Research On Double-air-gap Composite Motor Integrated With Permanent Magnet And Reluctance Resolver

Modern computer numerical control(CNC)machine tools,intelligent appliances,robots and other high-end equipment require the motor drive system to have the ability of absolute position detection of rotor.In order to solve the technical problem that traditional synchronous machine and sensorless control can not realize the absolute position detection,a compact and reliable dual-gap composite machine topology is studied from the perspective of machine topology.The structure is composed of permanent magnet synchronous machine(PMSM)and variable reluctance resolver(VRR).Using the reasonable combination of pole pairs,the absolute position sensorless control of the machine rotor is realized while improving the power density of the machine system.The main research of this article is as follows:Firstly,the topological characteristics of the dual-gap composite machine are analyzed.Then the basic principle of the mechanical position estimation method of the rotor of dual-gap composite machine is revealed.The electromagnetic design scheme of the machine is given based on the specific index.And the 2D finite element analysis(2D FEA)of the machine is carried out by using the finite element simulation software to verify the rationality of the design scheme.Secondly,aiming at the dual-gap composite machine composed with PMSM and VRR,the structural characteristics of VRR with outer rotor are analyzed.The design scheme of VRR with outer rotor is given,and the design method of VRR is elaborated from three aspects: slot-pole combination,winding arrangement and air-gap function.Thirdly,based on the modified winding function approach(MWFA),the equivalent magnetic circuit model of the VRR with outer rotor is established.Through the derivation of the MWFA,the analytical calculation method of the electromagnetic parameters of the VRR is obtained.The finite element simulation model of VRR is established,and the analysis calculation results and the ability of rotor position detection are verified by FEA.Finally,considering the complex special structure of the dual-gap composite machine and the limitation of processing conditions,the structure design scheme of the prototype is given.And the structural analysis of main components of the prototype is carried out to verify the rationality of the structure design.On this foundation,an experimental platform is built to test the prototype at different speeds,and the experimental results are analyzed to verify the feasibility of the prototype design.