关键词: 变频调速电机, 轴承电蚀损伤, 绝缘轴承优化设计, 改进NSGA-Ⅱ算法

Abstract: Aiming at the problem of premature failure of variable frequency speed regulation motors bearing due to the non-standardization of insulation layer thickness,the effect of adding insulating layer on electric corrosion damage of motor bearing was analyzed.On this basis,a multi-objective optimization model of insulated bearing was established,and an improved NSGA-Ⅱ was proposed to conduct the corresponding efficient solution.Based on the electromagnetic field and circuit simulation analysis,the influence law of the thickness of the insulating layer on the shaft current of the insulating bearing was revealed,and the three optimization objectives of fatigue life,corrosion life and surface hardness of the insulating layer were set up.The population individual was constructed based on the structural parameters of the insulating bearing,and several improved strategies including the expansion of the initial population size,the weight removal of the mating pool and Arithmetic mutation operator were introduced to increase the population diversity.A numerical example with insulated bearing of metro traction motor was demonstrated to show the rationality and superiority of the proposed optimization design method,where the related performance indicators are improved after optimization.

Key words: variable frequency speed regulation motor, electric corrosion damage of bearing, optimal design of insulated bearing, improved NSGA-Ⅱ