Analysis of electromagnetic vibration of IPM motor based on vector control for electric propulsion ships

An overall investigation of the electromagnetic force, vibration, and average torque of the Interior Permanent Magnet Synchronous Motors (IPMSM) in the dq model for electric propulsion ships is carried out, and the electromagnetic vibration characteristics of the PMSM under the vector control strategy is explored. Firstly, the space and frequency characteristics of the electromagnetic force of the dq model motor are derived using the Maxwell stress tensor method, and the influence of the dq-axes magnetic field on the electromagnetic force under different loads is discussed in detail. Secondly, the finite element method is used to verify the influence of dq-axes currents on motor electromagnetic force, vibration, and average torque. Finally, the experiments are conducted on an 8-pole 48-slot IPMSM, and the results are consistent with the theoretical analysis and simulation results. The results indicate that the electromagnetic vibration of the PMSM for electric propulsion ships increases with the increase of the current i_q and decreases with the increase of the current i_d. The electromagnetic vibration of the motor can be reduced by selecting the appropriate dq-axes current under the output torque constraint.