考虑动态边端效应的六相直线感应电机数学模型及矢量控制

摘要

针对直线电机动态边端效应导致参数时变、推力下降的问题,以短初级双边六相直线感应电机为研究对象,考虑动态边端效应,详细分析初级运动速度、次级漏感对感应涡流变化和等效激磁电感下降的影响规律.通过涡流损耗计算推导次级等效电阻表达式并利用广义Clack变换解耦,建立六相直线感应电机考虑动态边端效应的数学模型.基于该模型提出一种动态边端效应修正系数在线计算的矢量控制策略,该策略通过直接修正滑差频率和转矩电流,能够补偿动态边端效应造成的推力下降,提高系统的控制精度.通过搭建仿真模型和实验平台,验证了所述理论及所采用控制策略的正确性.%Aiming at the problem of time-varying parameters and thrust drop caused by dynamic edge effect of linear motor, the research object is short primary bilateral six phase linear induction motor, considering dynamic end effect. The effect of velocity and secondary leakage inductance on induced eddy current and magnetizing inductance was analyzed in detail. Through the calculation of eddy current losses, the secondary equivalent resistance was derived and the mathematical model of six phase induction linear motor considering the dynamic end effect was established by using the generalized Clack transform. Based on the model, a vector control strategy for on-line calculation of dynamic edge effect correction coefficients was proposed, which achieves compensation for thrust drop caused by the dynamic end effect by correcting the current of q-axis and slip frequency directly. The strategy also improves the control accuracy of the system. The simulation model and the experimental platform were built to verify the correctness of the theory and the control strategy.