Design And Optimization Of A Gramme-ring-winding High-speed Slotless Permanent-magnet Motor

Due to the advantages of high power density,high efficiency,high rotor strength,high-speed permanent-magnet motor is widely favored in high-speed industrial application.Based on the application background of the fuel cell centrifugal compressor,a gramme-ring-winding high-speed slotless permanent magnet motor with non-magnetic fillers in stator is presented to solve the serious overheating problem of the high-speed permanent magnet rotor in this dissertation.Based on multi-physics field theory,the comprehensive design and optimization of the motor are studied.The specific research works consists of the following aspects:(1)Combined with the key technical requirements of high-speed permanent magnet synchronous motors,the design difficulties and key points of the motor in this dissertation are analyzed.Based on the perspectives of electromagnetic performance,heating,rotor strength and dynamics,the preliminary dimensions and material selection of key components of motor stator and rotor are designed and analyzed,and a preliminary design scheme is established.(2)In order to pursue high power density and high efficiency,comprehensively considering the performance requirements and constraints of multi-physics field,a motor optimization design model based on the NSGA-Ⅱ optimization algorithm is established to realize the rapid optimization design of motor,The optimal parameter matching design scheme of the motor is determined and the parameter sensitivity analysis is carried out.(3)The CFD analysis model of the temperature field of the gramme-ring-winding high-speed slotless permanent-magnet motor is established,and the modeling method of Litz wire gramme ring-winding is studied.On this basis,the temperature field analysis is carried out to clarify the temperature distribution characteristics of the motor,and the cooling improvement is carried out for the high-risk parts near or even exceeding the temperature rise limit.In this paper,by changing the non-magnetic spacer material,Achieve effective reduction of temperature rise.(4)The basic line type and preliminary selection of the Litz wire are given.The loss classification and calculation method of Litz wire gramme ring-winding are studied,The characteristics of winding loss and its relationship with line type and size parameter are summarized.Finially,an optimization design method of Litz wire aiming at the optimal temperature is proposed,and the optimization analysis was carried out and the design scheme of Litz wire was established.