In order to improve the thrust-power ratio index of the linear induction motor(LIM), a novel adaptive genetic algorithm (NAGA) is proposed for the design optimization of the LIM. A good-point set theory that helps...In order to improve the thrust-power ratio index of the linear induction motor(LIM), a novel adaptive genetic algorithm (NAGA) is proposed for the design optimization of the LIM. A good-point set theory that helps to produce a uniform initial population is used to enhance the optimization efficiency of the genetic algorithm. The crossover and mutation probabilities are improved by using the function of sigmoid and they can be adjusted nonlinearly between average fitness and maximal fitness with individual fitness. Based on the analyses of different structures between the LIM and the rotary induction motor (RIM) and referring to the analysis method of the RIM, the steady-state characteristics of the LIM that considers the end effects of the LIM is calculated and the optimal design model of the thrust-power ratio index is also presented. Through the comparison between the optimal scheme and the old scheme, the thrust-power ratio index of the LIM is obviously increased and the validity of the NAGA is proved.展开更多
Linear machines(LMs)produce linear motion without any intermediate transmission mechanisms,thus the whole electromechanical system has simple structure and its efficiency is high.Because of such merits,linear machines...Linear machines(LMs)produce linear motion without any intermediate transmission mechanisms,thus the whole electromechanical system has simple structure and its efficiency is high.Because of such merits,linear machines have been studied for a long time and rapidly developed in recent years.Due to the characteristic of open structure,linear machines have more diversity than rotary machines in terms of machine topologies.Accounting for the wide applications of linear machines,e.g.Maglev train,precision machine tools,semiconductor processing device,automatic equipment,logistic transport line,ropeless lifter,compressor,etc.,this paper reviews the most applied linear machines including machine topologies,operating principle and features.In addition,the influence of end effects and the corresponding reduction methods are also summarized.Finally,several commercial applications are exemplified.展开更多
文摘In order to improve the thrust-power ratio index of the linear induction motor(LIM), a novel adaptive genetic algorithm (NAGA) is proposed for the design optimization of the LIM. A good-point set theory that helps to produce a uniform initial population is used to enhance the optimization efficiency of the genetic algorithm. The crossover and mutation probabilities are improved by using the function of sigmoid and they can be adjusted nonlinearly between average fitness and maximal fitness with individual fitness. Based on the analyses of different structures between the LIM and the rotary induction motor (RIM) and referring to the analysis method of the RIM, the steady-state characteristics of the LIM that considers the end effects of the LIM is calculated and the optimal design model of the thrust-power ratio index is also presented. Through the comparison between the optimal scheme and the old scheme, the thrust-power ratio index of the LIM is obviously increased and the validity of the NAGA is proved.
基金This work is supported by National Natural Science Foundation of China(NSFC51777190,NSFC51477150),China.
文摘Linear machines(LMs)produce linear motion without any intermediate transmission mechanisms,thus the whole electromechanical system has simple structure and its efficiency is high.Because of such merits,linear machines have been studied for a long time and rapidly developed in recent years.Due to the characteristic of open structure,linear machines have more diversity than rotary machines in terms of machine topologies.Accounting for the wide applications of linear machines,e.g.Maglev train,precision machine tools,semiconductor processing device,automatic equipment,logistic transport line,ropeless lifter,compressor,etc.,this paper reviews the most applied linear machines including machine topologies,operating principle and features.In addition,the influence of end effects and the corresponding reduction methods are also summarized.Finally,several commercial applications are exemplified.