Research On Multi-objective Comprehensive Optimization Method Of High Power Contactor

In recent years,the annual volume of high-power contactor is increasing rapidly,and the optimization design of high-power draws the attention of people.Orthogonal experimental method is the most common method use d in contactor optimization.This method is hard to obtain the global optimal solution,and focuses more on single objective optimization.Many targets of high-power contactor can be optimized,including dynamic characteristics,coil power and so on.It is a typical multi-objective optimization problem.Therefore,this paper takes the straightlyacting high-power contactor as an example to study the multi-objective optimization method.The multi-objective optimization need to repeatedly get the target value,and finite element method which is used to calculate the dynamic characteristics of the target value of the contactor is time-consuming.According to the theory of the magnetic circuit and approximate model two different fast algorithms are proposed in this paper.Based on the fast algorithm and the multiobjective optimization method,the multi-objective optimization design of predictable high-power contactors is completed.The finite element method is the most common method of contactor simulation analysis,and the fast algorithm is also needed the finite element method to provide the data base.The dynamic characteristics and temperature are regarded as two independent problems when solved by the finite element method.However,the electromagnetic and heat are interactional in the process of simulation.To obtain the finite element simulation results more accurate,this paper analyzes the mutual influence between the temperature and dynamic characteristics.An electromagnetic thermal coupling simulation model is set up by the joint simulation of FL UX and Matlab/Simulink.At last the simulation results are contrasted with the measured data.To achieve fast calculation of dynamic characteristics,this paper analyze s the error analysis of the magnetic circuit method to study the improved magnetic circuit method.According to the effect of temperature on the magnetic circuit,the magnetic circuit method is improved to calculate the dynamic characteristics under different temperature of contactor.Because of the high requirements of modeling ability and inherently low universality of magnetic circuit method.Another fast calculating method of dynamic characteristics based on radial basis function s neural network is put forward.In the end,the scope of the two methods is defined by comparison.Then,the performance of particle swarm optimization(PSO)and differential evolution algorithm(DE)is compared and analyzed.And the multi-objective optimization method based on particle swarm optimization is studied.At the same time,an entropy weight ideal point method is put forward,to determine the degree of importance of each optimization objective.By this method,the problem that each optimization objective is difficult to reach the optimum at the same time is solved.Finally,the multi-objective optimization method is adopted to optimize the four goals of the high-power contactor,including response time,holding force,coil power and armature quality.After optimization,the holding force increased by 28%.The coil power decreased by 6%.And the other targets remained the same.The practicability of the multi-objective optimization method was proved.