Modeling And Characteristic Analysis Of Surface-mounted And Interior Hybrid PMSM

The traditional surface-mounted permanent magnet motors(SPM) own faster dynamic response and smaller torque ripple, suitable for sevo drive, but its power density is lower. The traditional interior permanent magnet motors(IPM) own higher power density and stronger overload capacity, but bigger torque ripple and too much leakage flux, the magnetic separation bridges are present to reduce the mechanical strength. This paper proposes a surface-mounted and interior hybrid permanent magnet synchronous motor(SIHPMSM) with a new structure containing surface-mounted permanent magnets and interior permanent magnets, the new sreucture can reduce the leakage flux, remove the magnetic bridge, enhance the mechanical strength and own strong overload capacity.This paper adopts equivalent magnetic circuit method to research the characteristics of the SIHPMSM, the equivalent magnetic circuit models(EMCMs) of the SIHPMSM in open circuit and loaded situation are established respectively; through omitting the magnetic circuits leakage and the iron cores saturation effect, the simplified EMCMs are established respectively to solve the distribution of air-gap magnetic field,the back-EMF and magnetic flux linkages of stator armature windings; the simplified EMCMs of direct axis and quadrature axis considering armature reaction are established respectively to solve the distribution of the air-gap magnetic field in open circuit and loaded situation, the armature back-EMF and the output electromagnetic torque; the finite element models(FEMs) are also established to analyze the characteristics of the SIHPMSM; combining with the results of the simplified EMCMs and FEMs, the rationality and validity of the EMCMs are verified. The cogging torque mathematical models of SIHPMSM based on energy method are established, through analyzing the parameters influencing the peak value of the cogging torque, the different methods are proposed to optimize the cogging torque of the SIHPMSM, the magnet shifting method is vertified to be the most effective method by comparing to the simulation results of the FEMs of the SIHPMSM, and the simulation results of the various electromagnetic performance of the SIHPMSM before and after optimized are also compared. This paper calculates and solves the temperature field parameters of each part of theSIHPMSM based on the structure characteristics, then the temperature field FEMs are established, the stable temperature rise of the SIHPMSM in rated operating condition are obtained by solving the FEMs, which will provide a basis for the cooling system improvement of the SIHPMSM. The experimental platform of the SIHPMSM is established, and the operation characteristics of the SIHPMSM in different loaded conditions are obtained by testing, the excellent performance of the SIHPMSM is Preliminary verified.