Motor parameter identification method and device

Abstract

Disclosed are a motor parameter identification method and device, comprising: controlling the motor to operate in a speed closed loop and current closed loop mode according to a reference model of the motor, and obtaining direct-axis voltage, cross-axis voltage, direct-axis current, cross-axis current and motor speed; obtaining direct-axis estimated current and cross-axis estimated current according to an adjustable model of the motor, the direct-axis voltage and the cross-axis voltage; obtaining direct-axis error current according to the direct-axis current and the direct-axis estimated current, and obtaining cross-axis error current according to the cross-axis current and the cross-axis estimated current; adjusting the direct-axis estimated inductance and the cross-axis estimated inductance in the adjustable model through feedback of an adaptive rate model, so that the direct-axis error current and the cross-axis error current converge; the adaptive rate model and the adjustable model adopt a salient pole ratio of the motor. The salient pole ratio of the motor is introduced in the application, the direct-axis inductance parameter and the cross-axis inductance parameter are decoupled and processed, direct coupling of the direct-axis inductance estimated value and the cross-axis inductance estimated value is avoided, and the adaptive rate model is simplified.

Description

Technical Field

[0001] This invention relates to the field of motor control technology, and in particular to a method and apparatus for identifying motor parameters. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) have advantages such as high power density, wide speed range, high efficiency, small size, fast response and reliable operation, and are widely used in AC drive applications such as home appliances, CNC machine tools, industrial robots, electric vehicles and aerospace equipment.

[0003] The design of a motor control system requires precise acquisition of key parameters such as stator winding resistance, stator winding AC and DC axis inductance, and permanent magnet flux linkage.

[0004] In high-performance PMSM control systems, parameter accuracy is a crucial factor affecting the overall system control precision, especially key parameters such as stator winding resistance, direct-axis and quadrature-axis inductance, permanent magnet flux linkage, and moment of inertia. Because the PMSM control drive system is a nonlinear, multivariable, and time-varying system, these parameters fluctuate under actual operating conditions due to environmental temperature, magnetic saturation, and load disturbances. The moment of inertia also varies with the size and shape of the mechanical load. Any change in these parameters will affect the system's operating state. To achieve high-performance control of the permanent magnet synchronous motor, online identification of motor parameters is necessary during motor operation.

[0005] Commonly used permanent magnet synchronous motors are mainly surface-mounted permanent magnet synchronous motors and internal permanent magnet synchronous motors. The quadrature axis inductance parameter of the internal permanent magnet synchronous motor is greater than that of the direct axis inductance parameter, which makes the permanent magnet synchronous motor exhibit a more obvious salient pole effect, thereby improving its power output range and speed regulation range. However, the coupling between the direct axis and the quadrature axis is more complex, making it difficult to identify the inductance parameter.

[0006] Existing model-based motor parameter identification algorithms include the Model Reference Adaptive System (MRAS). MRAS is simple to implement, has strong resistance to external interference, and exhibits good steady-state accuracy and dynamic performance, especially during the high-speed phase of stable motor operation. When using the MRAS algorithm for speed and position estimation in a PMSM, the estimated speed and rotor position only converge to the corresponding actual values ​​when the difference between the outputs of the reference model and the adjustable model converges to zero. The setting of the adaptive rate of the internal adaptive mechanism (PI controller) of the MRAS is also a crucial part of the algorithm. The direct-axis inductance parameter L of the built-in permanent magnet synchronous motor... d and quadrature axis inductance parameter Lq The differences are significant; the coupling effect between the direct axis and the quadrature axis will affect the direct axis inductance parameter L during the adaptive rate derivation process. d and quadrature axis inductance parameter L q The inductance parameters cannot be separated, and its adaptive rate cannot be determined, thus increasing the difficulty of identifying the inductance parameters. Summary of the Invention

[0007] In view of the above problems, the purpose of this invention is to provide a method and apparatus for motor parameter identification, which decouples the direct-axis inductance parameters and quadrature-axis inductance parameters in the inductance identification process. When identifying the direct-axis and quadrature-axis inductances, the salient pole ratio of the motor is introduced, so that the calculation of the quadrature-axis inductance estimate does not involve the estimate of the direct-axis inductance in the adaptive rate design process, which greatly reduces the design difficulty of the adaptive rate and avoids the direct coupling of the direct-axis inductance estimate and the quadrature-axis inductance estimate in the calculation process, thereby realizing online identification of motor inductance parameters.

[0008] According to a first aspect of the present invention, a method for identifying motor parameters is provided, comprising: controlling the motor to operate in a speed closed-loop and current closed-loop mode according to a reference model of the motor, and acquiring the direct-axis voltage, quadrature-axis voltage, direct-axis current, quadrature-axis current and motor speed of the motor; acquiring the estimated direct-axis current and estimated quadrature-axis current of the motor according to an adjustable model of the motor, the direct-axis voltage and the quadrature-axis voltage of the motor; acquiring the direct-axis error current according to the direct-axis current and the estimated direct-axis current, and acquiring the quadrature-axis error current according to the quadrature-axis current and the estimated quadrature-axis current; adjusting the estimated direct-axis inductance and the estimated quadrature-axis inductance in the adjustable model through the feedback of an adaptive rate model, so that the direct-axis error current and the quadrature-axis error current converge, to obtain the direct-axis inductance parameters and the quadrature-axis inductance parameters that satisfy a first preset condition and a second preset condition; wherein the adaptive rate model and the adjustable model adopt the salient pole ratio of the motor.

[0009] Preferably, the salient pole ratio is the ratio of quadrature-axis inductance to direct-axis inductance.

[0010] Preferably, the first preset condition is that the direct-axis error current is less than 30% of the direct-axis current, and the quadrature-axis error current is less than 30% of the quadrature-axis current; the second preset condition is that the direct-axis error current is not greater than 10% of the direct-axis current, and the quadrature-axis error current is not greater than 10% of the quadrature-axis current.

[0011] Preferably, adjusting the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model through the feedback of the adaptive rate model to make the direct-axis error current and quadrature-axis error current converge includes: determining whether the direct-axis error current and quadrature-axis error current meet a first preset condition; if the direct-axis error current and quadrature-axis error current do not meet the first preset condition, then inputting the current direct-axis current and quadrature-axis current as the direct-axis estimated current and quadrature-axis estimated current into the adjustable model for iterative calculation of the next time step's direct-axis estimated current and quadrature-axis estimated current until the direct-axis error current and quadrature-axis error current meet the first preset condition.

[0012] Preferably, adjusting the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model through the feedback of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, further includes: if the direct-axis error current and quadrature-axis error current meet the first preset condition, obtaining the direct-axis estimated inductance and quadrature-axis estimated inductance at the current moment based on the current direct-axis voltage, quadrature-axis voltage, direct-axis estimated current, quadrature-axis estimated current, direct-axis error current, quadrature-axis error current, motor salient pole ratio, and the adaptive rate model.

[0013] Preferably, adjusting the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model through the feedback of the adaptive rate model to make the direct-axis error current and quadrature-axis error current converge further includes: determining whether the direct-axis error current and quadrature-axis error current meet a second preset condition; if the direct-axis error current and quadrature-axis error current do not meet the second preset condition, inputting the current direct-axis estimated inductance and quadrature-axis estimated inductance into the adjustable model for iterative calculation of the next time-to-time direct-axis estimated current and quadrature-axis estimated current until the direct-axis error current and quadrature-axis error current meet the second preset condition.

[0014] Preferably, adjusting the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model through the feedback of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, further includes: if the direct-axis error current and quadrature-axis error current meet the second preset condition, then the output of the current direct-axis estimated inductance and quadrature-axis estimated inductance is used as the direct-axis inductance and quadrature-axis inductance of the motor.

[0015] Preferably, the first preset condition is |e d (k)<i d (k)*30%|, and |e q (k)<i q (k)*30%|;The second preset condition is|e d (k)≤i d (k)*10%|, and |e q (k)≤i q (k)*10%|, where ed (k) represents the direct-axis error current at the current moment, i d (k) represents the direct-axis current at the current moment; e q (k) represents the quadrature axis error current at the current moment, i q (k) represents the quadrature-axis current at the current moment.

[0016] Preferably, the function of the reference model is:

[0017]

[0018] Where id is the direct-axis current, iq is the quadrature-axis current, ud is the direct-axis voltage, uq is the quadrature-axis voltage, w is the rotational speed, R is the stator resistance, Ld is the direct-axis inductance, Lq is the quadrature-axis inductance, and ψ is the quadrature-axis inductance. f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0019] Preferably, the function discretization formula of the adjustable model is:

[0020]

[0021] Where k is a positive integer, Estimate the current along the direct axis at the current moment; Estimate the current along the quadrature axis at the current moment; Estimate the direct-axis current for the previous moment; Estimate the current for the quadrature axis at the previous moment; u d (k-1) is the direct-axis voltage at the previous moment, u d (k-1) represents the quadrature-axis voltage at the previous moment, and w(k-1) represents the rotational speed at the previous moment. Estimate the inductance along the direct axis from the previous time step. The quadrature-axis inductance is estimated for the previous moment, where ρ is the salient pole ratio of the motor.

[0022] Preferably, the initial values ​​of the direct-axis estimated inductance and the quadrature-axis estimated inductance are any positive integers.

[0023] Preferably, the function of the adaptive rate model is:

[0024]

[0025]

[0026] Where kp and ki are the regulator ratio and integral factor in the adaptive rate model, respectively, Ts is the sampling time, and z is the complex variable in the discretized z-transform. Estimate the direct-axis current at the current moment. Let ed(k) be the quadrature-axis current estimate at the current moment, eq(k) be the direct-axis current error at the current moment, ud(k) be the direct-axis voltage at the current moment, uq(k) be the quadrature-axis voltage at the current moment, w(k) be the rotational speed at the current moment, and R be the stator resistance. Estimate the inductance along the direct axis at the current moment. Estimate the inductance for the quadrature axis at the current moment, ψ f ρ is the flux linkage generated in the stator winding by the fundamental magnetic field, and ρ is the salient pole ratio of the motor.

[0027] According to another aspect of the present invention, a motor parameter identification device is provided, comprising: a vector control module, configured to construct a reference model of the motor, control the motor to operate in a speed closed-loop and current closed-loop control mode, and acquire the direct-axis voltage, quadrature-axis voltage, direct-axis current, quadrature-axis current and motor speed of the motor; an inductance identification module, configured to construct an adjustable model and an adaptive rate model of the motor, acquire the direct-axis estimated current and quadrature-axis estimated current of the motor based on the direct-axis voltage and quadrature-axis voltage of the motor; acquire the direct-axis error current based on the direct-axis current of the reference model and the direct-axis estimated current of the adjustable model, and acquire the quadrature-axis error current based on the quadrature-axis current of the reference model and the quadrature-axis estimated current of the adjustable model; and adjust the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model through the feedback of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, to acquire direct-axis inductance parameters and quadrature-axis inductance parameters that satisfy a first preset condition and a second preset condition; wherein the adaptive rate model and the adjustable model adopt the salient pole ratio of the motor.

[0028] Preferably, the salient pole ratio is the ratio of quadrature-axis inductance to direct-axis inductance.

[0029] Preferably, the first preset condition is that the direct-axis error current is less than 30% of the direct-axis current, and the quadrature-axis error current is less than 30% of the quadrature-axis current; the second preset condition is that the direct-axis error current is not greater than 10% of the direct-axis current, and the quadrature-axis error current is not greater than 10% of the quadrature-axis current.

[0030] Preferably, the inductance identification module includes: an adjustable model unit, used to obtain the estimated direct-axis current and estimated quadrature-axis current of the motor based on the direct-axis voltage and quadrature-axis voltage of the motor; an adaptive rate model unit, used to obtain the quadrature-axis error current based on the quadrature-axis current of the reference model and the quadrature-axis estimated current of the adjustable model; and to adjust the estimated direct-axis inductance and estimated quadrature-axis inductance in the adjustable model through the feedback of the adaptive rate model, so that the direct-axis error current and the quadrature-axis error current converge, so as to obtain the direct-axis inductance parameters and quadrature-axis inductance parameters that satisfy the first preset condition and the second preset condition, wherein the adaptive rate model and the adjustable model adopt the salient pole ratio of the motor.

[0031] Preferably, the inductor identification module further includes: a first judgment unit, used to judge whether the direct-axis error current and the quadrature-axis error current meet a first preset condition; the adjustable model unit is further used to, if the direct-axis error current and the quadrature-axis error current do not meet the first preset condition, input the current direct-axis current and the quadrature-axis current as the estimated direct-axis current and the estimated quadrature-axis current into the adjustable model for iterative calculation of the estimated direct-axis current and the estimated quadrature-axis current at the next moment until the direct-axis error current and the quadrature-axis error current meet the first preset condition.

[0032] Preferably, the adaptive rate model unit is further configured to, if the direct-axis error current and quadrature-axis error current satisfy the first preset condition, obtain the current-time direct-axis estimated inductance and quadrature-axis estimated inductance based on the current-time direct-axis voltage, quadrature-axis voltage, direct-axis estimated current, quadrature-axis estimated current, direct-axis error current, quadrature-axis error current, motor salient pole ratio, and adaptive rate model.

[0033] Preferably, the inductance identification module further includes: a second judgment unit, used to judge whether the direct-axis error current and the quadrature-axis error current meet a second preset condition; the adaptive rate model unit is further used to input the current-time estimated direct-axis inductance and quadrature-axis estimated inductance into an adjustable model for iterative calculation of the next-time estimated direct-axis current and quadrature-axis estimated current until the direct-axis error current and quadrature-axis error current meet the second preset condition if the current-time and quadrature-axis error current do not meet the second preset condition.

[0034] Preferably, the adaptive rate model unit is further configured to output the current estimated direct-axis inductance and quadrature-axis inductance as the motor's direct-axis inductance and quadrature-axis inductance if the direct-axis error current and quadrature-axis error current satisfy the second preset condition.

[0035] Preferably, the first preset condition is |e d (k)<i d (k)*30%|, and |e q (k)<i q (k)*30%|;The second preset condition is|e d (k)≤i d (k)*10%|, and |e q (k)≤i q (k)*10%|, where e d (k) represents the direct-axis error current at the current moment, i d (k) represents the direct-axis current at the current moment; e q (k) represents the quadrature axis error current at the current moment, i q (k) represents the quadrature-axis current at the current moment.

[0036] Preferably, the function of the reference model is:

[0037]

[0038] Where id is the direct-axis current, iq is the quadrature-axis current, ud is the direct-axis voltage, uq is the quadrature-axis voltage, w is the rotational speed, R is the stator resistance, Ld is the direct-axis inductance, Lq is the quadrature-axis inductance, and ψ is the quadrature-axis inductance. f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0039] Preferably, the function discretization formula of the adjustable model is:

[0040]

[0041] Where k is a positive integer, Estimate the current along the direct axis at the current moment; Estimate the current along the quadrature axis at the current moment; Estimate the direct-axis current for the previous moment; Estimate the current for the quadrature axis at the previous moment; u d (k-1) is the direct-axis voltage at the previous moment, u d (k-1) represents the quadrature-axis voltage at the previous moment, and w(k-1) represents the rotational speed at the previous moment. Estimate the inductance along the direct axis from the previous time step. The quadrature-axis inductance is estimated for the previous moment, where ρ is the salient pole ratio of the motor.

[0042] Preferably, the initial values ​​of the direct-axis estimated inductance and the quadrature-axis estimated inductance are any positive integers.

[0043] Preferably, the function of the adaptive rate model is:

[0044]

[0045]

[0046] Where kp and ki are the regulator ratio and integral factor in the adaptive rate model, respectively, Ts is the sampling time, and z is the complex variable in the discretized z-transform. Estimate the direct-axis current at the current moment. Let ed(k) be the quadrature-axis current estimate at the current moment, eq(k) be the direct-axis current error at the current moment, ud(k) be the direct-axis voltage at the current moment, uq(k) be the quadrature-axis voltage at the current moment, w(k) be the rotational speed at the current moment, and R be the stator resistance. Estimate the inductance along the direct axis at the current moment. Estimate the inductance for the quadrature axis at the current moment, ψ f ρ is the flux linkage generated in the stator winding by the fundamental magnetic field, and ρ is the salient pole ratio of the motor.

[0047] Preferably, the vector control module includes: a first regulator for generating a quadrature-axis current reference value based on a speed reference value and the speed feedback from the motor; a second regulator for generating a quadrature-axis voltage reference value based on the quadrature-axis current reference value and the quadrature-axis current; a third regulator for generating a direct-axis voltage reference value based on the direct-axis current reference value and the direct-axis current; a first coordinate transformation unit for performing coordinate transformation on the direct-axis voltage reference value and the quadrature-axis voltage reference value to obtain two-phase control voltages in two-phase stationary coordinates; a space vector pulse width modulation unit for generating a pulse width modulation signal based on the two-phase control voltages; wherein the pulse width modulation signal is used to control the motor inverter to control the three-phase voltages of the motor; a second coordinate transformation unit for acquiring the three-phase voltages and three-phase currents of the motor and performing coordinate transformation to obtain the direct-axis voltage, quadrature-axis voltage, direct-axis current, and quadrature-axis current; an observer for acquiring the rotor position of the motor; and a differentiating unit for acquiring the motor speed based on the rotor position of the motor.

[0048] The motor parameter identification method and apparatus provided by this invention introduces the motor salient pole ratio into the adjustable model and adaptive rate model in the inductance parameter identification process, decoupling the direct-axis inductance parameter and the quadrature-axis inductance parameter. This ensures that the calculation of the quadrature-axis inductance estimate does not involve the direct-axis inductance estimate, thus avoiding direct coupling between the direct-axis and quadrature-axis inductance estimates during the calculation process. This simplifies the design of the adaptive rate model and allows for very simple calculation of the direct-axis inductance parameter L. d and quadrature axis inductance parameter L q Online identification.

[0049] Furthermore, in the inductance parameter identification module, a first preset condition is designed to correct the estimated values ​​of the direct-axis inductance current and the quadrature-axis inductance current, and a second preset condition is designed to iteratively calculate the estimated values ​​of the current and the quadrature-axis inductance current until the convergence condition is met. This avoids the non-convergence problem of the quadrature-axis and direct-axis inductance parameters during the iterative process after decoupling, and improves the accuracy of quadrature-axis and direct-axis inductance parameter identification. Attached Figure Description

[0050] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0051] Figure 1 A spatial relationship diagram of the rotor magnetic poles of a permanent magnet synchronous motor is shown.

[0052] Figure 2This diagram illustrates the principle structure of a Model Adaptive Control System (MRAS) in the prior art.

[0053] Figure 3 This diagram shows a flowchart of the motor parameter identification method provided in an embodiment of the present invention;

[0054] Figure 4 This is a flowchart of step S130 in the motor parameter identification method provided in an embodiment of the present invention;

[0055] Figure 5 This diagram shows a circuit diagram of the motor parameter identification device provided in an embodiment of the present invention.

[0056] Figure 6 The schematic diagram of the Model Adaptive Control System (MRAS) provided in the embodiment of the present invention is shown. Detailed Implementation

[0057] Various embodiments of the invention will now be described in more detail with reference to the accompanying drawings. In the various drawings, the same elements are indicated by the same or similar reference numerals. For clarity, the various parts in the drawings are not drawn to scale.

[0058] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0059] Figure 1 The diagram shows the spatial relationship of the rotor magnetic poles of a permanent magnet synchronous motor. NS represents the permanent magnet of the permanent magnet synchronous motor. The rotation of the permanent magnet rotor generates an alternating magnetic field in space. This magnetic field links with the three-phase windings, inducing a back electromotive force. At this time, the rotor magnetic field will be pulled by the stator magnetic field and rotate synchronously with the stator magnetic field.

[0060] The ABC coordinate system represents the three-phase stator coordinate system. The three-phase winding axes A, B, and C of a three-phase AC motor differ from each other by an electrical angle of 2π / 3 rad in space. The projection of the space vector onto these three coordinate axes represents the component of the space vector on these three windings. The horizontal axis d-axis of the dq coordinate system is at the same position as the N pole of the permanent magnet rotor. The vertical axis q-axis of the dq coordinate system leads the horizontal axis d-axis counterclockwise by 90 electrical degrees. In space, this coordinate system rotates synchronously with the permanent magnet rotor. The dq coordinate system is also called the rotating coordinate system.

[0061] When the permanent magnet rotor rotates synchronously with the stator rotating magnetic field, the angle between the horizontal axis d-axis (i.e., the rotor N pole) of the rotating coordinate system and the A-axis of the three-phase stator coordinate system ABC is defined as the rotor position angle θ.

[0062] In a rotating coordinate system, the voltage equation for a permanent magnet synchronous motor is:

[0063]

[0064] In the formula, R is the stator resistance of the permanent magnet synchronous motor, i d Let i be the direct-axis current, iq be the quadrature-axis current, and L be the quadrature-axis current. d For the direct-axis inductance parameters, L q Let ψ be the quadrature axis inductance parameter. f ω represents the flux linkage generated in the stator winding by the fundamental magnetic field; ω represents the motor speed.

[0065] As can be seen from the above equations, the motor resistance R and flux linkage are not affected by the quadrature-axis and direct-axis coupling effects, so the identification of the motor resistance R and flux linkage is simpler than that of the inductance. However, the quadrature-axis inductance parameters and the direct-axis inductance parameters are highly coupled in the motor model, especially under heavy load conditions. The cross-coupling back EMF of the quadrature and direct axes is large, and the solutions for Ld and Lq cannot be directly decoupled, which greatly increases the difficulty of inductance parameter identification.

[0066] Figure 2 The diagram illustrates the principle and structure of a Model Adaptive Control System (MRAS) in the prior art. Figure 2 As shown, the Model Reference Adaptive (MRAS) algorithm requires two models: an adjustable model containing the parameters to be estimated (e.g., quadrature-axis and direct-axis inductance parameters) and an actual reference model. The same input is applied to both models, and their outputs are compared to obtain the output error between the adjustable and reference models. An appropriate adaptive rate is designed based on this error to achieve parameter identification. An accurate adjustable model and appropriate parameters ensure that the system parameters converge quickly to their actual values. The main idea of ​​MRAS is to construct two models with output quantities of the same physical meaning. The motor equations without position parameters are used as the reference model, while the equations containing the parameters to be estimated are used as the adjustable model. An appropriate adaptive rate is constructed using the difference between the output quantities of the two models to adjust the parameters of the adjustable model in real time, so that the output of the adjustable model tracks the output of the reference model. Its structural framework... Figure 2 As shown, Figure 2 In this context, u represents the input signal, which consists of the direct-axis voltage ud, the quadrature-axis voltage uq, and the motor speed w. x represents the output signal of the reference model, which outputs the direct-axis current id and the quadrature-axis current iq. The output signal of the adjustable model is the direct-axis estimated current. and cross-axis estimation of current e represents the difference between the output values.

[0067] Figure 3 A flowchart illustrating the motor parameter identification method provided in an embodiment of the present invention is shown. Figure 3 As shown, the motor parameter identification method includes the following steps.

[0068] In step S100, a reference model of the motor is constructed based on the MRAS method. The motor is then controlled to operate in speed closed-loop and current closed-loop control modes according to the reference model, and the direct-axis voltage u at the current moment is obtained. d (k), quadrature axis voltage u q (k), Direct-axis current i d (k), quadrature axis current i q( k) and motor speed w(k).

[0069] Specifically, the motor is controlled to operate in speed closed-loop and current closed-loop control modes, and the three-phase voltage u of the motor at the current moment (time k) is... a u b and u c The direct-axis voltage u of the motor at the current time (time k) is obtained by sampling and coordinate transformation. d (k) and quadrature axis voltage u q (k). The three-phase current i of the motor at the current time (time k). a i b and i c The direct-axis current i of the motor at the current time (time k) is obtained by sampling and coordinate transformation. d (k) and quadrature axis current i q (k). The rotational speed ω(k) of the motor at the current time (time k) is obtained by observing the rotor position θ(k) of the motor at the current time (time k).

[0070] When the motor starts, the motor's vector control module uses the speed reference value w* and the direct-axis current reference value i. d *Generates a direct-axis voltage reference value u d and quadrature axis voltage reference value u q * Drives the motor to run; after the motor starts running, it enters the speed closed-loop and current closed-loop control modes, based on the speed reference value w*, speed w, and direct-axis current reference value i. d * Direct-axis current i d Cross-axis current i q Generate direct-axis voltage reference value u d * and quadrature axis voltage reference value u q *To control the operation of the motor, thereby achieving closed-loop speed control and closed-loop current control.

[0071] In this embodiment, the direct-axis current reference value i d * represents the preset value, which is usually 0.5A.

[0072] The function of the reference model is as follows:

[0073]

[0074] Among them, id For direct-axis current, i q For quadrature-axis current, u d For direct-axis voltage, u q Where is the quadrature-axis voltage, w is the rotational speed, and L is the rotational speed. d For a direct-axis inductor, L q For quadrature axis inductance, ψ f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0075] In both speed closed-loop and current closed-loop control modes, a speed reference value w* and a direct-axis current reference value i are provided to the motor control circuit. d *To obtain the direct-axis voltage reference value u at the current time (time k). d *(k), Quadrature axis voltage reference value u q *(k) represents the direct-axis voltage reference value u at the current time (time k). d *(k), Quadrature axis voltage reference value u q (k) Provided to the motor to drive the motor to operate.

[0076] A basic vector control module is constructed based on a reference model. This module includes a speed closed-loop control unit, a current closed-loop control unit, a coordinate transformation unit, and a space vector pulse width modulation unit. The speed closed-loop control unit includes a first regulator that generates a quadrature-axis current reference value i based on the speed reference value w* and the speed w. q * The current closed-loop control unit includes a second regulator and a third regulator, wherein the second regulator operates based on the quadrature-axis current reference value i. q * and quadrature axis current i q Generate quadrature axis voltage reference value u q *, The third regulator is based on the direct-axis current reference value i d * and direct-axis current i d Generate direct-axis voltage reference value u d *. The first coordinate transformation unit will transform the direct-axis voltage reference value u. d * and quadrature axis voltage reference value u q *Perform coordinate transformation (inverse Park transform) to obtain the two-phase control voltage u in two-phase stationary coordinates. α and u β The space vector pulse width modulation unit generates a pulse width modulation signal (PWM) based on the two-phase control voltage. The motor inverter then supplies three-phase voltage u to the motor according to the PWM signal. a u b and u c To control the motor's operation. The second coordinate transformation unit samples the motor's three-phase voltages and performs coordinate transformations (Clark transformation and Park transformation) to obtain the direct-axis voltage u. d and quadrature axis voltage u q; and sampling the three-phase current of the motor and performing coordinate transformation to obtain the direct-axis current i. d and cross-axis current i q The observer is used to obtain the rotor position θ of the motor; the differentiating unit is used to obtain the motor speed w based on the rotor position θ.

[0077] In step S110, an adjustable model of the motor is constructed based on the MRAS method, according to the current quadrature-axis voltage u of the motor. q Direct-axis voltage u d Motor speed w and estimated direct-axis inductance from the previous moment. and cross-axis estimation of inductance Obtain the direct-axis estimated current at the current moment. and cross-axis estimation of current

[0078] In this embodiment, the function of the adjustable model is:

[0079]

[0080] in, Estimating current for the direct axis Estimate the current for the quadrature axis; Estimate inductance for the direct axis. To estimate the inductance for the quadrature axis, ω is the motor speed, and ψ is... f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0081] Based on the function of the aforementioned adjustable model, the direct-axis estimated current can be obtained. and cross-axis estimation of current Iteration formula:

[0082]

[0083] Where k is a positive integer.

[0084] The discretization formula for the adjustable model using the convexity ratio is as follows:

[0085]

[0086] Where k is a positive integer.

[0087] In this embodiment, Estimate the current along the direct axis at the current moment; Estimate the current along the quadrature axis at the current moment; Estimate the direct-axis current for the previous moment; Estimate the current for the quadrature axis at the previous moment; ud (k-1) is the direct-axis voltage at the previous moment, u d (k-1) represents the quadrature-axis voltage at the previous moment, and w(k-1) represents the rotational speed at the previous moment. Estimate the inductance along the direct axis from the previous time step. Estimate the inductance for the quadrature axis from the previous time step. In the first iteration, The initial value is 0. The initial value is any non-zero positive number, for example The initial value is 1.

[0088] In a preferred embodiment, since the permanent magnet synchronous motor operates in a speed closed-loop and current closed-loop state, the quadrature-axis voltage reference value u q *and the quadrature-axis voltage u q The values ​​are equal, and the direct-axis voltage reference value u d *and direct-axis voltage u d To save on hardware costs for sampling three-phase voltages, the current quadrature-axis voltage reference value u can be used. q *Reference value of direct-axis voltage u d * Replace the current quadrature-axis voltage u q With direct-axis voltage u d Perform iterative calculations.

[0089] In step S120, based on the direct-axis current i d Cross-axis current i q Direct-axis current estimation and cross-axis estimation of current Obtain the direct-axis error current e d and cross-axis error current e q .

[0090] In this embodiment, the direct-axis error current Cross-axis error current

[0091] In step S130, the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model are adjusted through the feedback of the adaptive rate model, so that the direct-axis estimated current of the adjustable model is... The direct-axis error current e between the direct-axis current id and the reference model d and cross-axis estimated current The cross-axis error current e between the cross-axis current iq and the cross-axis current q The convergence occurs when the adaptive rate model and the adjustable model utilize the saliency ratio of the motor. The saliency ratio ρ is the ratio of the quadrature-axis inductance Lq to the direct-axis inductance Ld. The saliency ratio can be obtained directly from the motor specifications or measured using a bridge circuit.

[0092] In this embodiment, the function of the adaptive rate model is as follows:

[0093]

[0094]

[0095] Where kp and ki are the regulator ratio and integral factor in the adaptive rate model, respectively, Ts is the sampling time, and z is the complex variable in the discretized z-transform. Estimate the direct-axis current at the current moment. Let ed(k) be the quadrature-axis current estimate at the current moment, eq(k) be the direct-axis current error at the current moment, ud(k) be the direct-axis voltage at the current moment, uq(k) be the quadrature-axis voltage at the current moment, w(k) be the rotational speed at the current moment, and R be the stator resistance. Estimate the inductance along the direct axis at the current moment. Estimate the inductance for the quadrature axis at the current moment, ψ f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0096] Specifically, see Figure 4 Step S130 includes steps S131 to S136.

[0097] In step S131, it is determined whether the direct-axis error current and the quadrature-axis error current meet the first preset condition.

[0098] In this embodiment, the first preset condition is, for example, that the direct-axis error current is less than 30% of the direct-axis current, and the quadrature-axis error current is less than 30% of the quadrature-axis current; that is, |e d (k)<i d (k)*30%|, and |e q (k)<i q (k)*30%|.

[0099] In step S132, if the direct-axis error current and the quadrature-axis error current do not meet the first preset condition, the current direct-axis current and the quadrature-axis current at the current moment are used as the direct-axis estimated current and the quadrature-axis estimated current and input into the adjustable model to iteratively calculate the next moment's direct-axis estimated current and the quadrature-axis estimated current until the direct-axis error current and the quadrature-axis error current meet the first preset condition.

[0100] In this embodiment, if |e d (k)≥i d (k)*30%|, and |e q (k)≥i q (k)*30%|, then Estimate the direct-axis current at the current moment and cross-axis estimation of current The input is fed into the adjustable model for iterative calculation of the direct-axis estimated current at the next time step. and cross-axis estimation of current Until the direct-axis error current and the quadrature-axis error current meet the first preset condition.

[0101] In step S133, if the direct-axis error current and quadrature-axis error current satisfy the first preset condition, the estimated direct-axis inductance at the current moment is obtained based on the current direct-axis voltage, quadrature-axis voltage, estimated direct-axis current, estimated quadrature-axis current, direct-axis error current, quadrature-axis error current, motor salient pole ratio, and adaptive rate model. and cross-axis estimation of inductance

[0102] In step S134, it is determined whether the direct axis error current and the quadrature axis error current meet the second preset condition.

[0103] In this embodiment, if |e d (k)<i d (k)*30%|, and |e q (k)<i q (k)*30%|, then determine the direct-axis error current e at the current moment. d (k) and cross-axis error current e q (k) Whether the second preset condition is satisfied. The second preset condition is, for example, |e d (k)≤i d (k)*10%|, and |e q (k)≤i q (k)*10%|.

[0104] In step S135, if the direct-axis error current and quadrature-axis error current do not meet the second preset condition, the current direct-axis estimated inductance is... and cross-axis estimation of inductance The current is input into the adjustable model for iterative calculation of the direct-axis estimated current and the quadrature-axis estimated current at the next time step until the direct-axis error current and the quadrature-axis error current meet the second preset condition.

[0105] In this embodiment, if |i d (k)*10%<e d (k)<i d (k)*30%|, and |i q (k)*10%<e q (k)<i q (k)*30%|, the estimated direct-axis inductance at the current moment and cross-axis estimation of inductance The input is fed into the adjustable model for iterative calculation of the direct-axis estimated current at the next time step. and cross-axis estimation of current Until the direct-axis error current and the quadrature-axis error current meet the second preset condition.

[0106] In step S136, if the direct-axis error current and the quadrature-axis error current satisfy the second preset condition, then the current direct-axis estimated inductance is... and cross-axis estimation of inductance The output serves as the direct-axis inductance and quadrature-axis inductance of the motor.

[0107] In this embodiment, if |e d (k)≤i d (k)*10%|, and |e q (k)≤i q (k)*10%|, then the direct-axis estimated inductance at the current moment will be used. and cross-axis estimation of inductance The output is the direct-axis inductance Ld and quadrature-axis inductance Lq of the motor.

[0108] The motor parameter identification method provided by this invention introduces the motor salient pole ratio into the adjustable model and adaptive rate model in the inductance parameter identification process, decoupling the direct-axis inductance parameter and the quadrature-axis inductance parameter. This ensures that the calculation of the quadrature-axis inductance estimate does not involve the direct-axis inductance estimate, thus avoiding direct coupling between the direct-axis and quadrature-axis inductance estimates during the calculation process. This simplifies the design of the adaptive rate model and makes the calculation of the direct-axis inductance parameter L very simple. d and quadrature axis inductance parameter L q Online identification.

[0109] Furthermore, in the inductance parameter identification module, a first preset condition is designed to correct the estimated values ​​of the direct-axis inductance current and the quadrature-axis inductance current, and a second preset condition is designed to iteratively calculate the estimated values ​​of the current and the quadrature-axis inductance current until the convergence condition is met. This avoids the non-convergence problem of the quadrature-axis and direct-axis inductance parameters during the iterative process after decoupling, and improves the accuracy of quadrature-axis and direct-axis inductance parameter identification.

[0110] Figure 5 This diagram shows a circuit diagram of the motor parameter identification device provided in an embodiment of the present invention. Figure 6 The diagram illustrates the principle structure of the Model Adaptive Control System (MRAS) provided in an embodiment of the present invention. Figure 5 As shown, the motor parameter identification device 100 includes a vector control module 110 and an inductance identification module 120.

[0111] The vector control module 110 is used to construct and control the motor to operate in speed closed-loop and current closed-loop control modes based on the motor reference model, and to obtain the direct-axis voltage, quadrature-axis voltage, direct-axis current, quadrature-axis current and motor speed of the motor.

[0112] The function of the reference model is as follows:

[0113]

[0114] Among them, i d For direct-axis current, i q For quadrature-axis current, u d For direct-axis voltage, u q Where is the quadrature-axis voltage, w is the rotational speed, and L is the rotational speed. d For a direct-axis inductor, L q For quadrature axis inductance, ψ f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0115] In both speed closed-loop and current closed-loop control modes, a speed reference value w* and a direct-axis current reference value i are provided to the motor control circuit. d *To obtain the direct-axis voltage reference value u at the current time (time k). d *(k), Quadrature axis voltage reference value u q *(k) represents the direct-axis voltage reference value u at the current time (time k). d *(k), Quadrature axis voltage reference value u q (k) Provided to the motor to drive the motor. Direct-axis current reference value i d * represents the preset value, which is usually 0.5A.

[0116] In this embodiment, the vector control module 110 includes a first regulator 111, a second regulator 112, a third regulator 113, a first coordinate transformation unit 114, a space vector pulse width modulation unit 115, a second coordinate transformation unit 116, an observer 117, and a differentiating unit 118.

[0117] The first regulator 111 is used to generate a cross-axis current reference value i based on the speed reference value w* and the speed w. q *; The second regulator 112 is used to adjust according to the cross-axis current reference value i q * and quadrature axis current i q Generate quadrature axis voltage reference value u q *; The third regulator 113 is used to adjust the direct-axis current reference value i d * and direct-axis current i d Generate direct-axis voltage reference value u d *; The first coordinate transformation unit 114 is used to transform the direct-axis voltage reference value u d* and quadrature axis voltage reference value u q *Perform coordinate transformation (inverse Park transform) to obtain the two-phase control voltage u in two-phase stationary coordinates. α and u β The space vector pulse width modulation unit 115 is used to generate a pulse width modulation signal (PWM) based on the two-phase control voltage; wherein, the PWM signal is used to control the motor inverter, thereby controlling the three-phase voltage u of the motor. a u b and u c The second coordinate transformation unit 116 is used to acquire the three-phase voltage and three-phase current of the motor and perform coordinate transformation to obtain the direct-axis voltage u. d Cross-axis voltage u q Direct-axis current i d and cross-axis current i q The observer 117 is used to obtain the rotor position θ of the motor; the differential unit 118 is used to obtain the motor speed w based on the rotor position θ of the motor.

[0118] The inductance identification module 120 is used to construct, based on the adjustable model and adaptive rate model of the motor, the estimated direct-axis current and quadrature-axis current of the motor based on the direct-axis voltage and quadrature-axis voltage; the estimated direct-axis error current based on the direct-axis current of the reference model and the estimated direct-axis current of the adjustable model; and the estimated quadrature-axis error current based on the quadrature-axis current of the reference model and the estimated quadrature-axis current of the adjustable model; and to adjust the estimated direct-axis inductance and quadrature-axis inductance in the adjustable model through the feedback of the adaptive rate model, so that the estimated direct-axis error current and quadrature-axis error current converge, thereby obtaining the direct-axis inductance parameters and quadrature-axis inductance parameters that satisfy the first preset condition and the second preset condition; wherein, the adaptive rate model and the adjustable model adopt the salient pole ratio of the motor. The salient pole ratio is the ratio of the quadrature-axis inductance to the direct-axis inductance.

[0119] In this embodiment, the inductor identification module includes an adjustable model unit 121, an adaptive rate model unit 122, a first judgment unit 123, and a second judgment unit 124.

[0120] The adjustable model unit 121 is used to obtain the estimated direct-axis current and estimated quadrature-axis current of the motor based on the direct-axis voltage and quadrature-axis voltage of the motor.

[0121] In this embodiment, the adjustable model unit 121 adjusts the current quadrature-axis voltage u of the motor. q Direct-axis voltage u d Motor speed w and estimated direct-axis inductance from the previous moment. and cross-axis estimation of inductance Obtain the direct-axis estimated current at the current moment. and cross-axis estimation of current

[0122] The function of the adjustable model is:

[0123]

[0124] in, Estimating current for the direct axis Estimate the current for the quadrature axis; Estimate inductance for the direct axis. To estimate the inductance for the quadrature axis, ω is the motor speed, and ψ is... f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0125] Based on the function of the aforementioned adjustable model, the direct-axis estimated current can be obtained. and cross-axis estimation of current Iteration formula:

[0126]

[0127] Where k is a positive integer.

[0128] The discretization formula for the adjustable model using the convexity ratio is as follows:

[0129]

[0130] Where k is a positive integer.

[0131] In this embodiment, Estimate the current along the direct axis at the current moment; Estimate the current along the quadrature axis at the current moment; Estimate the direct-axis current for the previous moment; Estimate the current for the quadrature axis at the previous moment; u d (k-1) is the direct-axis voltage at the previous moment, u d (k-1) represents the quadrature-axis voltage at the previous moment, and w(k-1) represents the rotational speed at the previous moment. Estimate the inductance along the direct axis from the previous time step. Estimate the inductance for the quadrature axis from the previous time step. In the first iteration, The initial value is 0. The initial value is any non-zero positive number, for example The initial value is 1.

[0132] In a preferred embodiment, since the permanent magnet synchronous motor operates in a speed closed-loop and current closed-loop state, the quadrature-axis voltage reference value u q *and the quadrature-axis voltage u q The values ​​are equal, and the direct-axis voltage reference value ud *and direct-axis voltage u d To save on hardware costs for sampling three-phase voltages, the current quadrature-axis voltage reference value u can be used. q *Reference value of direct-axis voltage u d * Replace the current quadrature-axis voltage u q With direct-axis voltage u d Perform iterative calculations.

[0133] The adaptive rate model unit 122 is used to obtain the quadrature axis error current based on the quadrature axis current and the quadrature axis estimated current; and to adjust the direct axis estimated inductance and quadrature axis estimated inductance in the adjustable model through the feedback of the adaptive rate model, so that the direct axis error current and the quadrature axis error current converge, so as to obtain the direct axis inductance parameters and quadrature axis inductance parameters that satisfy the first preset condition and the second preset condition, wherein the adaptive rate model and the adjustable model adopt the salient pole ratio of the motor.

[0134] In this embodiment, the direct-axis error current Cross-axis error current

[0135] In this embodiment, the function of the adaptive rate model is as follows:

[0136]

[0137]

[0138] Where kp and ki are the regulator ratio and integral factor in the adaptive rate model, respectively, Ts is the sampling time, and z is the complex variable in the discretized z-transform. Estimate the direct-axis current at the current moment. Let ed(k) be the quadrature-axis current estimate at the current moment, eq(k) be the direct-axis current error at the current moment, ud(k) be the direct-axis voltage at the current moment, uq(k) be the quadrature-axis voltage at the current moment, w(k) be the rotational speed at the current moment, and R be the stator resistance. Estimate the inductance along the direct axis at the current moment. Estimate the inductance for the quadrature axis at the current moment, ψ f It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

[0139] The first judgment unit 123 is used to determine whether the direct axis error current and the quadrature axis error current meet the first preset condition.

[0140] In this embodiment, the first preset condition is, for example, that the direct-axis error current is less than 30% of the direct-axis current, and the quadrature-axis error current is less than 30% of the quadrature-axis current; that is, |e d(k)<i d (k)*30%|, and |e q (k)<i q (k)*30%|.

[0141] The adjustable model unit 121 is further configured to, if the direct-axis error current and the quadrature-axis error current do not meet the first preset condition, input the current direct-axis current and the quadrature-axis current at the current moment as the direct-axis estimated current and the quadrature-axis estimated current into the adjustable model for iterative calculation of the next moment's direct-axis estimated current and the quadrature-axis estimated current until the direct-axis error current and the quadrature-axis error current meet the first preset condition.

[0142] In this embodiment, if |e d (k)≥i d (k)*30%|, and |e q (k)≥i q (k)*30%|, then Estimate the direct-axis current at the current moment and cross-axis estimation of current The input is fed into the adjustable model for iterative calculation of the direct-axis estimated current at the next time step. and cross-axis estimation of current Until the direct-axis error current and the quadrature-axis error current meet the first preset condition.

[0143] The adaptive rate model unit 122 is further configured to, if the direct-axis error current and quadrature-axis error current satisfy the first preset condition, obtain the current-time direct-axis estimated inductance and quadrature-axis estimated inductance based on the current-time direct-axis voltage, quadrature-axis voltage, direct-axis estimated current, quadrature-axis estimated current, direct-axis error current, quadrature-axis error current, motor salient pole ratio, and adaptive rate model.

[0144] The second judgment unit 124 is used to determine whether the direct axis error current and the quadrature axis error current meet the second preset condition.

[0145] In this embodiment, if |e d (k)<i d (k)*30%|, and |e q (k)<i q (k)*30%|, then determine the direct-axis error current e at the current moment. d (k) and cross-axis error current e q (k) Whether the second preset condition is satisfied. The second preset condition is, for example, |e d (k)≤i d (k)*10%|, and |e q (k)≤i q (k)*10%|.

[0146] The adaptive rate model unit 122 is further configured to, if the direct-axis error current and the quadrature-axis error current do not meet the second preset condition, input the current estimated inductance and the quadrature-axis estimated inductance into the adjustable model for iterative calculation of the next estimated current and the quadrature-axis estimated current until the direct-axis error current and the quadrature-axis error current meet the second preset condition.

[0147] In this embodiment, if |i d (k)*10%<e d (k)<i d (k)*30%|, and |i q (k)*10%<e q (k)<i q (k)*30%|, the estimated direct-axis inductance at the current moment and cross-axis estimation of inductance The input is fed into the adjustable model for iterative calculation of the direct-axis estimated current at the next time step. and cross-axis estimation of current Until the direct-axis error current and the quadrature-axis error current meet the second preset condition.

[0148] The adaptive rate model unit 122 is further configured to output the current estimated inductance and quadrature estimated inductance as the motor's current estimated inductance and quadrature inductance if the direct-axis error current and quadrature-axis error current satisfy the second preset condition.

[0149] In this embodiment, if |e d (k)≤i d (k)*10%|, and |e q (k)≤i q (k)*10%|, then the direct-axis estimated inductance at the current moment will be used. and cross-axis estimation of inductance The output is the direct-axis inductance Ld and quadrature-axis inductance Lq of the motor.

[0150] The motor parameter identification method and apparatus provided by this invention introduces the motor salient pole ratio into the adjustable model and adaptive rate model in the inductance parameter identification process, decoupling the direct-axis inductance parameter and the quadrature-axis inductance parameter. This ensures that the calculation of the quadrature-axis inductance estimate does not involve the direct-axis inductance estimate, thus avoiding direct coupling between the direct-axis and quadrature-axis inductance estimates during the calculation process. This simplifies the design of the adaptive rate model and allows for very simple calculation of the direct-axis inductance parameter L. d and quadrature axis inductance parameter L q Online identification.

[0151] Furthermore, in the inductance parameter identification module, a first preset condition is designed to correct the estimated values ​​of the direct-axis inductance current and the quadrature-axis inductance current, and a second preset condition is designed to iteratively calculate the estimated values ​​of the current and the quadrature-axis inductance current until the convergence condition is met. This avoids the non-convergence problem of the quadrature-axis and direct-axis inductance parameters during the iterative process after decoupling, and improves the accuracy of quadrature-axis and direct-axis inductance parameter identification.

[0152] As described above, these embodiments of the present invention do not exhaustively cover all details, nor do they limit the invention to the specific embodiments described. Clearly, many modifications and variations can be made based on the above description. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to effectively utilize the invention and its modifications. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for identifying motor parameters, characterized in that, include: The motor is controlled to operate in speed closed-loop and current closed-loop modes based on the motor reference model, and the direct-axis voltage, quadrature-axis voltage, direct-axis current, quadrature-axis current and motor speed are obtained. Based on the adjustable model of the motor, the direct-axis voltage of the motor, and the quadrature-axis voltage of the motor, the estimated direct-axis current and the estimated quadrature-axis current of the motor are obtained; The direct-axis error current is obtained based on the direct-axis current and the estimated direct-axis current, and the quadrature-axis error current is obtained based on the quadrature-axis current and the estimated quadrature-axis current; The direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model are adjusted by the feedback of the adaptive rate model, so that the direct-axis error current and the quadrature-axis error current converge, so as to obtain the direct-axis inductance parameters and quadrature-axis inductance parameters that satisfy the first preset condition and the second preset condition. The adaptive rate model and the adjustable model use the salient pole ratio of the motor. The first preset condition is that the direct axis error current is less than 30% of the direct axis current, and the quadrature axis error current is less than 30% of the quadrature axis current; the second preset condition is that the direct axis error current is not greater than 10% of the direct axis current, and the quadrature axis error current is not greater than 10% of the quadrature axis current.

2. The motor parameter identification method according to claim 1, characterized in that, The salient pole ratio is the ratio of quadrature axis inductance to direct axis inductance.

3. The motor parameter identification method according to claim 1, characterized in that, The direct-axis and quadrature-axis estimated inductances in the adjustable model are adjusted through the feedback mechanism of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, including: Determine whether the direct-axis error current and the quadrature-axis error current meet the first preset condition; If the direct-axis error current and the quadrature-axis error current do not meet the first preset condition, then the current direct-axis current and the quadrature-axis current at the current moment are used as the direct-axis estimated current and the quadrature-axis estimated current and input into the adjustable model to iteratively calculate the next moment's direct-axis estimated current and the quadrature-axis estimated current until the direct-axis error current and the quadrature-axis error current meet the first preset condition.

4. The motor parameter identification method according to claim 3, characterized in that, Adjusting the direct-axis and quadrature-axis estimated inductances in the adjustable model through the feedback of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, also includes: If the direct-axis error current and quadrature-axis error current satisfy the first preset condition, the direct-axis estimated inductance and quadrature-axis estimated inductance at the current moment are obtained based on the current direct-axis voltage, quadrature-axis voltage, estimated direct-axis current, estimated quadrature-axis current, direct-axis error current, quadrature-axis error current, motor salient pole ratio, and adaptive rate model.

5. The motor parameter identification method according to claim 4, characterized in that, Adjusting the direct-axis and quadrature-axis estimated inductances in the adjustable model through the feedback mechanism of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, also includes: Determine whether the direct-axis error current and the quadrature-axis error current satisfy the second preset condition; If the direct-axis error current and quadrature-axis error current do not meet the second preset condition, the current estimated direct-axis inductance and quadrature-axis inductance are input into the adjustable model for iterative calculation of the next estimated direct-axis current and quadrature-axis current until the direct-axis error current and quadrature-axis error current meet the second preset condition.

6. The motor parameter identification method according to claim 5, characterized in that, Adjusting the direct-axis and quadrature-axis estimated inductances in the adjustable model through the feedback mechanism of the adaptive rate model, so that the direct-axis error current and quadrature-axis error current converge, also includes: If the direct-axis error current and quadrature-axis error current meet the second preset condition, then the current-time estimated direct-axis inductance and quadrature-axis inductance outputs are used as the direct-axis inductance and quadrature-axis inductance of the motor.

7. The motor parameter identification method according to claim 6, characterized in that, The first preset condition is ,as well as The second preset condition is ,as well as ,in, This represents the direct-axis error current at the current moment. This represents the direct-axis current at the current moment; The quadrature-axis error current at the current moment. The quadrature-axis current is at the current moment.

8. The motor parameter identification method according to claim 1, characterized in that, The function of the reference model is: ； Where id is the direct-axis current, iq is the quadrature-axis current, ud is the direct-axis voltage, uq is the quadrature-axis voltage, w is the rotational speed, R is the stator resistance, Ld is the direct-axis inductance, and Lq is the quadrature-axis inductance. It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

9. The motor parameter identification method according to claim 1, characterized in that, The function discretization formula for the adjustable model is as follows: ； Where k is a positive integer, Estimate the current along the direct axis at the current moment; Estimate the current along the quadrature axis at the current moment; Estimate the direct-axis current for the previous moment; Estimate the current for the quadrature axis at the previous moment; The direct-axis voltage at the previous moment. Let w(k-1) be the quadrature-axis voltage at the previous moment, and w(k-1) be the rotational speed at the previous moment. Estimate the inductance along the direct axis from the previous time step. Estimate the inductance for the quadrature axis at the previous time step. This represents the salient pole ratio of the motor.

10. The motor parameter identification method according to claim 9, characterized in that, The initial values ​​for the direct-axis estimated current and the quadrature-axis estimated current are 0, and the initial values ​​for the direct-axis estimated inductance and the quadrature-axis estimated inductance are any positive integers.

11. The motor parameter identification method according to claim 1, characterized in that, The function of the adaptive rate model is: ； ； Where kp and ki are the regulator ratio and integral factor in the adaptive rate model, respectively, Ts is the sampling time, and z is the complex variable in the discretized z-transform. Estimate the direct-axis current at the current moment. Let ed(k) be the quadrature-axis current estimate at the current moment, eq(k) be the direct-axis current error at the current moment, ud(k) be the direct-axis voltage at the current moment, uq(k) be the quadrature-axis voltage at the current moment, w(k) be the rotational speed at the current moment, and R be the stator resistance. Estimate the inductance along the direct axis at the current moment. Estimate the inductance for the quadrature axis at the current moment. The magnetic flux linkage generated in the stator winding by the fundamental magnetic field. This represents the salient pole ratio of the motor.

12. A motor parameter identification device, characterized in that, include: The vector control module is used to construct and control the motor to operate in speed closed-loop and current closed-loop control modes based on the motor reference model, and to obtain the motor's direct-axis voltage, quadrature-axis voltage, direct-axis current, quadrature-axis current and motor speed. The inductor identification module is used to construct, based on the motor's adjustable model and adaptive rate model, the estimated direct-axis current and estimated quadrature-axis current of the motor based on the motor's direct-axis voltage and quadrature-axis voltage; The direct-axis error current is obtained from the direct-axis current of the reference model and the direct-axis estimated current of the adjustable model, and the quadrature-axis error current is obtained from the quadrature-axis current of the reference model and the quadrature-axis estimated current of the adjustable model. And by using the feedback effect of the adaptive rate model, the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model are adjusted so that the direct-axis error current and quadrature-axis error current converge, so as to obtain the direct-axis inductance parameters and quadrature-axis inductance parameters that satisfy the first preset condition and the second preset condition. The adaptive rate model and the adjustable model use the salient pole ratio of the motor. The first preset condition is that the direct axis error current is less than 30% of the direct axis current, and the quadrature axis error current is less than 30% of the quadrature axis current; the second preset condition is that the direct axis error current is not greater than 10% of the direct axis current, and the quadrature axis error current is not greater than 10% of the quadrature axis current.

13. The motor parameter identification device according to claim 12, characterized in that, The salient pole ratio is the ratio of quadrature axis inductance to direct axis inductance.

14. The motor parameter identification device according to claim 12, characterized in that, The inductor identification module includes: An adjustable model unit is used to obtain the estimated direct-axis current and estimated quadrature-axis current of the motor based on the direct-axis voltage and quadrature-axis voltage of the motor. An adaptive rate model unit is used to obtain the quadrature-axis error current based on the quadrature-axis current of the reference model and the quadrature-axis estimated current of the adjustable model; and to adjust the direct-axis estimated inductance and quadrature-axis estimated inductance in the adjustable model through the feedback of the adaptive rate model, so that the direct-axis error current and the quadrature-axis error current converge, so as to obtain the direct-axis inductance parameters and quadrature-axis inductance parameters that satisfy the first preset condition and the second preset condition, wherein the adaptive rate model and the adjustable model adopt the salient pole ratio of the motor.

15. The motor parameter identification device according to claim 14, characterized in that, The inductor identification module also includes: The first judgment unit is used to determine whether the direct axis error current and the quadrature axis error current meet the first preset condition; The adjustable model unit is also used to input the current direct-axis current and quadrature-axis current as the direct-axis estimated current and quadrature-axis estimated current into the adjustable model for iterative calculation of the next time direct-axis estimated current and quadrature-axis estimated current until the direct-axis error current and quadrature-axis error current meet the first preset condition if the direct-axis error current and quadrature-axis error current do not meet the first preset condition.

16. The motor parameter identification device according to claim 15, characterized in that, The adaptive rate model unit is further configured to, if the direct-axis error current and quadrature-axis error current satisfy the first preset condition, obtain the current-time direct-axis estimated inductance and quadrature-axis estimated inductance based on the current-time direct-axis voltage, quadrature-axis voltage, direct-axis estimated current, quadrature-axis estimated current, direct-axis error current, quadrature-axis error current, motor salient pole ratio, and adaptive rate model.

17. The motor parameter identification device according to claim 16, characterized in that, The inductor identification module also includes: The second judgment unit is used to determine whether the direct axis error current and the quadrature axis error current meet the second preset condition. The adaptive rate model unit is further configured to, if the direct-axis error current and quadrature-axis error current do not meet the second preset condition, input the current estimated inductance and quadrature-axis estimated inductance into the adjustable model for iterative calculation of the next estimated current and quadrature-axis estimated current until the direct-axis error current and quadrature-axis error current meet the second preset condition.

18. The motor parameter identification device according to claim 17, characterized in that, The adaptive rate model unit is further configured to output the current estimated inductance and quadrature axis estimated inductance as the motor's current estimated inductance and quadrature axis inductance if the direct-axis error current and quadrature axis error current satisfy the second preset condition.

19. The motor parameter identification device according to claim 18, characterized in that, The first preset condition is ,as well as The second preset condition is ,as well as ,in, This represents the direct-axis error current at the current moment. This represents the direct-axis current at the current moment; The quadrature-axis error current at the current moment. The quadrature-axis current is at the current moment.

20. The motor parameter identification device according to claim 12, characterized in that, The function of the reference model is: ； Where id is the direct-axis current, iq is the quadrature-axis current, ud is the direct-axis voltage, uq is the quadrature-axis voltage, w is the rotational speed, R is the stator resistance, Ld is the direct-axis inductance, and Lq is the quadrature-axis inductance. It is the magnetic flux generated in the stator winding by the fundamental magnetic field.

21. The motor parameter identification method according to claim 12, characterized in that, The formula is: ； Where k is a positive integer, Estimate the current along the direct axis at the current moment; Estimate the current along the quadrature axis at the current moment; Estimate the direct-axis current for the previous moment; Estimate the current for the quadrature axis at the previous moment; The direct-axis voltage at the previous moment. Let w(k-1) be the quadrature-axis voltage at the previous moment, and w(k-1) be the rotational speed at the previous moment. Estimate the inductance along the direct axis from the previous time step. Estimate the inductance for the quadrature axis at the previous time step. This represents the salient pole ratio of the motor.

22. The motor parameter identification device according to claim 21, characterized in that, The initial values ​​for the direct-axis estimated inductance and the quadrature-axis estimated inductance are any positive integers.

23. The motor parameter identification device according to claim 12, characterized in that, The function of the adaptive rate model is: ； ； Where kp and ki are the regulator ratio and integral factor in the adaptive rate model, respectively, Ts is the sampling time, and z is the complex variable in the discretized z-transform. Estimate the direct-axis current at the current moment. Let ed(k) be the quadrature-axis current estimate at the current moment, eq(k) be the direct-axis current error at the current moment, ud(k) be the direct-axis voltage at the current moment, uq(k) be the quadrature-axis voltage at the current moment, w(k) be the rotational speed at the current moment, and R be the stator resistance. Estimate the inductance along the direct axis at the current moment. Estimate the inductance for the quadrature axis at the current moment. The magnetic flux linkage generated in the stator winding by the fundamental magnetic field. This represents the salient pole ratio of the motor.

24. The motor parameter identification device according to claim 12, characterized in that, The vector control module includes: The first regulator is used to generate a quadrature-axis current reference value based on the speed reference value and the speed fed back by the motor; The second regulator is used to generate a quadrature-axis voltage reference value based on the quadrature-axis current reference value and the quadrature-axis current; The third regulator is used to generate a direct-axis voltage reference value based on the direct-axis current reference value and the direct-axis current; The first coordinate transformation unit is used to perform coordinate transformation on the direct-axis voltage reference value and the quadrature-axis voltage reference value to obtain the two-phase control voltage in the two-phase stationary coordinates. The space vector pulse width modulation unit is used to generate pulse width modulation signals based on the two-phase control voltage. The pulse width modulation signal is used to control the inverter of the motor, thereby controlling the three-phase voltage of the motor. The second coordinate transformation unit is used to obtain the three-phase voltage and three-phase current of the motor and perform coordinate transformation to obtain the direct-axis voltage, quadrature-axis voltage, direct-axis current and quadrature-axis current; An observer is used to obtain the rotor position of the motor; The differential unit is used to obtain the motor speed based on the rotor position of the motor.

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