Optimization Analysis of Inherent Shaft Voltage in Line-Start Permanent Magnet Synchronous Motor

This paper analyzes the inherent shaft voltage in line-start permanent magnet synchronous motor (LSPMSM). The magnetomotive force of per permanent magnet along the circumference of air gap is transformed into the distributed magnetomotive force. The analytical expression of shaft voltage is deduced. Rotor teeth width design and rotor teeth pairing design aimed at reduction of shaft voltage are studied on the basis of the equivalent magnetomotive force. Furthermore, several LSPMSM models are investigated by the finite element analysis (FEA) to verify the effectiveness of theoretical analysis.