Topology Analysis And Optimization Design Of Permanent Magnet Synchronous Machine

Permanent magnet synchronous machine(PMSM)is a type of energy-saving and environmentally friendly machine with great development potential and application prospects.Its topological structure is diverse and has a wide range of applications.It has many advantages such as small size,light weight,high power density,high efficiency,and wide speed range.It has been increasingly used in industrial production and daily life.It is of great significance for upgrading the machine industry,reducing production costs and energy saving to study the basic theory and design rules of PMSM,analyze the impact of different stator and rotor topologies on machine performance,optimize the machine based on existing research results and engineering needs,and develop high-performance and low-cost PMSM products.This paper systematically studied PMSM,including its basic theory,stator winding,rotor pole structure and optimization design.the specific contents are as follows:(1)The basic theory of PMSM is studied,including its basic structure and operating principle,vector relationship and mathematical model,and common control strategies.An inductance calculation method considering the change of PM flux is introduced,and the influence of current changes on the inductance is analyzed.(2)The design rules of pole number and split ratio of PMSM are studied,and the machines with different pole numbers are designed and compared;The common winding forms of PMSM are studied,including integer slot distributed winding,fractional slot distributed winding and fractional slot concentrated winding.The characteristics of different winding forms and poleslot combinations are analyzed from the aspects of winding coefficient,magnetomotive force harmonics and cogging torque.The machines with different winding types and pole-slot combinations are designed and compared,and the effects of winding layers and rotor structure are also studied.(3)The common rotor magnetic pole structure of PMSM is studied.Based on the equivalent magnetic circuit,the rotor magnetomotive force and the inductance parameters of different magnetic pole structures are analyzed.Five kinds of PMSM with different rotor magnetic pole structures are designed and their electromagnetic performances are compared and analyzed,which provides a reference for the selection of different rotor pole structures.(4)An optimized design of a 30 k W PMSM for electric vehicles is proposed.The optimization scheme using fractional slot single-double-layer hybrid winding and (?)-type rotor pole structure is proposed and compared with the existing scheme.The results show that the optimization scheme can effectively increase the power density and reduce the volume and cost of the machine.