Analysis on Solid Rotor 3-D Temperature Field in High Voltage PMSM

For estimating the working temperature distributions in high voltage power permanent magnet synchronous motors（PMSM） accurately,a 315 kW 6 kV line-starting PMSM was investigated in this paper.Taking the losses obtained from the 2-D electromagnetic analysis as the heat sources,the physical and mathematical models for 3-D solid rotor temperature field analysis were established.Considering the complex structure of rotor end components,the heat transfer coefficients of end surfaces were obtained by using the method of inverse iteration.After proposing the basic assumptions and associated boundary conditions,the temperature field was solved by using the 3-D FEM.The obtained results show good agreements with the test data,and the calculation satisfies the requirements well.The new method for determining the heat transfer coefficients supply a reference for the calculation of surface heat transfer of PMSM.