Effects analysis of misalignments on dynamic characteristics test for permanent magnet synchronous motor

Permanent magnet synchronous motor (PMSM) has been widely used in industrial fields. In order to get the performance of PMSM, test of the machine must be executed. More and more applications have started pay attention to the dynamic performance of PMSM. During the dynamic characteristics test of PMSM, the accuracy of the test results affected by misalignments which could affect the useful life of measuring device, and even destroyed the test equipment. In this paper it use the dynamics simulation software to study the characteristics of torque ripple which generated by the misalignments in the dynamic test of the PMSM. It could be provide the basis for separating the toque ripple caused by the misalignments. Simulation results show that with the presence of a parallel misalignment in shafting, the transmitted torque value of parallel misalignment part will be superimposed a sinusoidal torque component. The frequency of the superimposed sinusoidal amount is equal to the frequency of shaft rotational. The amplitude is proportional to the amount of parallel misalignment. The initial phase has relationship with the location of misalignment amount. All of them have nothing do with the value of transmitted torque. Finally, the experimental result verified the accuracy of simulation results.