Iron Loss Analysis Of Stator Permanent Magnet Motor And Development Of Finite Element Simulation Software Platform

In this paper,the stator permanent magnet motor is taken as the research object,the influence of DC bias on the iron loss of motor and the development of finite element analysis software for motor are studied.The main research results of this paper are summarized as follows:Finite element analysis and iron loss calculation are carried out for stator permanent magnet motor.The development of the stator permanent magnet motor and working principle of three typical stator permanent magnet motor are introduced.The finite element analysis of stator permanent magnet motor,represented by magnetic flux switching motor and double salient pole permanent magnet motor,is carried out.The magnetic flux density waveform of the two motors is compared and analyzed.It is found that there is obvious DC bias in the operation of stator permanent magnet motor.In addition,the electric motor iron loss models are reviewed and four traditional iron loss calculation models are introduced in detail.The iron loss coefficient of 50W470 silicon steel sheet is measured by Epstein’s square circle and the iron loss of a 12/10 pole magnetic flux switching motor is calculated by JMAG and ANSYS.The effect of DC bias on the iron loss of motor is studied.Firstly,two classical partial magnet loss models are introduced.Then a multifunctional power supply is used to provide alternating current with DC bias magnetic field to Epstein square circle.In addition,a multifunctional power supply is used to provide alternating current with DC bias to the Epstein square circuit.Based on the experimental results,the defects of the traditional iron loss models are found.An improved iron loss model,which considers DC bias,is proposed based on the traditional DC-biased iron loss model.The improved model is applied to the motor finite element simulation software EMFEA(Electric Machine Finite Element Analysis),which is developed by the team of professor Cheng Ming in Southeast University,to calculate the iron loss of the 12/10 pole flux switching motor.The calculated result of the improved model is 9.00% higher than that of the model without considering magnetic bias.Finally,the iron loss experiment is carried out to verify the accuracy of the model.A finite elemnent software package of electrical machines is developed by FEPG(Finite Element Program Generator)software,and the GUI(Graphical User Interface)of the software is worte by Qt Creator.Firstly,the finite element method and FEPG software are introduced.Secondly,the detailed process of FEPG generating two-dimensional electromagnetic field finite element source program is introduced.Thirdly,the generated source program is modified to realize the function of antiperiodic boundary,arbitrary angle rotation of the rotor,calculation of magnetic linkage and torque,calculation of partial magnet consumption.Then,the GUI of EMFEA is introduced in detial.Finally,the software EMFEA is compared with JMAG to verify the reliability of the calculated results.