Parameter calibration method, device and equipment of asynchronous motor and storage medium

Abstract

The invention discloses a parameter calibration method, device and equipment for an asynchronous motor and a storage medium, and the method comprises the steps: obtaining a plurality of test currents, and carrying out the multiple parameter calibration operation of the asynchronous motor based on the plurality of test currents, calibrating stator leakage inductance and rotor leakage inductance corresponding to the test current; on the basis of the calibrated no-load test parameters and stator and rotor leakage inductance, calibrating excitation inductance and stator and rotor inductance corresponding to the test current; calibrating the stator resistance corresponding to the test current based on the calibrated stator temperature; calibrating steady-state rotor resistance corresponding to the test current based on the calibrated stator resistance, stator and rotor leakage inductance and locked-rotor test parameters; and based on the calibrated steady-state rotor resistance, the stator temperature, the stator and rotor leakage inductance, the stator and rotor inductance and the excitation inductance, calibrating the dynamic rotor resistance corresponding to the test current. The calibration method can ensure the parameter accuracy of the asynchronous motor and improve the control precision and stability of the asynchronous motor.

Description

Technical Field

[0001] The present invention relates to the field of motor technology, and in particular to a parameter calibration method, device, equipment and storage medium for an asynchronous motor. Background Art

[0002] With the continuous progress of AC speed regulation theory and power electronics technology, asynchronous motor speed regulation systems based on field-oriented vector control technology are increasingly gaining widespread attention and application. This speed regulation system can achieve precise speed or torque control of asynchronous motors, and its performance depends largely on the accurate calculation of the motor model. However, the accuracy of the motor model directly depends on the accuracy of the motor parameters. Therefore, the accuracy of the asynchronous motor parameters has a crucial impact on the overall control effect of the system.

[0003] In the control of asynchronous motors, motor parameters such as stator and rotor inductance, resistance and leakage inductance have a great influence on the final orientation angle. If the estimated orientation angle is mismatched or differs greatly from the actual value, the asynchronous motor cannot generate the desired torque in the torque control mode, and the asynchronous motor is in an over-excitation or under-excitation state, resulting in problems such as motor overheating or control divergence.

[0004] Therefore, how to ensure the accuracy of asynchronous motor parameters and improve the accuracy and stability of asynchronous motor control is a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of the above problems, the present invention is proposed to provide a method, device, equipment and storage medium for calibrating parameters of an asynchronous motor that overcomes the above problems or at least partially solves the above problems. The method takes into account the dynamic changes of various motor parameters of the asynchronous motor under different temperatures and currents, and can improve the accuracy of the calibrated motor parameters, thereby facilitating improving the accuracy and stability of asynchronous motor control.

[0006] In a first aspect, a parameter calibration method for an asynchronous motor is provided, the parameter calibration method comprising:

[0007] A plurality of test currents are obtained, and for each test current, a parameter calibration operation is performed on the asynchronous motor based on the test current, wherein the parameter calibration operation includes:

[0008] Performing a stall test on the asynchronous motor, and calibrating a first motor parameter corresponding to the test current based on a stall test parameter corresponding to the test current, wherein the first motor parameter includes at least a stator leakage inductance and a rotor leakage inductance;

[0009] Performing a no-load test on the asynchronous motor, and calibrating a second motor parameter corresponding to the test current based on a no-load test parameter corresponding to the test current and the first motor parameter, wherein the second motor parameter includes at least a magnetizing inductance, a stator inductance, and a rotor inductance;

[0010] Acquire the stator temperature corresponding to the test current, and calibrate the stator resistance corresponding to the test current based on the stator temperature corresponding to the test current;

[0011] Calibrate the steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter and the locked-rotor test parameter;

[0012] The dynamic rotor resistance corresponding to the test current is calibrated based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter, and the second motor parameter.

[0013] Optionally, calibrating the stator resistance corresponding to the test current based on the stator temperature corresponding to the test current includes:

[0014] According to the following relationship between stator temperature and stator resistance, calibrate the stator resistance corresponding to the test current:

[0015] Rs=Rs0*(1+Ks0*(Ts1-T0));

[0016] Wherein, Rs is the stator resistance, Rs0 is the pre-measured reference stator resistance of the asynchronous motor at the test temperature T0, Ks0 is the stator material temperature coefficient, and Ts1 is the stator temperature.

[0017] Optionally, the locked-rotor test parameters include at least a locked-rotor current, a locked-rotor voltage and a first power factor corresponding to the test current;

[0018] The step of calibrating the first motor parameter corresponding to the test current based on the locked-rotor test parameter corresponding to the test current includes:

[0019] The first motor parameter corresponding to the test current is calibrated based on the following formula:

[0020]

[0021] Among them, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, φ1 is the first power factor, f el For a given frequency.

[0022] Optionally, the no-load test parameters include at least a no-load current, a no-load voltage and a second power factor corresponding to the test current;

[0023] The step of calibrating the second motor parameter corresponding to the test current based on the no-load test parameter corresponding to the test current and the first motor parameter includes:

[0024] The second motor parameter corresponding to the test current is calibrated based on the following formula:

[0025]

[0026] L s =L m +L ls ;

[0027] L r =L m +L lr ;

[0028] Among them, L m is the excitation inductance, I2 is the no-load current, U2 is the no-load voltage, φ2 is the second power factor, f el For the given frequency, L Is is the stator leakage inductance, L s is the stator inductance, L r is the rotor inductance, L Ir is the rotor leakage inductance.

[0029] Optionally, calibrating the steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter, and the locked-rotor test parameter includes:

[0030] The steady-state rotor resistance corresponding to the test current is calibrated based on the following formula:

[0031]

[0032] Wherein, Rr is the steady-state rotor resistance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, and f el For a given frequency, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance and Rs is the stator resistance.

[0033] Optionally, calibrating the dynamic rotor resistance corresponding to the test current based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter, and the second motor parameter includes:

[0034] Determining a rotor temperature corresponding to the test current based on the steady-state rotor resistance corresponding to the test current;

[0035] Based on the rotor temperature and the stator temperature corresponding to the test current, determining a temperature mapping relationship between the rotor temperature and the stator temperature corresponding to the test current;

[0036] Based on the second motor parameter corresponding to the test current, determine the target rotor resistance and target slip corresponding to the test current when the output torque of the asynchronous motor is the maximum torque and the electrical angular velocity and electrical angle output by the magnetic flux current model and the dq-axis current model of the asynchronous motor are the same;

[0037] Based on the target rotor resistance and target slip corresponding to the test current, determining the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current;

[0038] Determine the temperature rise rate ratio of the stator and rotor corresponding to the test current based on the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current;

[0039] Based on the stator temperature corresponding to the test current, the temperature mapping relationship and the temperature rise rate ratio, the dynamic rotor resistance corresponding to the test current in each control cycle of the asynchronous motor is calibrated.

[0040] Optionally, the dynamic rotor resistance corresponding to the test current is calibrated in each control cycle of the asynchronous motor based on the stator temperature corresponding to the test current, the temperature mapping relationship and the temperature rise rate ratio, including:

[0041] The dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor is calibrated based on the following formula:

[0042] Rrb=[Kr0*ζx*(ηx*Tsx-η1*Ts1)+1]*Rra;

[0043] Among them, η1, Ts1 and Rra are respectively the temperature mapping relationship, the stator temperature and the dynamic rotor resistance corresponding to the test current in the previous control cycle of the asynchronous motor; ηx, Tsx, ζx and Rrb are respectively the temperature mapping relationship, the stator temperature, the temperature rise rate ratio and the dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor; Kr0 is the temperature coefficient of the rotor material.

[0044] In a second aspect, a parameter calibration device for an asynchronous motor is provided, the parameter calibration device is used to obtain a plurality of test currents, and for each test current, a parameter calibration operation is performed on the asynchronous motor based on the test current, the parameter calibration device comprising:

[0045] A first calibration module, used for performing a stall test on the asynchronous motor, and calibrating a first motor parameter corresponding to the test current based on a stall test parameter corresponding to the test current, wherein the first motor parameter includes at least a stator leakage inductance and a rotor leakage inductance;

[0046] A second calibration module, used for performing a no-load test on the asynchronous motor, and calibrating a second motor parameter corresponding to the test current based on the no-load test parameter corresponding to the test current and the first motor parameter, wherein the second motor parameter includes at least an excitation inductance, a stator inductance, and a rotor inductance;

[0047] A third calibration module, used for obtaining a stator temperature corresponding to the test current, and calibrating a stator resistance corresponding to the test current based on the stator temperature corresponding to the test current;

[0048] a fourth calibration module, configured to calibrate a steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter, and the locked-rotor test parameter;

[0049] A fifth calibration module is used to calibrate the dynamic rotor resistance corresponding to the test current based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter and the second motor parameter.

[0050] In a third aspect, an electronic device is provided, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the parameter calibration method as described in the first aspect by executing the computer instructions.

[0051] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the parameter calibration method as described in the first aspect.

[0052] The technical solution provided in the embodiments of the present invention has at least the following technical effects or advantages:

[0053] The present invention provides a method, device, equipment and storage medium for calibrating parameters of an asynchronous motor. The asynchronous motor is subjected to a stall test and a no-load test to obtain relevant test parameters of the asynchronous motor under a plurality of test currents when the rotor is stalled or the motor is no-loaded. On the one hand, since the current of the motor is very large under the stall condition, the influence of the leakage inductance becomes significant. Therefore, the stator and rotor leakage inductance can be more accurately calibrated through the stall test parameters. On the other hand, since the rotor current is very small under the no-load condition, the influence of the rotor resistance and leakage inductance can be ignored. Therefore, the excitation inductance and the stator and rotor inductance can be more accurately calibrated through the no-load test parameters. The parameter calibration method of the present application not only takes into account the influence of the current on each motor parameter, but also takes into account the influence of the motor temperature change on each motor parameter, associates the stator resistance with the stator temperature, and according to the relationship between the motor parameters, respectively calibrates the stator and rotor leakage inductance, inductance, resistance and excitation inductance when the motor produces temperature changes under different test currents, thereby meeting the precise calibration requirements of the motor parameters under different currents and temperatures. At the same time, when calibrating the motor rotor resistance, not only the steady-state rotor resistance of the motor in steady-state conditions is calibrated, but also the influence of the stator temperature change on the rotor resistance under dynamic conditions is considered, and the rotor resistance is associated with the stator temperature to further calibrate the dynamic rotor resistance of the motor in dynamic conditions. The efficient and reliable calibration method formed by this scheme can not only ensure the accuracy of the parameters of the asynchronous motor, improve the accuracy and stability of the asynchronous motor control, but also improve the accuracy and precision of the control angle and output torque of the asynchronous motor in the subsequent operation process, improve the dynamic responsiveness of the asynchronous motor, reduce the risk of control divergence, and prevent the motor from running in under-excitation and over-excitation states, reducing the risk of overheating of the motor.

[0054] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0056] Figure 1 It is a flow chart of a parameter calibration method of an asynchronous motor provided by an embodiment of the present invention;

[0057] Figure 2is a schematic diagram of a locked-rotor equivalent circuit provided by an embodiment of the present invention;

[0058] Figure 3 is a schematic diagram of a no-load equivalent circuit provided by an embodiment of the present invention;

[0059] Figure 4 is a stator resistance measurement equivalent principle diagram provided by an embodiment of the present invention;

[0060] Figure 5 is a flowchart of step S150 provided in an embodiment of the present invention;

[0061] Figure 6 It is a schematic diagram of verifying a dq axis current model and a magnetic flux current model provided by an embodiment of the present invention;

[0062] Figure 7 is a schematic diagram of the rotor temperature change and the stator temperature change under different test currents provided by an embodiment of the present invention;

[0063] Figure 8 It is a structural block diagram of a parameter calibration device for an asynchronous motor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0064] In order to better understand the above-mentioned technical scheme, the above-mentioned technical scheme will be described in detail below in combination with the accompanying drawings and specific implementation methods of the specification. It should be understood that the embodiments of the present disclosure and the specific features in the embodiments are detailed descriptions of the technical scheme of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0065] An embodiment of the present invention provides a method for calibrating parameters of a motor, the method comprising:

[0066] A plurality of test currents are obtained, and for each test current, a parameter calibration operation is performed on the asynchronous motor based on the test current.

[0067] In some implementations, the multiple test currents can be any current less than the maximum current of the motor. The test current can start from 0 and increase to the maximum current of the motor according to the set step size. After each change of the test current, the asynchronous motor is calibrated based on the changed test current. Since the motor temperature will be different under different test currents, the motor parameters corresponding to the multiple test currents can be calibrated by this method (including stator leakage inductance, rotor leakage inductance, excitation inductance, stator inductance, rotor inductance, stator resistance and rotor resistance, etc.), which meets the requirements for accurate calibration of motor parameters under different currents and temperatures.

[0068] Figure 1is a flow chart of a parameter calibration method for an asynchronous motor provided by an embodiment of the present invention, such as Figure 1 As shown, for each test current, the asynchronous motor is calibrated based on the test current, including:

[0069] Step S110, performing a stall test on the asynchronous motor, and calibrating first motor parameters corresponding to the test current based on the stall test parameters corresponding to the test current, the first motor parameters at least including stator leakage inductance and rotor leakage inductance.

[0070] In some embodiments, performing a stall test on an asynchronous motor may include: placing the asynchronous motor on a towing test bench, blocking the rotor of the asynchronous motor to form a stall equivalent circuit; then, through IF control, a test current I0 is given according to a set step size (for example, 30A), and the test current I0 increases from 0 to the maximum current of the motor (for example, 480A), and a fixed frequency (for example, f0=50Hz) is given. After the test bench torque and the motor temperature are stable, the corresponding stall parameters such as voltage, current and power factor are obtained through a power analyzer, and the corresponding stator temperature is recorded at the same time, as shown in Table 1 below.

[0071] Among them, the basic principle of IF control is based on the circuit model of the motor, which is equivalent to an RL circuit with an inductor and a resistor in series. In this model, there is a certain relationship between the back EMF of the motor and the change of the current. The back EMF can usually be calculated by measuring the parameters such as the voltage, current and speed of the motor. Then, according to the size and direction of the back EMF, the torque and speed of the motor are controlled by adjusting the current output by the current controller.

[0072] Table 1

[0073] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Current setting / A 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 Frequency / Hz 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 Line voltage / Vrms Line current / Arms Power Factor Phase voltage / Vrms Phase current / Arms Power factor angle / ° Cosine function Stator temperature / ℃

[0074] Figure 2 is a schematic diagram of a locked-rotor equivalent circuit provided by an embodiment of the present invention, such as Figure 2 As shown in the figure, Vph is the effective value of the phase voltage, Rs is the stator resistance, L ls is the stator leakage inductance, L lr is the rotor leakage inductance, Rr is the rotor resistance, based on the above stall equivalent circuit, the following formula can be obtained:

[0075]

[0076] Among them, U is the effective value of voltage displayed by the power analyzer, I is the effective value of current displayed by the power analyzer, fel is the stator frequency, and φ is the power factor angle.

[0077] The stator leakage inductance and the rotor leakage inductance are close in size and are very small compared to the excitation inductance. In this solution, the stator leakage inductance is made equal to the rotor leakage inductance:

[0078] L ls = L lr (2)

[0079] By transforming the above formulas (1) and (2), the calculation formula (3) for the stator leakage inductance and rotor leakage inductance corresponding to the test current can be obtained.

[0080] In some embodiments, the locked-rotor test parameters include at least a locked-rotor current (i.e., the line current in Table 1), a locked-rotor voltage (i.e., the line voltage in Table 1), and a first power factor (i.e., the power factor in Table 1) corresponding to the test current. Then, in step S110, based on the locked-rotor test parameters corresponding to the test current, calibrating the first motor parameter corresponding to the test current includes:

[0081] The first motor parameter corresponding to the test current is calibrated based on the following formula (3):

[0082]

[0083] Among them, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, φ1 is the first power factor, f el is a given frequency. I1, U1, and φ1 are detected by the power analyzer. Substituting I1, U1, and φ1 corresponding to the test current into the above formula (3) can calculate the stator leakage inductance L corresponding to the test current. Is and rotor leakage inductance L Ir .

[0084] Step S120, perform a no-load test on the asynchronous motor, and calibrate the second motor parameters corresponding to the test current based on the no-load test parameters corresponding to the test current and the first motor parameters, the second motor parameters at least including the excitation inductance, the stator inductance and the rotor inductance.

[0085] In some embodiments, performing a no-load test on an asynchronous motor may include: placing the asynchronous motor on a dragging test stand, dragging its speed to a set value, such as 1000 rpm (3 pairs of poles); then, through IF control, a test current I0 is given according to a set step size (such as 30A), the test current I0 increases from 0 to the maximum current of the motor (such as 480A), a fixed frequency (such as f0=50Hz) is given, a no-load equivalent circuit is formed, and corresponding no-load parameters such as voltage, current and power factor are obtained through a power analyzer, as shown in Table 2 below:

[0086] Table 2

[0087] Serial number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Current setting / A 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 Frequency / Hz 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 50 Line voltage / Vrms Line current / Arms Power Factor Phase voltage / Vrms Phase current / Arms Power factor angle / ° Cosine function

[0088] Figure 3is a schematic diagram of an no-load equivalent circuit provided by an embodiment of the present invention, such as Figure 3 As shown in the figure, Vph is the effective value of the phase voltage, Rs is the stator resistance, L ls is the stator leakage inductance, L Ir is the rotor leakage inductance, L m is the excitation inductance. Based on the above no-load equivalent circuit, the following formula can be obtained:

[0089]

[0090] Among them, U is the effective value of voltage displayed by the power analyzer, I is the effective value of current displayed by the power analyzer, fel is the stator frequency, and φ is the power factor angle.

[0091] In engineering practice, the stator self-inductance and rotor self-inductance are ignored, and we have:

[0092] L s = L m + L ls ; (5)

[0093] L r = L m + L lr ; (6)

[0094] By transforming the above formula (4), the calculation formula (7) of the excitation inductance corresponding to the test current can be obtained.

[0095] In some embodiments, the no-load test parameters include at least the no-load current, no-load voltage and second power factor corresponding to the test current. Then in step S120, based on the no-load test parameters corresponding to the test current and the first motor parameters, the second motor parameters corresponding to the test current are calibrated, including:

[0096] The second motor parameters corresponding to the test current are calibrated based on the following formulas (5), (6), and (7):

[0097]

[0098] L s = L m + L ls ; (5)

[0099] L r = L m + L lr ; (6)

[0100] Among them, L m is the excitation inductance, I2 is the no-load current, U2 is the no-load voltage, φ2 is the second power factor, f el For a given frequency, L Isis the stator leakage inductance, L s is the stator inductance, L r is the rotor inductance, L Ir is the rotor leakage inductance. I2, U2, and φ2 are detected by the power analyzer. Substituting I2, U2, and φ2 corresponding to the test current into the above formula (7) can calculate the excitation inductance L corresponding to the test current. m The excitation inductance L corresponding to the test current calculated according to the above formula (7) m , and the stator leakage inductance L corresponding to the test current calculated according to the above formula (3) Is and rotor leakage inductance L Ir Substituting the above formulas (5) and (6), the stator inductance L corresponding to the test current can be calculated. s and rotor inductance L r .

[0101] Step S130, obtaining the stator temperature corresponding to the test current, and calibrating the stator resistance corresponding to the test current based on the stator temperature corresponding to the test current.

[0102] In some embodiments, the asynchronous motor can be placed on a laboratory bench, and the resistance of the three-phase wiring harness connectors (UV, UW, VW wiring harness connectors) of the asynchronous motor can be measured at a set temperature T0 (for example, room temperature 25°C) using a resistance measuring instrument (for example, a milliohm meter) to obtain three resistance values ​​R1, R2, and R3, and then the average of the three measured resistance values ​​R1, R2, and R3 is taken. Figure 4 is a stator resistance measurement equivalent schematic diagram provided by an embodiment of the present invention, such as Figure 4 As shown, the resistance measuring instrument measures the sum of the two-phase stator resistance. Therefore, after taking the average value of the three resistance values, it is necessary to take half of the average value. Then, the reference stator resistance at the set temperature T0 can be determined according to the following formula (8):

[0103] Rs0=((R1+R2+R3) / 3) / 2=(R1+R2+R3) / 6; (8)

[0104] In some embodiments, in step S130, based on the stator temperature corresponding to the test current, calibrating the stator resistance corresponding to the test current includes:

[0105] According to the following relationship between stator temperature and stator resistance (9), the stator resistance corresponding to the test current is calibrated:

[0106] Rs=Rs0*(1+Ks0*(Ts1-T0)); (9)

[0107] Among them, Rs is the stator resistance, Rs0 is the pre-measured reference stator resistance of the asynchronous motor at the test temperature T0, Ks0 is the stator material temperature coefficient, and Ts1 is the stator temperature. Rs0 and T0 can be obtained by formula (8). By looking up the stator temperature corresponding to the test current in Table 1 and substituting it into the above formula (9), the stator resistance corresponding to the test current can be calculated.

[0108] Step S140, calibrating the steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter and the locked-rotor test parameter.

[0109] Exemplarily, the following formula can also be obtained based on the stalled rotor equivalent circuit in step S120:

[0110]

[0111] By transforming the above formulas (10) and (1), we can get the calculation formula (11) for the steady-state rotor resistance.

[0112] In some embodiments, step S140 may include:

[0113] The steady-state rotor resistance corresponding to the test current is calibrated based on the following formula (11):

[0114]

[0115] Among them, Rr is the steady-state rotor resistance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, and f el For a given frequency, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance and Rs is the stator resistance.

[0116] Step S150, calibrating the dynamic rotor resistance corresponding to the test current based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter, and the second motor parameter.

[0117] Figure 5 is a flow chart of step S150 provided in an embodiment of the present invention, such as Figure 5 As shown, in this embodiment, step S150 may include:

[0118] Step S151, determining the rotor temperature corresponding to the test current based on the steady-state rotor resistance corresponding to the test current.

[0119] In some embodiments, the rotor temperature Tr1 corresponding to the test current can be determined according to the following formula (12):

[0120] Tr1=(Rr / Rr0-1) / Kr0+T0; (12)

[0121] Wherein, Rr is the steady-state rotor resistance, Rr0 is the pre-measured reference rotor resistance of the asynchronous motor at the test temperature T0, and Kr0 is the rotor material temperature coefficient.

[0122] Step S152: Based on the rotor temperature and the stator temperature corresponding to the test current, determine the temperature mapping relationship between the rotor temperature and the stator temperature corresponding to the test current.

[0123] In some embodiments, the temperature mapping relationship η between the rotor temperature and the stator temperature corresponding to the test current can be determined according to the following formula (13):

[0124] η=Tr1 / Ts1; (13)

[0125] Among them, Tr1 is the rotor temperature corresponding to the test current, and Ts1 is the stator temperature corresponding to the test current. According to the above formula (13), the stator-rotor steady-state temperature ratio table ηx corresponding to the test current can be obtained.

[0126] Since the rotor resistance temperature changes dynamically in real time during the operation of the actual asynchronous motor, and the speed of change is affected by the motor operating conditions, it is not reasonable to simply obtain the relationship between the rotor temperature and the stator temperature of the asynchronous motor in a steady state. Therefore, this embodiment also considers the reasonable correspondence between the rotor temperature and the stator temperature of the asynchronous motor under dynamic multi-operating conditions to determine the temperature rise slope of the stator and rotor under different test currents.

[0127] Step S153, based on the second motor parameters corresponding to the test current, determine the target rotor resistance and target slip corresponding to the test current when the output torque of the asynchronous motor is the maximum torque and the electrical angular velocity and electrical angle output by the flux current model and the dq-axis current model of the asynchronous motor are the same.

[0128] In some embodiments, the observation formulas of the flux current model of the asynchronous motor are as follows (14) and (15):

[0129]

[0130] Among them, L r is the rotor inductance, Rr is the steady-state rotor resistance, L m is the magnetizing inductance, i sα is the α-axis current, i sβ is the β-axis current, Ψ rα is the rotor magnetic field orientation α-axis flux, Ψ rβ is the rotor magnetic field oriented β-axis flux, τ r is the time constant, ω r is the angular velocity of the rotation transformer, and p is the differential operator.

[0131] From the above formula (14), it can be known that the rotor magnetic field orientation α-axis flux Ψ rα and rotor oriented β-axis flux Ψ rβ The acquisition of is affected by the parameters of the asynchronous motor. r With the excitation inductance L m The influence of current and temperature is small, but the rotor resistance Rr is greatly affected by the rotor temperature, which will affect Ψ rα With rβ Based on the rotor magnetic field orientation α-axis flux Ψ rα and rotor oriented β-axis flux Ψ rβ , the control angle θ of the asynchronous motor can be obtained by using a phase-locked loop im and electrical angular velocity ω im .

[0132] The equations of the dq axis current model of the asynchronous motor are as follows (16) to (20):

[0133] i d =I s *cos(θ); (16)

[0134] i q =I s *sin(θ); (17)

[0135] ω f =Rr*i q / (L r *i d ); (18)

[0136] θ im =∑(ω r +ω f )*T s ; (19)

[0137]

[0138] Among them, i d is the direct axis current, i q is the quadrature axis current, I s is the current vector, θ is the torque angle, ω f is the slip, Rr is the steady-state rotor resistance, L r is the rotor inductance, θ im To control the angle, ω r is the angular velocity of the resolver, T s is the control period, T e is the torque, p0 is the number of pole pairs of the asynchronous motor, L m is the magnetizing inductance, τ r is the time constant.

[0139] From the above formulas (16) and (17), it can be seen that under the condition that the current vector Is is constant, different direct-axis currents i can be obtained according to the given torque angle θ. d and the quadrature axis current i q From formula (18), we can know that the slip ω f The magnitude of the direct axis current i d , quadrature axis current i q , rotor resistance Rr and rotor inductance L r The direct axis current i d and the quadrature axis current i q Under certain conditions, the rotor inductance L r The rotor resistance is basically unchanged under the influence of current and temperature. The rotor resistance is greatly affected by temperature, and the change of rotor resistance will cause slip ω f From formula (19), we can know that the control angle θ of the asynchronous motor im and the resolver angular velocity ω r , slip ω f Strong correlation, resolver angular velocity ω r The signal is obtained by hardware detection, and the error is very small, so the control angle θ im The accuracy and precision of f Influence. From formula (20), we can know that the current vector I s The size of is constant, the slip ω f The magnitude of the torque T is constant. e The size is certain.

[0140] Through the theoretical derivation of the above formula, it can be seen that the torque T of the asynchronous motor e Size accuracy, control angle θ im The accuracy is related to the slip ω f is strongly correlated with the motor parameters. f The rotor resistance is affected by the rotor temperature, so the accurate acquisition of dynamic rotor resistance is very important for the control accuracy and dynamic response of asynchronous motor.

[0141] Figure 6 FIG. 1 is a schematic diagram of verifying a dq axis current model and a magnetic flux current model provided by an embodiment of the present invention, such as Figure 6 As shown, the input parameters of the dq axis current model include the current vector I s 、Resolver angular velocity ω r and slip ω f , the output parameters include electrical angular velocity (target slip ω f0 + Rotor angular velocityω r ) and electrical angle θ1; the input parameters of the flux current model include the α-axis current isα , β-axis current is i sβ , steady-state rotor resistance Rr, excitation inductance L m , rotor inductance L r and the angular velocity ω r , the output parameters include electrical angular velocity ω c and electrical angle θ2.

[0142] In some embodiments, step S153 may include:

[0143] Load the asynchronous motor with the first test current I0 (which can be a small current, for example, I0=Is1), and give a torque angle θx=θx1 (for example, 45°, so that the output torque of the asynchronous motor is close to the maximum torque), and determine the initial slip of the test asynchronous motor; adjust the initial slip until the output torque of the asynchronous motor is maintained at the maximum torque Tmax1, so as to obtain the target slip corresponding to the first test current; take the sum of the target slip and the rotary angular velocity of the asynchronous motor as the electrical angular velocity output by the dq-axis current model; adjust the steady-state rotor resistance Rr in the magnetic flux current model until the electrical angular velocity and electrical angle output by the magnetic flux current model and the dq-axis current model are the same, so as to obtain the first target rotor resistance Rrx1 corresponding to the first test current Is1. Among them, the excitation inductance L calibrated in step S120 can be m , rotor inductance L r The second motor parameters are used as the input parameters of the flux current model. According to formulas (16) and (17), the direct axis current id and quadrature axis current i corresponding to the first test current I0 can be obtained respectively. q According to the determined direct axis current id and quadrature axis current i q , the excitation inductance calibrated in step S120, the steady-state rotor resistance calibrated in step S140, and formula (18) can be used to obtain the initial slip corresponding to the first test current I0.

[0144] By adjusting the test current I0 to a larger or smaller value multiple times and repeating the above process, the target rotor resistance and target slip corresponding to the multiple test currents can be determined.

[0145] Step S154, based on the target rotor resistance and the target slip corresponding to the test current, determine the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current.

[0146] In some embodiments, step S154 may include:

[0147] The first step is to obtain the initial rotor temperature Tr1' and the initial stator temperature Ts1' (approximately equal to the laboratory temperature) when the asynchronous motor is not loaded with current and the motor is dragged;

[0148] Step 2: Determine the initial rotor resistance Rr1 corresponding to the initial rotor temperature Tr1' according to the following formula (21):

[0149] Rr1=Rr0*(1+Kr0*(Tr1'-T0)); (21)

[0150] Wherein, Rr0 is the reference rotor resistance of the asynchronous motor measured in advance at the test temperature T0, and Kr0 is the temperature coefficient of the rotor material;

[0151] Step 3: Load the asynchronous motor with the first test current I0=Is1, set the motor slip as the target slip, record the stator temperature Ts2 and the temperature rise time ts1 when the stator temperature reaches stability, and record the temperature rise time tr1 when the output torque of the asynchronous motor reaches the maximum torque Tmax1. The temperature rise time tr1 is the rotor temperature rise time.

[0152] Step 4: Determine the rotor temperature Tr2 after the temperature rise time tr1 according to the following formula (22):

[0153] Tr2=(Rrx1 / Rr1-1) / Kr0+Tr1'; (22)

[0154] Among them, Rrx1 is the first target rotor resistance Rrx1 corresponding to the first test current I0, which can be determined according to step S153; Rr1 is the initial rotor resistance Rr1 corresponding to the initial rotor temperature Tr1'.

[0155] Step 5: Determine the rotor temperature rise slope Coff_r1 corresponding to the first test current Is1 according to the following formula (23):

[0156] Coff_r1=(Tr2-Tr1') / tr1; (23)

[0157] The stator temperature rise slope Coff_s1 corresponding to the first test current Is1 is determined according to the following formula (24):

[0158] Coff_s1=(Ts2-Ts1') / ts1; (24)

[0159] Adjust the test current I0 to a larger or smaller value multiple times, and repeat steps 3 to 5 to determine the rotor temperature rise slope Coff_rx and the stator temperature rise slope Coff_sx corresponding to the multiple test currents.

[0160] Figure 7 Schematic diagram of the rotor temperature change and the stator temperature change under different test currents provided by the embodiment of the present invention, such as Figure 7As shown, in the actual operation of the asynchronous motor, under the conditions of high current or high torque rapid acceleration, the stator temperature rises rapidly, while the rotor temperature changes very slowly; under the conditions of low current or low torque stable operation, the stator temperature changes slowly, and the rotor temperature also changes slowly. Therefore, the mapping relationship between the rotor temperature and the stator temperature of the asynchronous motor in steady state obtained in step S152 is not reasonable enough. The embodiment of the present application calibrates the temperature change ratio between the rotor temperature change rate and the stator temperature change rate by giving different current vector sizes to achieve dynamic calibration of the rotor resistance, and the calibration result is more accurate.

[0161] Step S155, determining the temperature rise rate ratio of the stator and rotor corresponding to the test current based on the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current.

[0162] In some embodiments, the temperature rise rate ratio ζx of the stator and rotor corresponding to the test current can be determined according to the following formula (25):

[0163] ζx=Coff_rx / Coff_sx; (25)

[0164] Among them, Coff_rx is the rotor temperature rise slope corresponding to the test current, and Coff_sx is the stator temperature rise slope corresponding to the test current.

[0165] Under different currents, the temperature ratio of the steady-state rotor temperature to the stator temperature is: ηx = Trx / Tsx. Under different current conditions, the temperature rise rate ratio of the dynamic stator and rotor temperature is: ζx = Coff_rx / Coff_sx, which can form a complete relationship between the temperature rise rate ratio ζx and the stator temperature and current.

[0166] Step S156, based on the stator temperature corresponding to the test current, the temperature mapping relationship and the temperature rise rate ratio, calibrate the dynamic rotor resistance corresponding to the test current in each control cycle of the asynchronous motor.

[0167] In some embodiments, the conventional rotor resistance calculation formula (26) is as follows:

[0168] Rr=[Kr0*(Trx-Tr0)+1]*Rr0; (26)

[0169] Combining formula (13) and formula (25), the above formula (26) can be transformed to obtain formula (27):

[0170] Rrb=[Kr0*ζx*(ηx*Tsx-η1*Ts1)+1]*Rra; (27)

[0171] In step S156, the dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor can be calculated according to the above formula (27). Among them, η1, Ts1 and Rra are the temperature mapping relationship, stator temperature and dynamic rotor resistance corresponding to the test current in the previous control cycle of the asynchronous motor; ηx, Tsx, ζx and Rrb are the temperature mapping relationship, stator temperature, temperature rise rate ratio and dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor; Kr0 is the rotor material temperature coefficient. Based on the above formula (27), the dynamic rotor resistance can be calculated by different stator temperatures, and the optimal rotor resistance can be obtained by continuous iteration.

[0172] The above steps can complete the calibration of the key parameters of the asynchronous motor (including stator resistance, stator leakage inductance, stator inductance, rotor leakage inductance, rotor resistance, rotor inductance and excitation inductance), and the calibrated parameters can meet the requirements of accurate identification of the steady-state and dynamic conditions of the motor under different currents and temperatures.

[0173] Based on the same inventive concept, an embodiment of the present invention further provides a parameter calibration device for an asynchronous motor, which is used to obtain multiple test currents, and for each test current, perform a parameter calibration operation on the asynchronous motor based on the test current. Figure 8 is a structural block diagram of a parameter calibration device for an asynchronous motor provided by an embodiment of the present invention, such as Figure 8 As shown, the device 800 includes:

[0174] A first calibration module 810, configured to perform a stall test on the asynchronous motor, and calibrate first motor parameters corresponding to the test current based on stall test parameters corresponding to the test current, the first motor parameters at least including stator leakage inductance and rotor leakage inductance;

[0175] A second calibration module 820, for performing a no-load test on the asynchronous motor, and calibrating second motor parameters corresponding to the test current based on the no-load test parameters corresponding to the test current and the first motor parameters, the second motor parameters at least including the excitation inductance, the stator inductance and the rotor inductance;

[0176] A third calibration module 830 is used to obtain a stator temperature corresponding to the test current, and calibrate a stator resistance corresponding to the test current based on the stator temperature corresponding to the test current;

[0177] A fourth calibration module 840, configured to calibrate a steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter, and the locked-rotor test parameter;

[0178] The fifth calibration module 850 is used to calibrate the dynamic rotor resistance corresponding to the test current based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter and the second motor parameter.

[0179] Parameter calibration operation can be realized through the above five calibration modules.

[0180] Optionally, the third calibration module 830 is further used for:

[0181] According to the following relationship between stator temperature and stator resistance, calibrate the stator resistance corresponding to the test current:

[0182] Rs1 = Rs0*(1+Ks0*(Ts1-T0));

[0183] Among them, Rs1 is the stator resistance, Rs0 is the pre-measured reference stator resistance of the asynchronous motor at the test temperature T0, Ks0 is the stator material temperature coefficient, and Ts1 is the stator temperature.

[0184] Optionally, the locked rotor test parameters include at least a locked rotor current, a locked rotor voltage and a first power factor corresponding to the test current. The first calibration module 810 is also used for:

[0185] The first motor parameter corresponding to the test current is calibrated based on the following formula:

[0186]

[0187] Among them, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, φ1 is the first power factor, f el For a given frequency.

[0188] Optionally, the no-load test parameters include at least the no-load current, no-load voltage and second power factor corresponding to the test current. The second calibration module 810 is also used for:

[0189] The second motor parameters corresponding to the test current are calibrated based on the following formula:

[0190]

[0191] L s =L m +L ls ;

[0192] L r =L m +L lr ;

[0193] Among them, L m is the excitation inductance, I2 is the no-load current, U2 is the no-load voltage, φ2 is the second power factor, f el For a given frequency, L Is is the stator leakage inductance, L s is the stator inductance, Lr is the rotor inductance, L Ir is the rotor leakage inductance.

[0194] Optionally, the fourth calibration module 840 is further used for:

[0195] The steady-state rotor resistance corresponding to the test current is calibrated based on the following formula:

[0196]

[0197] Among them, Rr is the steady-state rotor resistance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, and f el For a given frequency, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance and Rs is the stator resistance.

[0198] Optionally, the fifth calibration module is further used for:

[0199] Based on the steady-state rotor resistance corresponding to the test current, determine the rotor temperature corresponding to the test current;

[0200] Based on the rotor temperature and the stator temperature corresponding to the test current, determining a temperature mapping relationship between the rotor temperature and the stator temperature corresponding to the test current;

[0201] Based on the second motor parameter corresponding to the test current, determine the target rotor resistance and target slip corresponding to the test current when the output torque of the asynchronous motor is the maximum torque and the electrical angular velocity and electrical angle output by the magnetic flux current model and the dq-axis current model of the asynchronous motor are the same;

[0202] Based on the target rotor resistance and target slip corresponding to the test current, determine the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current;

[0203] Based on the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current, determine the stator and rotor temperature rise rate ratio corresponding to the test current;

[0204] Based on the stator temperature corresponding to the test current, the temperature mapping relationship and the temperature rise rate ratio, the dynamic rotor resistance corresponding to the test current in each control cycle of the asynchronous motor is calibrated.

[0205] Optionally, the fifth calibration module is further used for:

[0206] The dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor is calibrated based on the following formula:

[0207] Rrb=[Kr0*ζx*(ηx*Tsx-η1*Ts1)+1]*Rra;

[0208] Among them, η1, Ts1 and Rra are the temperature mapping relationship, stator temperature and dynamic rotor resistance corresponding to the test current in the previous control cycle of the asynchronous motor respectively; ηx, Tsx, ζx and Rrb are the temperature mapping relationship, stator temperature, temperature rise rate ratio and dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor respectively; Kr0 is the temperature coefficient of the rotor material.

[0209] The specific details of the parameter calibration method used in the above-mentioned parameter calibration device can be understood by referring to the corresponding related descriptions and effects in the above-mentioned parameter calibration method embodiment, and will not be repeated here.

[0210] Based on the same inventive concept as the above-mentioned parameter calibration method, the present invention also provides an electronic device, which may include a processor and a memory, wherein the processor and the memory may be connected to each other by bus or other means. The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components and other chips, or a combination of the above-mentioned various types of chips. The memory, as a non-transient computer-readable storage medium, may be used to store non-transient software programs, non-transient computer executable programs and modules, such as program instructions / modules corresponding to the parameter calibration method in the embodiment of the present invention. The processor executes various functional applications and data processing of the processor by running the non-transient software programs, instructions and modules stored in the memory, that is, to realize the parameter calibration of the asynchronous motor in the above-mentioned method embodiment.

[0211] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system and an application required by at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. The one or more modules are stored in the memory, and when executed by the processor, the execution is as follows: Figure 1 The parameter calibration method in the illustrated embodiment.

[0212] For details of the above electronic equipment, please refer to Figure 1The corresponding related descriptions and effects in the illustrated embodiments can be understood and will not be repeated here.

[0213] Based on the same inventive concept as the parameter calibration method, the present invention also provides a computer-readable storage medium, on which computer instructions are stored, and the computer program instructions are used to enable a computer to execute the parameter calibration method in the above embodiment.

[0214] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium can be a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD), etc.; the storage medium can also include a combination of the above-mentioned types of memory.

[0215] The technical solutions provided in the above embodiments of the present application have at least the following technical effects or advantages:

[0216] The present invention provides a method, device, equipment and storage medium for calibrating parameters of an asynchronous motor. The asynchronous motor is subjected to a stall test and a no-load test to obtain relevant test parameters of the asynchronous motor under a plurality of test currents when the rotor is stalled or the motor is no-loaded. On the one hand, since the current of the motor is very large under the stall condition, the influence of the leakage inductance becomes significant. Therefore, the stator and rotor leakage inductance can be more accurately calibrated through the stall test parameters. On the other hand, since the rotor current is very small under the no-load condition, the influence of the rotor resistance and leakage inductance can be ignored. Therefore, the excitation inductance and the stator and rotor inductance can be more accurately calibrated through the no-load test parameters. The parameter calibration method of the present application not only takes into account the influence of the current on each motor parameter, but also takes into account the influence of the motor temperature change on each motor parameter, associates the stator resistance with the stator temperature, and according to the relationship between the motor parameters, respectively calibrates the stator and rotor leakage inductance, inductance, resistance and excitation inductance when the motor produces temperature changes under different test currents, thereby meeting the precise calibration requirements of the motor parameters under different currents and temperatures. At the same time, when calibrating the motor rotor resistance, not only the steady-state rotor resistance of the motor in steady-state conditions is calibrated, but also the influence of the stator temperature change on the rotor resistance under dynamic conditions is considered, and the rotor resistance is associated with the stator temperature to further calibrate the dynamic rotor resistance of the motor in dynamic conditions. The efficient and reliable calibration method formed by this scheme can not only ensure the accuracy of the parameters of the asynchronous motor, improve the accuracy and stability of the asynchronous motor control, but also improve the accuracy and precision of the control angle and output torque of the asynchronous motor in the subsequent operation process, improve the dynamic responsiveness of the asynchronous motor, reduce the risk of control divergence, and prevent the motor from running in under-excitation and over-excitation states, reducing the risk of overheating of the motor.

[0217] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0218] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those explicitly recited in each claim. More specifically, as reflected in the claims below, inventive aspects lie in less than all the features of the individual embodiments disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present invention.

[0219] It should be noted that the above-mentioned embodiments illustrate rather than limit the invention and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims.

Claims

1. A method for calibrating parameters of an asynchronous motor, characterized in that: The parameter calibration method comprises: A plurality of test currents are obtained, and for each test current, a parameter calibration operation is performed on the asynchronous motor based on the test current, wherein the parameter calibration operation includes: Performing a stall test on the asynchronous motor, and calibrating a first motor parameter corresponding to the test current based on a stall test parameter corresponding to the test current, wherein the first motor parameter includes at least a stator leakage inductance and a rotor leakage inductance; Performing a no-load test on the asynchronous motor, and calibrating a second motor parameter corresponding to the test current based on a no-load test parameter corresponding to the test current and the first motor parameter, wherein the second motor parameter includes at least a magnetizing inductance, a stator inductance, and a rotor inductance; Acquire the stator temperature corresponding to the test current, and calibrate the stator resistance corresponding to the test current based on the stator temperature corresponding to the test current; Calibrate the steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter and the locked-rotor test parameter; The dynamic rotor resistance corresponding to the test current is calibrated based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter, and the second motor parameter.

2. The method according to claim 1, characterized in that The step of calibrating the stator resistance corresponding to the test current based on the stator temperature corresponding to the test current includes: According to the following relationship between stator temperature and stator resistance, calibrate the stator resistance corresponding to the test current: Rs=Rs0*(1+Ks0*(Ts1-T0)); Wherein, Rs is the stator resistance, Rs0 is the pre-measured reference stator resistance of the asynchronous motor at the test temperature T0, Ks0 is the stator material temperature coefficient, and Ts1 is the stator temperature.

3. The method according to claim 1, characterized in that The locked-rotor test parameters at least include a locked-rotor current, a locked-rotor voltage and a first power factor corresponding to the test current; The step of calibrating the first motor parameter corresponding to the test current based on the locked-rotor test parameter corresponding to the test current includes: The first motor parameter corresponding to the test current is calibrated based on the following formula: Among them, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, φ1 is the first power factor, f el For a given frequency.

4. The method according to claim 3, characterized in that The no-load test parameters include at least the no-load current, no-load voltage and second power factor corresponding to the test current; The step of calibrating the second motor parameter corresponding to the test current based on the no-load test parameter corresponding to the test current and the first motor parameter includes: The second motor parameter corresponding to the test current is calibrated based on the following formula: L s =L m +L ls ; L r =L m +L lr ; Among them, L m is the excitation inductance, I2 is the no-load current, U2 is the no-load voltage, φ2 is the second power factor, f el For the given frequency, L Is is the stator leakage inductance, L s is the stator inductance, L r is the rotor inductance, L Ir is the rotor leakage inductance.

5. The method according to claim 3, characterized in that: The step of calibrating the steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter, and the locked-rotor test parameter comprises: The steady-state rotor resistance corresponding to the test current is calibrated based on the following formula: Wherein, Rr is the steady-state rotor resistance, I1 is the locked-rotor current, U1 is the locked-rotor voltage, and f el For a given frequency, L Is is the stator leakage inductance, L Ir is the rotor leakage inductance and Rs is the stator resistance.

6. The method according to claim 1, characterized in that The step of calibrating the dynamic rotor resistance corresponding to the test current based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter, and the second motor parameter includes: Determining a rotor temperature corresponding to the test current based on the steady-state rotor resistance corresponding to the test current; Based on the rotor temperature and the stator temperature corresponding to the test current, determining a temperature mapping relationship between the rotor temperature and the stator temperature corresponding to the test current; Based on the second motor parameter corresponding to the test current, determine the target rotor resistance and target slip corresponding to the test current when the output torque of the asynchronous motor is the maximum torque and the electrical angular velocity and electrical angle output by the magnetic flux current model and the dq-axis current model of the asynchronous motor are the same; Based on the target rotor resistance and target slip corresponding to the test current, determining the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current; Determine the temperature rise rate ratio of the stator and rotor corresponding to the test current based on the rotor temperature rise slope and the stator temperature rise slope corresponding to the test current; Based on the stator temperature corresponding to the test current, the temperature mapping relationship and the temperature rise rate ratio, the dynamic rotor resistance corresponding to the test current in each control cycle of the asynchronous motor is calibrated.

7. The method according to claim 6, characterized in that The dynamic rotor resistance corresponding to the test current is calibrated in each control cycle of the asynchronous motor based on the stator temperature corresponding to the test current, the temperature mapping relationship and the temperature rise rate ratio, including: The dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor is calibrated based on the following formula: Rrb=[Kr0*ζx*(ηx*Tsx-η1*Ts1)+1]*Rra; Among them, η1, Ts1 and Rra are respectively the temperature mapping relationship, the stator temperature and the dynamic rotor resistance corresponding to the test current in the previous control cycle of the asynchronous motor; ηx, Tsx, ζx and Rrb are respectively the temperature mapping relationship, the stator temperature, the temperature rise rate ratio and the dynamic rotor resistance corresponding to the test current in the current control cycle of the asynchronous motor; Kr0 is the temperature coefficient of the rotor material.

8. A parameter calibration device for an asynchronous motor, characterized in that: The parameter calibration device is used to obtain multiple test currents, and for each test current, a parameter calibration operation is performed on the asynchronous motor based on the test current. The parameter calibration device includes: A first calibration module, used for performing a stall test on the asynchronous motor, and calibrating a first motor parameter corresponding to the test current based on a stall test parameter corresponding to the test current, wherein the first motor parameter includes at least a stator leakage inductance and a rotor leakage inductance; A second calibration module, used for performing a no-load test on the asynchronous motor, and calibrating a second motor parameter corresponding to the test current based on the no-load test parameter corresponding to the test current and the first motor parameter, wherein the second motor parameter includes at least an excitation inductance, a stator inductance, and a rotor inductance; A third calibration module, used for obtaining a stator temperature corresponding to the test current, and calibrating a stator resistance corresponding to the test current based on the stator temperature corresponding to the test current; a fourth calibration module, configured to calibrate a steady-state rotor resistance corresponding to the test current based on the stator resistance corresponding to the test current, the first motor parameter, and the locked-rotor test parameter; A fifth calibration module is used to calibrate the dynamic rotor resistance corresponding to the test current based on the steady-state rotor resistance corresponding to the test current, the stator temperature, the first motor parameter and the second motor parameter.

9. An electronic device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the parameter calibration method according to any one of claims 1 to 7 by executing the computer instructions.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable the computer to execute the parameter calibration method according to any one of claims 1 to 7.

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