scheme set in advance by conducting an optimal efficiency experiment on the target permanent magnet synchronous motor.

[0108] S102: Based on the output voltage value set by the power supply battery, the motor speed value and the target torque value, a correction coefficient value corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated correction function.

[0109] In the embodiment of the present application, since the winding inductance difference is an important parameter that affects the accuracy of the torque model when the torque model calculates the torque value, and it is difficult to quantify the value and change law of the winding inductance from a mathematical and physical perspective, the torque model accuracy can be improved by using a pre-calibrated correction function to determine the correction coefficient value to quantify the change in the winding inductance difference.

[0110] Specifically, since the operating conditions of the permanent magnet synchronous motor may change during operation, the operating current vector of the permanent magnet synchronous motor will affect the core saturation in the motor, thereby affecting the size of the winding inductance. At the same time, the operating current vector needs to be decomposed into equivalent currents on the d-axis and q-axis. Therefore, the effects of the currents on the d-axis and q-axis on the core saturation are also different.

[0111] Here, with respect to the q-axis, when the motor output torque increases, the q-axis current increases, causing the q-axis magnetic circuit to be saturated, causing the q-axis inductance to decrease accordingly; in addition, with respect to the d-axis, when the motor operates in a weak magnetic state, the d-axis current increases in the opposite direction, and the d-axis magnetic circuit is in a weak magnetic state. At this time, since the d-axis magnetic flux is weakened, the d-axis inductance increases, but since the magnetic resistance of the d-axis magnetic circuit is larger than that of the q-axis magnetic circuit, under the same current amplitude, the change in the d-axis inductance is smaller than the change in the q-axis inductance.

[0112] In one implementation of the present application, during specific implementation, step S102 may include:

[0113] S1021. Based on the motor speed value and the target torque value, determine the inductance correction coefficient corresponding to the target permanent magnet synchronous motor using a pre-calibrated first correction function to quantify the change in the winding inductance difference under steady-state conditions.

[0114] In an embodiment of the present application, considering that there is a strong correlation between the change in winding inductance and the change in current, and the current is determined by the torque, the first correction function is calibrated based on the motor speed value and the target torque value to determine the inductance correction coefficient corresponding to the target permanent magnet synchronous motor, so that the change in the winding inductance difference can be quantified under steady-state conditions.

[0115] The pre-calibrated first correction function may output an inductance correction coefficient based on the motor speed value and the target torque value.

[0116] In one embodiment of the present application, in a specific implementation, the step of pre-calibrating the first correction function in step S1021 may include:

[0117] Step 11: Use a test bench to control the target permanent magnet synchronous motor to start a first calibration test at a preset working voltage value and a preset temperature value.

[0118] In this step, when the rotor flux value and the operating current vector of the target permanent magnet synchronous motor have been determined, the test bench is set to a preset operating voltage value according to the main body design of the target permanent magnet synchronous motor, and a cooling mode that meets the target permanent magnet synchronous motor is set to control the target permanent magnet synchronous motor to start the first calibration test at the preset operating voltage value and in accordance with the cooling requirements of the target permanent magnet synchronous motor.

[0119] Step 12. In the first calibration test, based on a preset plurality of first value pairs including test speed values ​​and first test torque values ​​corresponding to each other, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the first test torque value included in each of the first value pairs to obtain a detected first measured torque value of the target permanent magnet synchronous motor.

[0120] In an embodiment of the present application, since the first correction function is an inductance correction coefficient for the winding inductance difference based on the motor speed value and the target torque value output, before performing the first calibration test, it is necessary to preset multiple first value pairs according to the actual working requirements of the motor, wherein each first value pair includes a test speed value and a first test torque value corresponding thereto.

[0121] In this step, the dynamometer is used to control the target permanent magnet synchronous motor to operate according to each first value pair including a test speed value and a first test torque value corresponding thereto, so as to obtain a first measured torque value of the target permanent magnet synchronous motor detected by a torque sensor.

[0122] Step 13: For each of the test speed values ​​and the first test torque values ​​included in the first value pair, based on preset test electromagnetic parameters, test winding inductance difference and test current vector, use the torque model to obtain multiple first model torque values ​​actually output by the target permanent magnet synchronous motor.

[0123] In this step, for each of the test speed values ​​and the first test torque values ​​included in the first numerical pair, the pre-set test electromagnetic parameters, the test winding inductance difference and the test current vector are respectively input into the torque model to obtain multiple first model torque values ​​actually output by the target permanent magnet synchronous motor.

[0124] Step 14: Based on the difference between the first measured torque value and each of the first model torque values, determine the inductance correction coefficient corresponding to each of the first value pairs by adjusting parameters, so that the first model torque value and each of the first measured torque values ​​are approximately equal.

[0125] In this step, the dynamometer is dragged to the test speed value, the upper computer gives the corresponding instruction of the first test torque value, observes the difference between the first model torque value output by the torque model and the first measured torque value detected by the torque sensor set on the dynamometer, and based on the difference, adjusts the corresponding inductance correction coefficient to make the first model torque value and each of the first measured torque values ​​as equal as possible.

[0126] Step 15: Based on the inductance correction coefficient corresponding to each of the first value pairs, obtain the first correction function through function fitting.

[0127] In this step, based on the inductance correction coefficient corresponding to each first numerical value, that is, the inductance correction coefficient corresponding to each test speed value and the corresponding first test torque value, a first correction coefficient table is obtained, and based on the first correction coefficient table, the first correction function is obtained by function fitting.

[0128] S1022. Based on the output voltage value set by the power supply battery and the motor speed value, a pre-calibrated second correction function is used to determine the dynamic switching weight coefficient corresponding to the target permanent magnet synchronous motor, so as to quantify the change in the winding inductance difference when switching the operating conditions under different output voltage values.

[0129] In an embodiment of the present application, in order to ensure that parameters such as the inductance and saturation of the target permanent magnet synchronous motor do not change suddenly when the target permanent magnet synchronous motor switches between the motoring condition and the generating condition at a low motor speed, a dynamic switching weight coefficient is introduced for the winding inductance difference.

[0130] Furthermore, considering that the motor can support output voltage values ​​under different voltage platforms, and the motor voltage and speed values ​​will also change when switching between electric operating conditions and generating operating conditions, the second correction function is calibrated based on the output voltage value and motor speed value set by the power supply battery to determine the dynamic switching weight coefficient corresponding to the target permanent magnet synchronous motor, which can quantify the change in the winding inductance difference when switching operating conditions under different output voltage values.

[0131] In one embodiment of the present application, in a specific implementation, the step of pre-calibrating the second correction function in step S1022 may include:

[0132] Step 21: Use a test bench to control the target permanent magnet synchronous motor to start a second calibration test at a second test torque value and a preset temperature value.

[0133] In this step, when the rotor flux value, working current vector and first correction function of the target permanent magnet synchronous motor have been determined, the test bench is set to a cooling mode that meets the target permanent magnet synchronous motor according to the main body design of the target permanent magnet synchronous motor, and an instruction for a second test torque value under motoring and generating conditions is issued to the motor to control the target permanent magnet synchronous motor to start a second calibration test according to the second test torque value and a preset temperature value in accordance with the cooling requirements of the target permanent magnet synchronous motor.

[0134] Wherein, the second test torque value at least includes a test torque value under an electric working condition and a test torque value under a power generating working condition.

[0135] Step 22. In the second calibration test, based on a preset plurality of second value pairs including test speed values ​​and test voltage values, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and test voltage value included in each of the second value pairs to obtain a second measured torque value of the target permanent magnet synchronous motor.

[0136] In an embodiment of the present application, since the second correction function is a dynamic switching weight coefficient for the winding inductance difference output based on the motor speed value and the test voltage value, before performing the second calibration test, it is necessary to preset multiple second value pairs according to the actual working requirements of the motor, wherein each second value pair includes a test speed value and a corresponding first test torque value.

[0137] In this step, the dynamometer is used to control the target permanent magnet synchronous motor to operate according to each first value pair including a test speed value and a test voltage value corresponding thereto, so as to obtain a second measured torque value of the target permanent magnet synchronous motor detected by a torque sensor.

[0138] Step 23, for each of the test speed values ​​and test voltage values ​​included in the second value pair, based on the inductance correction coefficient and pre-set test electromagnetic parameters, test winding inductance difference and test current vector, use the torque model to obtain multiple second model torque values ​​actually output by the target permanent magnet synchronous motor.

[0139] In this step, for each test speed value and test voltage value included in the second numerical pair, the pre-set test electromagnetic parameters, the test winding inductance difference, the test current vector and the inductance correction coefficient determined by the first correction function are respectively input into the torque model to obtain multiple second model torque values ​​actually output by the target permanent magnet synchronous motor.

[0140] Step 24: Based on the difference between the second measured torque value and each of the second model torque values, determine the dynamic switching weight coefficient corresponding to each of the second value pairs through parameter adjustment so that the second measured torque value and each of the second model torque values ​​approach equality.

[0141] In this step, the dynamometer is dragged to the test speed value, and the test bench is used to output the test voltage value for the target permanent magnet synchronous motor, and the difference between the second model torque value output by the torque model and the second measured torque value detected by the torque sensor set on the dynamometer is observed, and based on the difference, the corresponding inductance correction coefficient is adjusted to make the second model torque value and each of the second measured torque values ​​as equal as possible.

[0142] Step 25: Based on the dynamic switching weight coefficient corresponding to each of the second value pairs, obtain the second correction function through function fitting.

[0143] In this step, based on the dynamic switching weight coefficient corresponding to each second numerical value, that is, the dynamic switching weight coefficient corresponding to each test speed value and the corresponding test voltage value, a second correction coefficient table is obtained, and based on the second correction coefficient table, the second correction function is obtained by function fitting.

[0144] S1023. Determine the inductance correction coefficient and the dynamic switching weight coefficient as correction coefficient values ​​corresponding to the target permanent magnet synchronous motor.

[0145] In an embodiment of the present application, the correction coefficient value corresponding to the target permanent magnet synchronous motor includes an inductance correction coefficient and a dynamic switching weight coefficient.

[0146] S103. Determine a target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference.

[0147] In an embodiment of the present application, the preset winding inductance difference is multiplied with the inductance correction coefficient and the dynamic switching weight coefficient in the correction coefficient value respectively, and the obtained product result is determined as the target winding inductance difference of the target permanent magnet synchronous motor.

[0148] In one implementation of the present application, during specific implementation, step S103 may include:

[0149] S1031. Multiply the inductance correction coefficient in the correction coefficient value by a preset winding inductance difference to obtain a first product result.

[0150] S1032. Multiply the first product result by the dynamic switching weight coefficient in the correction coefficient value to obtain a second product result, and determine the second product result as the target winding inductance difference of the target permanent magnet synchronous motor.

[0151] In one possible implementation manner of the present application, the preset winding inductance difference is an inherent parameter in the standard permanent magnet synchronous motor. For example, the preset winding inductance difference can be set to 0.0002.

[0152] S104. Based on the electromagnetic parameters, the working current vector and the target winding inductance difference, a preset torque model is used to obtain a calibrated torque value actually output by the target permanent magnet synchronous motor.

[0153] In this step, the preset pole pair number and rotor flux value, working current vector and target winding inductance difference included in the electromagnetic parameters are input into the preset torque model, and the calibrated torque value actually output by the target permanent magnet synchronous motor is obtained through model calculation.

[0154] In the embodiment of the present application, the calculation formula of the preset torque model is as follows.

[0155]

[0156] Wherein, T is the calibrated torque value actually output by the target permanent magnet synchronous motor; P p The number of pole pairs preset for the target permanent magnet synchronous motor; ψ f is the rotor flux value of the target permanent magnet synchronous motor; i d and i q are the working current vectors of the target permanent magnet synchronous motor; (L d -L q ) is the target winding inductance difference.

[0157] The permanent magnet synchronous motor torque calibration method provided in the embodiment of the present application determines the correction coefficient value corresponding to the permanent magnet synchronous motor through a pre-calibrated correction function, so as to correct the preset winding inductance difference according to the target torque value expected to be output by the permanent magnet synchronous motor when working, and uses the preset torque model to obtain the calibrated torque value actually output by the permanent magnet synchronous motor, effectively quantifying the inductance change of the motor when working under various working conditions, improving the output accuracy of the torque model, and thereby improving the torque output efficiency of the permanent magnet synchronous motor drive.

[0158] See also Figure 2 , Figure 2 This is a schematic diagram of the structure of a permanent magnet synchronous motor torque calibration device provided in an embodiment of the present application. Figure 2 As shown in , the calibration device 200 includes:

[0159] The data acquisition module 210 is used to obtain the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor in response to receiving the target torque value output by the target permanent magnet synchronous motor when the target permanent magnet synchronous motor is working with the electric energy output by the power supply battery from the host computer;

[0160] A coefficient determination module 220, configured to determine a correction coefficient value corresponding to the target permanent magnet synchronous motor using a pre-calibrated correction function based on the output voltage value set by the power supply battery, the motor speed value and the target torque value;

[0161] an inductance determination module 230, configured to determine a target winding inductance difference value of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference value;

[0162] The torque determination module 240 is used to obtain a calibrated torque value actually output by the target permanent magnet synchronous motor based on the electromagnetic parameters, the working current vector and the target winding inductance difference using a preset torque model.

[0163] Further, the electromagnetic parameters include a preset number of pole pairs and a rotor flux value; when the data acquisition module 210 is used to acquire the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor, the data acquisition module 210 is used to:

[0164] Acquire a motor speed value, an operating temperature value, and a back electromotive force of the target permanent magnet synchronous motor detected by a sensor provided in the target permanent magnet synchronous motor;

[0165] Determining a rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force;

[0166] Based on the pre-calibrated motor efficiency value of the target permanent magnet synchronous motor and the target torque value, a working current vector of the target permanent magnet synchronous motor is determined using a preset current distribution scheme.

[0167] Further, when the data acquisition module 210 is used to determine the rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force, the data acquisition module 210 is used to:

[0168] Based on the motor speed value and the back electromotive force, a preset flux calculation formula is used to determine the rotor flux value to be corrected of the target permanent magnet synchronous motor;

[0169] Based on the operating temperature value, the rotor flux value to be corrected is corrected to determine the rotor flux value of the target permanent magnet synchronous motor.

[0170] Further, when the coefficient determination module 220 is used to determine the correction coefficient value corresponding to the target permanent magnet synchronous motor based on the output voltage value set by the power supply battery, the motor speed value and the target torque value using a pre-calibrated correction function, the coefficient determination module 220 is used to:

[0171] Based on the motor speed value and the target torque value, an inductance correction coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated first correction function to quantify a change in winding inductance difference under steady-state conditions;

[0172] Based on the output voltage value set by the power supply battery and the motor speed value, a dynamic switching weight coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated second correction function to quantify the change in the winding inductance difference when the operating mode is switched under different output voltage values;

[0173] The inductance correction coefficient and the dynamic switching weight coefficient are determined as correction coefficient values ​​corresponding to the target permanent magnet synchronous motor.

[0174] Further, when the coefficient determination module 220 is used to pre-calibrate the first correction function, the coefficient determination module 220 is used to:

[0175] Using a test bench to control the target permanent magnet synchronous motor to start a first calibration test at a preset working voltage value and a preset temperature value;

[0176] In the first calibration test, based on a plurality of preset first value pairs including a test speed value and a first test torque value, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the first test torque value included in each of the first value pairs, so as to obtain a first measured torque value of the target permanent magnet synchronous motor;

[0177] For each of the test speed value and the first test torque value included in the first value pair, based on the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of first model torque values ​​actually output by the target permanent magnet synchronous motor;

[0178] Based on the difference between the first measured torque value and each of the first model torque values, determining the inductance correction coefficient corresponding to each of the first value pairs by adjusting parameters, so that the first model torque value and each of the first measured torque values ​​are close to being equal;

[0179] The first correction function is obtained by function fitting based on the inductance correction coefficient corresponding to each of the first value pairs.

[0180] Further, when the coefficient determination module 220 is used to pre-calibrate the second correction function, the coefficient determination module 220 is used to:

[0181] Using the test bench to control the target permanent magnet synchronous motor to start a second calibration test at a second test torque value and a preset temperature value;

[0182] In the second calibration test, based on a plurality of preset second value pairs including test speed values ​​and test voltage values, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the test voltage value included in each of the second value pairs, so as to obtain a second measured torque value of the target permanent magnet synchronous motor;

[0183] For each test speed value and test voltage value included in the second value pair, based on the inductance correction coefficient and the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of second model torque values ​​actually output by the target permanent magnet synchronous motor;

[0184] Based on the difference between the second measured torque value and each of the second model torque values, determining the dynamic switching weight coefficient corresponding to each of the second value pairs by adjusting parameters, so that the second measured torque value and each of the second model torque values ​​approach equality;

[0185] Based on the dynamic switching weight coefficient corresponding to each of the second value pairs, the second correction function is obtained by function fitting.

[0186] Further, when the inductance determination module 230 is used to determine the target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and the preset winding inductance difference, the inductance determination module 230 is used to:

[0187] Multiplying the inductance correction coefficient in the correction coefficient value by the preset winding inductance difference to obtain a first product result;

[0188] The first product result is multiplied by the dynamic switching weight coefficient in the correction coefficient value to obtain a second product result, and the second product result is determined as the target winding inductance difference of the target permanent magnet synchronous motor.

[0189] The permanent magnet synchronous motor torque calibration device provided in the embodiment of the present application determines the correction coefficient value corresponding to the permanent magnet synchronous motor through a pre-calibrated correction function, so as to correct the preset winding inductance difference according to the target torque value expected to be output by the permanent magnet synchronous motor when working, and uses the preset torque model to obtain the calibrated torque value actually output by the permanent magnet synchronous motor, effectively quantifying the inductance change of the motor when working under various working conditions, improving the output accuracy of the torque model, and thereby improving the torque output efficiency of the permanent magnet synchronous motor drive.

[0190] See also Figure 3 , Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 3 As shown in , the electronic device 300 includes a processor 310 , a memory 320 and a bus 330 .

[0191] The memory 320 stores machine-readable instructions executable by the processor 310. When the electronic device 300 is running, the processor 310 communicates with the memory 320 via the bus 330. When the machine-readable instructions are executed by the processor 310, the above-mentioned Figure 1 The steps of the permanent magnet synchronous motor torque calibration method in the method embodiment shown, the specific implementation method can be referred to the method embodiment, and will not be repeated here.

[0192] The present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the computer program can execute the above-mentioned Figure 1 The steps of the permanent magnet synchronous motor torque calibration method in the method embodiment shown, the specific implementation method can be referred to the method embodiment, and will not be repeated here.

[0193] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0194] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0195] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0196] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0197] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application can essentially be embodied in the form of a software product, or in other words, the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0198] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application is described in detail with reference to the above-mentioned embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-mentioned embodiments within the technical scope disclosed in the present application, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for calibrating the torque of a permanent magnet synchronous motor, characterized in that: The calibration method comprises: In response to receiving a target torque value that the target permanent magnet synchronous motor is expected to output when working with the electric energy output by the power supply battery, obtaining a motor speed value, electromagnetic parameters and a working current vector of the target permanent magnet synchronous motor; Based on the output voltage value set by the power supply battery, the motor speed value and the target torque value, a correction coefficient value corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated correction function; Determining a target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference; Based on the electromagnetic parameters, the working current vector and the target winding inductance difference, a calibrated torque value actually output by the target permanent magnet synchronous motor is obtained using a preset torque model.

2. The method according to claim 1, characterized in that The electromagnetic parameters include a preset number of pole pairs and a rotor flux value; the step of obtaining the motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor includes: Acquire a motor speed value, an operating temperature value, and a back electromotive force of the target permanent magnet synchronous motor detected by a sensor provided in the target permanent magnet synchronous motor; Determining a rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force; Based on the pre-calibrated motor efficiency value of the target permanent magnet synchronous motor and the target torque value, a working current vector of the target permanent magnet synchronous motor is determined using a preset current distribution scheme.

3. The method according to claim 2, characterized in that The step of determining the rotor flux value of the target permanent magnet synchronous motor based on the motor speed value, the operating temperature value and the back electromotive force comprises: Based on the motor speed value and the back electromotive force, a preset flux calculation formula is used to determine the rotor flux value to be corrected of the target permanent magnet synchronous motor; Based on the operating temperature value, the rotor flux value to be corrected is corrected to determine the rotor flux value of the target permanent magnet synchronous motor.

4. The method according to claim 1, characterized in that: The method of determining a correction coefficient value corresponding to the target permanent magnet synchronous motor by using a pre-calibrated correction function based on the output voltage value set by the power supply battery, the motor speed value and the target torque value includes: Based on the motor speed value and the target torque value, an inductance correction coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated first correction function to quantify a change in winding inductance difference under steady-state conditions; Based on the output voltage value set by the power supply battery and the motor speed value, a dynamic switching weight coefficient corresponding to the target permanent magnet synchronous motor is determined using a pre-calibrated second correction function to quantify the change in the winding inductance difference when the operating mode is switched under different output voltage values; The inductance correction coefficient and the dynamic switching weight coefficient are determined as correction coefficient values ​​corresponding to the target permanent magnet synchronous motor.

5. The method according to claim 4, characterized in that The first correction function is pre-calibrated by the following steps: Using a test bench to control the target permanent magnet synchronous motor to start a first calibration test at a preset working voltage value and a preset temperature value; In the first calibration test, based on a plurality of preset first value pairs including a test speed value and a first test torque value, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the first test torque value included in each of the first value pairs, so as to obtain a first measured torque value of the target permanent magnet synchronous motor; For each of the test speed value and the first test torque value included in the first value pair, based on the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of first model torque values ​​actually output by the target permanent magnet synchronous motor; Based on the difference between the first measured torque value and each of the first model torque values, determining the inductance correction coefficient corresponding to each of the first value pairs by adjusting parameters, so that the first model torque value and each of the first measured torque values ​​are close to being equal; The first correction function is obtained by function fitting based on the inductance correction coefficient corresponding to each of the first value pairs.

6. The method according to claim 5, characterized in that The second correction function is pre-calibrated by the following steps: Using the test bench to control the target permanent magnet synchronous motor to start a second calibration test at a second test torque value and a preset temperature value; In the second calibration test, based on a plurality of preset second value pairs including test speed values ​​and test voltage values, a dynamometer is used to control the target permanent magnet synchronous motor to operate according to the test speed value and the test voltage value included in each of the second value pairs, so as to obtain a second measured torque value of the target permanent magnet synchronous motor; For each test speed value and test voltage value included in the second value pair, based on the inductance correction coefficient and the preset test electromagnetic parameters, the test winding inductance difference and the test current vector, the torque model is used to obtain a plurality of second model torque values ​​actually output by the target permanent magnet synchronous motor; Based on the difference between the second measured torque value and each of the second model torque values, determining the dynamic switching weight coefficient corresponding to each of the second value pairs by adjusting parameters, so that the second measured torque value and each of the second model torque values ​​approach equality; Based on the dynamic switching weight coefficient corresponding to each of the second value pairs, the second correction function is obtained by function fitting.

7. The method according to claim 4, characterized in that The step of determining a target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference includes: Multiplying the inductance correction coefficient in the correction coefficient value by the preset winding inductance difference to obtain a first product result; The first product result is multiplied by the dynamic switching weight coefficient in the correction coefficient value to obtain a second product result, and the second product result is determined as the target winding inductance difference of the target permanent magnet synchronous motor.

8. A permanent magnet synchronous motor torque calibration device, characterized in that: The calibration device comprises: A data acquisition module, configured to obtain a motor speed value, electromagnetic parameters and working current vector of the target permanent magnet synchronous motor in response to receiving a target torque value output by the desired target permanent magnet synchronous motor when the motor is operated by using the electric energy output by the power supply battery from the host computer; A coefficient determination module, used to determine the correction coefficient value corresponding to the target permanent magnet synchronous motor using a pre-calibrated correction function based on the output voltage value set by the power supply battery, the motor speed value and the target torque value; an inductance determination module, configured to determine a target winding inductance difference of the target permanent magnet synchronous motor based on the correction coefficient value and a preset winding inductance difference; The torque determination module is used to obtain a calibrated torque value actually output by the target permanent magnet synchronous motor using a preset torque model based on the electromagnetic parameters, the working current vector and the target winding inductance difference.

9. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor and the memory communicate through the bus, and the machine-readable instructions are executed by the processor to execute the steps of the permanent magnet synchronous motor torque calibration method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the permanent magnet synchronous motor torque calibration method according to any one of claims 1 to 7 are executed.

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