Research On Field-circuit Coupled Simulation Design Of Permanent Magnet Synchronous Motor

Electrical machines and drives are a key technique for electric vehicle(EV)application.Permanent magnet synchronous motors(PMSMs)have been widely used in EV traction systems due to their superiorities,such as high efficiency and high power density.Efficient and reliable simulation design for EV motor drive system has become a focus of current researches.This paper investigates the field-circuit coupled simulation design for vector control of PMSM,and the main work is as follows:Firstly,the mathematical model and control system of interior PMSM,the vector control theory,and the flux-weakening strategies are discussed.Secondly,the simulation design methods using MATLAB/Simulink and finite-element method(FEM)for PMSM system are studied,and their respective advantages and disadvantages are analyzed.MATLAB/Simulink can achieve accurate control algorithm modeling,while it is hard to accurately analyze the inherent motor characteristics.FEM can achieve precise analysis for the motor performance,but it is unable to comprehensively analyze the system performance under different control strategies.Then,a design and analysis method for PMSM vector control system based on field-circuit coupled time-stepping FEM is presented.The coupled simulation model is built in ANSYS Maxwell and Simplorer,which integrates the electromagnetic field model for PMSM and the control circuit model.Detailed design process is described.Collaborative simulations are conducted to study the starting process and operating characteristics of the motor.Finally,based on the field-circuit coupled simulation model,a design method of the current lookup table(LUT)for PMSM system efficiency optimization is proposed.Field-circuit coupled simulations are carried out on a 15-kW PMSM prototype,and the current command LUT is designed for optimal system efficiency.This optimal LUT is applied in the experiments,and the simulation and experimental results show a good consistency,which proves the validity and practicability of the proposed design method.