Fine Analysis Of High Speed Motor Loss Based On Time-step Finite Element Method

In order to realize the fine analysis of motor loss in the manufacture of high-speed motor,it is vital to explore the loss calculation model that can take into account the influence of various nonlinear and complex structures,and further study the relationship between higher harmonics and high-speed motor loss.In this thesis,the high-speed motor loss model is improved from the stator and rotor iron loss and stator and rotor copper loss.The loss calculation and experimental research are carried out with 37kW,300Hz high-speed motors as prototypes,and the detailed analysis of internal loss of high-speed motor is also carried out.The main works are as follows:1.Taking a 37kW,300Hz motor as an example,calculate and refine the iron loss of the stator and rotor and starting performance under no-load and full-load conditions,based on the improved high-speed motor loss model,then analyze the features of the fundamental and harmonic flux density generated by the harmonic current in the air gap.Compared with the traditional motor loss calculation model,these calculation results verify the rationality and accuracy of the new model.2.Applying different high-order harmonic voltages to the initial motor voltage based on the simulation model,this article analyzes and compares the characteristics of the flux density distribution of the typical position of the stator core,calculates and refines the iron loss and copper loss of the stator and rotor.The distribution characteristics of the rotor core are compared with the high-speed motor loss calculation model,to distinguish the advantages and disadvantages,and provide analysis and guidance for the inverter high-speed motor loss model.3.Based on the established time-step finite element motor loss model,this article calculates and analyzes the distribution characteristics of air gap magnetic field in the variation of different rotor slot height and width,and conducts a study on their influences on the stator and rotor copper loss,iron loss,total loss,starting performance.At the same time,the semi-closed slot effect produced by the closed slot of the high-speed motor rotor is analyzed in depth.