CN-121978522-A - Permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection

CN121978522ACN 121978522 ACN121978522 ACN 121978522ACN-121978522-A

Abstract

The invention discloses a permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection, which comprises the steps of calculating a sideband common-mode voltage injection range and sideband harmonic voltage frequency components under injection according to a sideband harmonic voltage model; the method comprises the steps of calculating the frequency component of the sideband harmonic current with the largest amplitude after injection in the common-mode voltage injection range, taking electromagnetic waves generated by the sideband harmonic current under the condition as a vibration excitation source, ascending the switching frequency according to a specific step length, carrying out sweep frequency experiments, analyzing collected data, correcting a frequency response curve according to a high-frequency electromagnetic force calculation function, and obtaining modal parameters of the motor. According to the invention, the common-mode voltage which has no influence on the fundamental frequency current is injected into the closed-winding permanent magnet synchronous motor, and the sideband harmonic current component with the largest amplitude after injection is selected as the vibration excitation source frequency sweep, so that the identification of the high-frequency mode of the motor is effectively realized. The method can be widely applied to the field of motor mode identification.

Inventors

KONG WUBIN
YANG GUANG
GUO HAIFENG
GE JIAN
YANG JUN
GU MINGLEI
Geng pan
WANG ZHIQIANG

Assignees

华中科技大学

Dates

Publication Date: 20260505
Application Date: 20260122

Claims (9)

1. A permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection is characterized by comprising the following steps: Calculating the injection range of the sideband common mode voltage according to the sideband harmonic voltage model; In the sideband common mode voltage injection range, calculating the sideband harmonic current frequency component with the largest amplitude after injection, and taking electromagnetic force generated by sideband harmonic current under the condition of common mode injection as a vibration excitation source; setting working conditions and sideband harmonic frequencies, and carrying out sweep frequency experiments by combining the vibration excitation source; analyzing according to the data of the sweep frequency experiment to obtain an original frequency response curve; and correcting the original frequency response curve according to the high-frequency electromagnetic force calculation function, and outputting the modal parameters of the motor.
2. The high-frequency modal identification method of a permanent magnet synchronous motor based on common-mode voltage injection according to claim 1, wherein the expression of the sideband common-mode voltage injection range is as follows: Wherein, the Representing the sum of the duty cycles of the SV0 and SV7 vectors, Representing the injected common mode voltage reference value over the switching period, Representing the two-phase on-effective vector duty cycle, Representing the single-phase on-active vector duty cycle, For the dc bias to be applied to the substrate, Is the 3-order common mode harmonic modulation ratio, Is the fundamental angular frequency.
3. The method for identifying the high-frequency mode of the permanent magnet synchronous motor based on common-mode voltage injection according to claim 2, wherein the sideband harmonic current frequency component with the largest amplitude after injection is calculated according to the following formula: Wherein, the Representing the amplitude of the injected rear sideband harmonic current, Representing the units of an imaginary number, Which represents the angular frequency of the light emitted by the light source, Representing an inductance matrix of the device, Representing a sideband harmonic current phasor matrix, The time step is indicated as such, The voltage phasors for the A, B, C phases are shown separately, The current phasors for the A, B, C phases are shown separately, Representing the transposed symbol, The voltage rotation space vector is represented as, Representing the current rotation space vector.
4. The method for identifying the high-frequency mode of the permanent magnet synchronous motor based on common-mode voltage injection according to claim 2, wherein the calculation formula of the electromagnetic force is expressed as follows: Wherein, the Representing the total radial concentration of the electromagnetic force, Represents a radially concentrated electromagnetic force, Representing a radially concentrated electromagnetic couple, Is the distance between the grooves, and the distance between the grooves is equal to the distance between the grooves, Is the tooth height of the stator, and the tooth height of the stator is equal to the tooth height of the stator, For the stator yoke to be wide, For the effective length of the motor, Is the inner diameter of the stator, Is the width angle of the tooth surface of the stator, Is the first The position of the center line of each stator tooth, Represents the radial component of the sideband electromagnetic force density, Representing the tangential component of the sideband electromagnetic force density.
5. The method for identifying high-frequency modes of a permanent magnet synchronous motor based on common-mode voltage injection according to claim 4, wherein the step of setting working conditions and sideband harmonic frequencies and carrying out sweep frequency experiments by combining the vibration excitation source specifically comprises the following steps: Fixing the rotating speed, increasing the switching frequency from low to high according to a specific step length, setting sideband harmonic frequency according to the switching frequency, and carrying out sweep frequency experiments by combining the vibration excitation source; and recording working conditions and data of the sweep frequency experiment.
6. The method for identifying high frequency modes of a permanent magnet synchronous motor based on common mode voltage injection according to claim 5, wherein the step of analyzing according to the data of the sweep experiment to obtain an original frequency response curve comprises the following steps: Extracting an acceleration frequency response curve corresponding to the vibration excitation source; the vibration mode of the motor is positioned when resonance is induced under the action of a vibration excitation source.
7. The method for identifying high frequency modes of a permanent magnet synchronous motor based on common mode voltage injection according to claim 6, wherein the step of correcting the original frequency response curve according to a high frequency electromagnetic force calculation function and outputting mode parameters of the motor specifically comprises the following steps: Fitting the calculation result of the high-frequency electromagnetic force with an original frequency response curve of a corresponding vibration excitation source to obtain a corrected frequency response curve; and generating modal parameters of the motor based on the corrected frequency response curve.
8. A permanent magnet synchronous motor high-frequency mode identification system based on common-mode voltage injection is characterized by comprising: The vibration excitation determining unit is used for calculating a sideband common mode voltage injection range according to the sideband harmonic voltage model, calculating the sideband harmonic current frequency component with the largest amplitude after injection in the sideband common mode voltage injection range, and taking electromagnetic force generated by the sideband harmonic current under the condition of common mode injection as a vibration excitation source; the sweep frequency test unit is used for setting working conditions and sideband harmonic frequencies and carrying out sweep frequency experiments by combining the vibration excitation source; the vibration analysis unit is used for analyzing according to the data of the sweep frequency experiment to obtain an original frequency response curve; And the identification unit is used for correcting the original frequency response curve according to the high-frequency electromagnetic force calculation function and outputting modal parameters of the motor.
9. Permanent magnet synchronous motor high frequency mode identification device based on common mode voltage injection, characterized by comprising: At least one processor; At least one memory for storing at least one program; When the at least one program is executed by the at least one processor, the at least one processor is caused to implement a permanent magnet synchronous motor high frequency mode identification method based on common mode voltage injection as claimed in any one of claims 1-7.

Description

Permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection Technical Field The invention relates to the field of motor mode identification, in particular to a permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection. Background In steady state operation of a permanent magnet synchronous motor, accurate analysis of a high-frequency mode is an important premise for calculating and inhibiting high-frequency vibration of the motor, current acquisition of motor mode parameters mainly depends on a hammering mode experiment method, and in the process of using an exciting force hammer for experiment, a medium-low frequency mode of the motor can be well identified, however, energy in a high-frequency range is rapidly attenuated and difficult to excite and identify the high-frequency mode due to the limitation of hammer head materials and the bandwidth of a hammer head force sensor, errors are reduced in a mode of repeated experiments for many times, complexity in the experiment process is increased, and the method is not suitable for identification of the high-frequency mode. The mode experiment is paid attention to because the mode experiment can be actively regulated and controlled by a method of electromagnetically exciting the motor to vibrate. The excitation source is controlled by utilizing the electromagnetic field, and excitation force with specific frequency and amplitude can be accurately applied, so that the wide-frequency-domain modal characteristic of the motor is better covered. However, the additional electromagnetic excitation source can obviously increase the cost and complexity of the system, electromagnetic waves generated by sideband current harmonic waves excited by the motor are used as endogenous electromagnetic excitation sources for motor vibration, and the method can effectively acquire motor modes under certain working conditions, but the current amplitude of the endogenous current harmonic waves is not necessarily obvious along with the change of the working conditions, and in addition, part of low-order modes (such as a first-order bending mode of a stator) or local modes (such as an end cover mode) are sensitive to excitation energy, and high-order modes or weak-coupling modes need enough excitation energy to be effectively excited. The adoption of the endogenous current harmonic wave as an excitation source can cause the problems of low signal-to-noise ratio, high-order modal loss and the like, and cannot meet the modal excitation requirement. Therefore, the research of the high-frequency mode identification method using the internal electromagnetic excitation source with adjustable amplitude is of great significance to the comprehensive and accurate mode identification of the motor. Disclosure of Invention In view of the above, in order to solve the technical problem that in the existing permanent magnet synchronous motor mode identification method, electromagnetic waves generated by sideband current harmonic waves excited by a motor are used as an endogenous electromagnetic excitation source for motor vibration, so that mode identification precision is low, the invention provides a permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection, which comprises the following steps: According to the sideband harmonic voltage model, calculating the sideband common mode voltage injection range and the sideband harmonic voltage frequency component under injection; Calculating the sideband harmonic current frequency component with the largest amplitude after injection in the common-mode voltage injection range, selecting the common-mode injection condition, and taking electromagnetic waves generated by the sideband harmonic current under the condition as a vibration excitation source; The switching frequency is increased from low to high according to a specific step length, and the step length can be properly reduced for the frequency range inducing resonance to carry out fine frequency sweep; Analyzing the acquired data, and correcting the frequency response curve according to the high-frequency electromagnetic force calculation function to obtain the modal parameters of the motor. Based on the scheme, the invention provides a permanent magnet synchronous motor high-frequency mode identification method based on common-mode voltage injection. The specific direct current bias and the third harmonic common mode component are injected into the modulated wave, so that the output frequency spectrum reconstruction of the inverter is realized, the specific frequency peak is enhanced, the frequency sweep is completed, and the motor mode is accurately identified. By means of accurate regulation and control of common mode voltage injection, the method can efficiently realize accurate identification of the permanent magnet synchronous