Effect Of Magnetostriction On Vibration And Noise Of Permanent Magnet Synchronous Motor

The power sources that cause the electromagnetic noise of permanent magnet synchronous motor include electromagnetic force and magnetostrictive force.In the previous research on the vibration and noise of permanent magnet synchronous motor,Maxwell’s electromagnetic force is generally considered as the main power source of the electromagnetic vibration and noise of permanent magnet synchronous motor.With the continuous improvement of the requirements for the vibration and noise of permanent magnet synchronous motor,the numerical simulation is required to be closer to the actual operation of the motor,The effect of magnetostriction on the vibration and noise of PMSM must be considered in the simulation.Firstly,the complete electromagnetic field theory of PMSM is introduced,including the theory of the influence of permanent magnet field,winding field and slotting effect on permanent magnet field and winding field,and the magnetic density curve under different conditions is obtained by programming with MATLAB software;then,it is compared with the result of Ansoft simulation to verify the correctness of the theory;finally,according to the results of Wheat The electromagnetic force is calculated by the Maxwell stress method,and the data of the electromagnetic force and the harmonic component of the electromagnetic force vary with time and space are obtained respectively.Then,through the modal analysis of the stator and the stator shell assembly of the motor by ANSYS,the first six modal shapes and natural frequencies are calculated to prevent the natural frequency of the motor structure from approaching the radial electromagnetic force frequency in the air gap,avoid resonance,intensify the electromagnetic vibration noise of the motor,damage the hearing of people,damage important mechanical equipment,and can be in the motor design stage The resonance phenomenon can be avoided by optimizing the structure of the motor.Finally,the magneto mechanical coupling model of stator core considering magnetostrictive effect is established,and the electromagnetic force density and magnetostrictive force density are calculated.The stator vibration displacement,vibration velocity,acceleration and sound pressure distribution are calculated.The results are compared with the vibration and noise response of the stator core under the electromagnetic force alone.When considering the magnetostriction effect,the radial force density amplitude of the stator teeth increases by 13%compared with that under the electromagnetic force alone,the deformation of the stator core increases by 13.4%compared with that under the electromagnetic force alone,and the vibration speed,acceleration and sound pressure level also increase significantly,indicating that magnetostriction The effect has an important contribution to the vibration and noise of the motor,and the simulation error of the motor noise is smaller and closer to the actual measurement value when the magnetostrictive effect is considered.Therefore,the effect of magnetostriction cannot be ignored in the research and design stage of low noise permanent magnet synchronous motor.