CN-121664038-B - Weak magnetic control method based on permanent magnet synchronous motor self-adaptive parameter identification

CN121664038BCN 121664038 BCN121664038 BCN 121664038BCN-121664038-B

Abstract

The invention provides a field-weakening control method based on permanent magnet synchronous motor self-adaptive parameter identification, and relates to the technical field of motor control, wherein the method solves the problem of control performance reduction caused by parameter time variation by fusing chaotic inertia weight and Gaussian disturbance improved particle swarm optimization (CIPSO) to identify stator resistance, AC-DC axis inductance and permanent magnet flux linkage on line; and triggering lead angle field weakening control through voltage saturation criteria above the rated rotating speed, dynamically introducing lead angle correction current vector phase to enable a working point to move along a voltage limit elliptical boundary, breaking through inverter voltage constraint, and simultaneously carrying out feedforward decoupling compensation by combining a parameter identification result to realize smooth switching from MTPA to field weakening and stable operation in a high-speed region.

Inventors

GUO XINHUA
JIA CHAO
ZHOU SIQI

Assignees

华侨大学

Dates

Publication Date: 20260508
Application Date: 20260206

Claims (7)

1. The field weakening control method based on the self-adaptive parameter identification of the permanent magnet synchronous motor is characterized by comprising the following steps of: Collecting real voltage, current and rotating speed of a motor running in two states of i d =0 and i d <0, wherein i d is direct-axis current, acquiring a preset parameter searching range, and randomly generating a first generation particle parameter set according to the parameter searching range, wherein the first generation particle parameter set comprises a stator resistor R s , a direct-axis inductor L d , a quadrature-axis inductor L q and a permanent magnet flux linkage ; Substituting the first generation particle parameter set into an identification model, and carrying out CIPSO (computer program product storage and application) loop iteration processing by combining the acquired real voltage, current and rotating speed to obtain an optimal parameter set, wherein the optimal parameter set specifically comprises the following steps of: According to the acquired real voltage, current and rotating speed, a discrete voltage equation is used as an identification model, and the formula is as follows: , , , where k represents the kth sample, At the kth sampling in the control mode with I d =0, the direct axis voltage measurement value obtained by the actual sampling, For the electrical angular velocity at the kth sample, For the quadrature current of the kth sample in the I d = 0 mode, For the measurement of the quadrature voltage obtained by the actual sampling at the kth sampling in the control mode with I d =0, For the permanent magnet flux linkage of the kth sample in the mode I d = 0, For the kth sampled direct axis voltage in I d <0 mode, For the kth sampled direct current in I d <0 mode, For the quadrature current of the kth sample in mode I d <0, Quadrature voltage for the kth sample in I d <0 mode; substituting the first generation particle parameter set into an identification model to obtain a corresponding model estimation voltage, calculating the error square sum between the model estimation voltage and the real voltage to obtain a corresponding fitness value, and judging whether the fitness value is in a preset error range or reaches the iteration number, wherein the formula is as follows: n is the number of samples, k represents the kth sample, 、、、 Are all the weight coefficients of the two-dimensional space model, , For the kth sampling in the control mode with I d =0, the direct axis voltage estimated value and the quadrature axis voltage estimated value calculated according to the current identification parameter, , For the actual sampling of the direct and quadrature axis voltage measurements at the kth sampling in the control mode of I d <0, , For the kth sampling in the control mode of I d <0, calculating a direct axis voltage estimated value and a quadrature axis voltage estimated value according to the current identification parameters; if yes, taking the particle parameter group corresponding to the fitness value as the optimal parameter group ; If not, updating the particle speed and the position by adopting inertia weight, gaussian disturbance and asynchronous learning factors, substituting the updated particle parameter set into an identification model, calculating a corresponding fitness value, carrying out error judgment, and repeating the steps until an optimal parameter set is obtained ; Calculating the voltage vector amplitude in real time, judging the voltage vector amplitude to generate a judging result, operating an MTPA control mode when the judging result is a low-speed area mode, calculating an optimal current instruction corresponding to the low-speed area based on an electromagnetic torque equation and a Lagrangian function, and controlling the motor according to the optimal current instruction; and when the judging result is the high-speed area mode, carrying out compensation processing of the current vector angle based on the optimal parameter group, calculating to obtain an optimal current instruction corresponding to the high-speed area according to the compensated current vector angle, and controlling the motor according to the optimal current instruction.
2. The method for controlling flux weakening based on the adaptive parameter identification of the permanent magnet synchronous motor according to claim 1, wherein the update formula of the particle velocity is as follows , The updated formula of the particle position is , For the velocity of particle i at the g-th iteration, For the position of particle i at the g-th iteration, For the velocity of particle i at the g +1 iteration, For the position of particle i at the g +1 iteration, As the weight of the inertia is given, 、 Are all the learning factors of the human body, 、、、 Are all random numbers in the intervals of 0 and 1, For an individual particle to have a historical optimal position, For the global optimal position of the population, For the gaussian perturbation of particle i at the g-th iteration, Is the mean value of the two values, Is the variance.
3. The field weakening control method based on permanent magnet synchronous motor self-adaptive parameter identification according to claim 2, wherein the inertia weight of the g-th iteration Dynamically adjusting by a Sine chaotic map, wherein the formula is as follows , , , Learning factors 、 The nonlinear change update is carried out along with the iteration times, and the formula is as follows , Where g is the current iteration number, At the maximum value of the number of iterations, For the chaotic Sine map of the g-th iteration, Chaotic Sine mapping for the g-1 th iteration, As an upper limit for the weight of the inertia, As a lower limit of the weight of the inertia, For an upper limit of the individual cognitive learning factors, For the lower limit of the individual cognitive learning factors, Is the lower limit of the social cognition learning factor, The upper limit of the social cognition learning factor is that e is the base of natural logarithm.
4. The field weakening control method based on permanent magnet synchronous motor self-adaptive parameter identification according to claim 3, wherein the voltage vector amplitude is calculated in real time, the voltage vector amplitude is judged to generate a judging result, when the judging result is a low-speed area mode, the MTPA control mode is operated, and an optimal current instruction corresponding to the low-speed area is calculated based on an electromagnetic torque equation and a Lagrangian function, specifically: calculating the magnitude of the voltage vector When judging that When the electromagnetic torque equation enters a low-speed region mode, the electromagnetic torque equation is calculated based on the optimal parameter set Lagrangian function Wherein p is the pole pair number of the motor, To be a desired torque, the torque is, In order to be a lagrangian operator, Is the maximum output voltage of the inverter; And obtaining an MTPA current track equation according to the electromagnetic torque equation and the Lagrangian function: the MTPA current track equation and the electromagnetic torque equation are combined to obtain an optimal current instruction corresponding to a low-speed region , , To identify the parameter as a function of the direct current command, To identify the functional relationship of the parameters to the quadrature current command, For a straight-axis current flow, Is the quadrature current.
5. The method for controlling flux weakening based on permanent magnet synchronous motor adaptive parameter identification according to claim 4, wherein when the judgment result is a high-speed zone mode, the compensation processing of the current vector angle is performed based on the optimal parameter group, and the optimal current command corresponding to the high-speed zone is calculated according to the compensated current vector angle, specifically: When judging to When the high-speed area mode is entered, the advance angle dynamically generated by the integrator is obtained Wherein the lead angle Is proportional to the degree of voltage saturation, Is a proportionality coefficient; Inputting the optimal parameter set into an MTPA calculation module to obtain a current vector angle And based on lead angle For current vector angle Performing correction by the formula of ; According to the corrected current vector angle Calculating to obtain the optimal current instruction corresponding to the high-speed region , , Is the stator current amplitude.
6. The method for field weakening control based on permanent magnet synchronous motor self-adaptive parameter identification according to claim 5, further comprising feedforward decoupling compensation, wherein a voltage formula after compensation is as follows: , , 、 Are all output voltage commands of the current PI regulator, Is the electrical angular velocity.
7. The method for field weakening control based on permanent magnet synchronous motor adaptive parameter identification as set forth in claim 6, further comprising the step of receiving a voltage limit ellipse constraint and a current limit circle constraint when the motor is in operation, wherein the voltage limit ellipse constraint satisfies inequality under the d-q coordinate system under the simplified condition that stator resistance voltage drop is ignored This constraint is characterized in the current plane as a centered position The current limit circle constraint is that the stator current amplitude is limited by the current capacity of the inverter, and the requirement is satisfied , Is characterized by a corresponding radius taking an origin as a center in a current plane.

Description

Weak magnetic control method based on permanent magnet synchronous motor self-adaptive parameter identification Technical Field The invention relates to the technical field of motor control, in particular to a field weakening control method based on permanent magnet synchronous motor self-adaptive parameter identification. Background The Permanent Magnet Synchronous Motor (PMSM) gradually replaces the traditional asynchronous motor by virtue of the remarkable advantages of simple structure, small volume, light weight, low loss, high efficiency and the like, and becomes a preferable scheme of an industrial driving and new energy automobile power system. At the moment of the rapid development of industries such as new energy automobiles, high-end equipment manufacturing and the like, unprecedented stringent requirements are put forward on the power density, the speed regulation range and the operation efficiency of a driving motor. The built-in permanent magnet synchronous motor (IPSM) can generate a superposition effect of reluctance torque and permanent magnet torque by virtue of a salient pole effect formed by asymmetric rotor magnetic circuits, so that the torque density of the built-in permanent magnet synchronous motor (IPSM) is about 30% higher than that of a traditional asynchronous motor under the same volume, and meanwhile, the built-in permanent magnet synchronous motor (IPSM) has high mechanical strength and weak magnetic expansion potential, and becomes a preferred topology of a main drive, a high-speed main shaft and an aviation electric propulsion system of a passenger car. In order to mine the limit performance of the IPSM, the industry commonly adopts a maximum torque current ratio (MTPA) vector control strategy, and the minimum stator current under a given torque is realized by optimizing the AC-DC axis current distribution, so that copper consumption is reduced, the endurance mileage is improved, and the running efficiency is improved. However, in the actual running of the IPMSM, the stator resistance is thermally shifted under the influence of temperature, the ac-dc axis inductance shows nonlinear variation due to the magnetic saturation effect, the permanent magnet flux linkage shows demagnetizing phenomenon along with temperature rise, and the time-varying characteristics of the parameters lead to the deviation of current distribution from an optimal track, so that the problems of torque pulsation, energy efficiency reduction, dynamic response retardation and the like are caused. Furthermore, in a high-speed operation scenario, IPMSM faces more serious technical challenges. As the rotational speed increases, the back electromotive force increases linearly with the rotational speed, and when approaching the voltage limit of the dc bus of the inverter, the stator current adjustment margin decreases sharply, and if an effective adjustment mechanism is lacking, the speed regulation capability is attenuated or even out of control. The weak magnetic control technology weakens the air gap magnetic field by adjusting the direct-axis demagnetizing current, reduces back electromotive force to break through voltage constraint, and becomes a key means for expanding the rotating speed range of the motor. However, the existing flux weakening control strategy has the problems of sensitivity to parameter fluctuation, unsmooth switching between different rotating speed intervals, insufficient torque stability in a high-speed domain and the like, and restricts the realization of high-precision control in the wide-speed domain of the IPSM. The traditional control strategy is difficult to consider between dynamic response, parameter robustness and control precision, an online parameter identification method or precision influenced by noise interference or difficult to meet real-time control requirements due to complex calculation, and the stability problem of weak magnetic control under the dynamic coupling of voltage-current constraint is not solved effectively. In view of this, the present application has been proposed. Disclosure of Invention The invention provides a field weakening control method based on permanent magnet synchronous motor self-adaptive parameter identification, which can at least partially improve the problems. In order to achieve the above purpose, the present invention adopts the following technical scheme: a field weakening control method based on permanent magnet synchronous motor self-adaptive parameter identification comprises the following steps: Collecting real voltage, current and rotating speed of a motor in two states of i d =0 and i d <0, wherein i d is direct-axis current, acquiring a preset parameter searching range, and randomly generating a first-generation particle parameter set according to the parameter searching range; Substituting the first generation particle parameter set into an identification model, and carrying out CIPSO (CIPSO loop iteration) processing by co