Research On Vibration And Noise Of Vehicle Permanent Magnet Synchronous Motor Based On Repetitive Control

With the improvement of people’s environmental awareness and living standard,new energy vehicles have gained popularity and recognition due to their advantages in the field of environmental protection and energy saving.The vibration noise of the interior permanent magnet synchronous motor permanent magnet synchronous motor,as the first choice of pure electric vehicle drive motor,plays a decisive role in the NVH performance of electric vehicles,so the analysis and optimization of the vibration noise of the interior permanent magnet synchronous motor permanent magnet synchronous motor has become an urgent problem for electric vehicles.This paper takes permanent magnet synchronous motor for electric vehicles as the research object,and proposes a low-noise control strategy based on fractional-order sixfold repetitive controller for the current research status of motor vibration noise and harmonic suppression control strategy by scholars at home and abroad.The main research contents are as follows:Firstly,a brief introduction to the basic theory of permanent magnet synchronous motor and the corresponding control algorithm is given.Two types of rotor structures of permanent magnet synchronous motors are described,and the mathematical model of the motor in the synchronous rotating coordinate system is derived using the coordinate transformation principle for the characteristics such as strong nonlinearity of the mathematical model in the three-phase stationary coordinate system.Then the advantages and disadvantages of the traditional repetitive control as well as two vector control algorithms are presented and analyzed.Secondly,the effect of permanent magnet insertion on the air gap magnetic field and the relationship between radial electromagnetic force wave and winding current of automotive permanent magnet synchronous motor is investigated.Considering the interior permanent magnet synchronous motor with embedded permanent magnets,the air gap specific permeability function is added to the compensation function brought about by the convex pole effect in the analysis process,and the air gap magnetic field harmonic content of the interior permanent magnet synchronous motor and the Surfacemounted permanent magnet synchronous motor is calculated.And the radial electromagnetic force caused by the ideal current and the additional electromagnetic force wave caused by the harmonic current are analyzed respectively.It is found that the spatial order of the radial electromagnetic force wave is mainly the even multiple of the motor pole pair,and the relationship between the low-order radial electromagnetic force wave and the harmonic current is obtained.Thirdly,a low-noise control strategy for automotive permanent magnet synchronous motors based on an improved fractional-order repetitive controller is proposed.For the situation that the resonant frequency of the conventional repetitive controller is easily shifted,a joint design of elliptic filter and all-pass filter is proposed to approximate the fractional-order delay link,so as to improve the frequency adaptability of the controller.By designing the compensation link,the robustness of the control system in the operating frequency band is improved.The constructed joint simulation verifies that the proposed control strategy can effectively suppress the current harmonics and reduce the radial electromagnetic force wave amplitude.Finally,the experimental test platform was built and experiments were conducted.The experimental data of the motor before and after the improvement of the control strategy were tested.By comparing the current waveforms before and after the control strategy improvement and the vibration data in the vertical direction of the end under two working conditions,it was verified that the control strategy based on the fractional order repetitive controller can effectively suppress the current harmonics and reduce the vibration and noise of the motor.