【作者】 赵丽君；

【导师】 崔皆凡；

【作者基本信息】 沈阳工业大学 ， 电力电子与电力传动， 2006， 硕士

【摘要】 本课题针对直线电机特有的端部效应对推力控制系统性能的影响,在合理选择小波函数和进行小波算法研究基础上,提出基于小波理论的改善直线电机推力控制系统性能的方法。同时,磁链的观测精度影响直线电机直接推力控制系统性能,特别是低速时的性能,本文采用小波算法提高磁链观测精度,以达到改善直接推力控制系统性能的目的。 直线电机是一种将电能直接转换成直线运动,而不需要通过任何中间转换机构的新颖电机,具有广阔的应用和发展前景。但是,端部效应是直线电机结构上特有的一种现象,也是使直线电机控制性能下降的主要原因,它的直接表现是电磁推力的周期性非平稳波动。因此,削弱端部效应对直线电机推力性能的影响,为直线电机广泛应用提供理论前提。而在直接推力控制系统中,磁链的观测精度直接影响电机输出推力的平稳性,因此,提高磁链观测精度有利于改善直线电机控制系统稳定运行的性能。 小波分析(Wavelet Analysis)是一门新兴的数学理论和方法,它被认为是傅里叶分析方法的突破性进展。小波分析具有许多特性:良好时频局部化特性、以及多分辨分析的功能,特别适合非平稳信号的处理。因此,本文将小波分析用于直线电机驱动控制系统中,利用小波分析多分辨分析的方法,对端部效应的影响进行研究,并提出补偿方案以达到改善直线电机特有的端部效应对推力控制系统性能影响的目的。其次,将小波分析应用于直线电机直接推力控制系统中,提高绕组电阻辨识精度以及磁链观测精度,进而改善直接推力控制系统中低速性能不理想的问题。最后,通过仿真验证系统性能的改善效果和所提出方法的可行性。更多还原

【Abstract】 Linear motor has a special phenomenon that is end effect. It is influence control system performance of linear motor. In this thesis presents an improvement method of direct thrust control system performance, which based on study and analysis of choice function and algorithm of Wavelet analysis. Observation accuracy of flux linkage influences the performances of direct thrust control system, specially the low speed performance. Wavelet algorithm is used to increase observation accuracy of flux linkage, and the purpose of system improvement has reached.Linear motor is a novel motor, because it can make electric energy transferred into linear motion, which doesn’t need any intermediate conversion, and then it has widely application and development areas. But linear motor structure has a specific phenomenon that is end effect, which is one of major factor influence the linear motor control system performance. Its direct appearance is periodic and non-stable fluctuation of thrust. Therefore, it is offered a theory premise for the linear motor widely application that weakening the influence of the end effect. In direct thrust control system, flux linkage observation accuracy influences the thrust of linear motor. Therefore, it is offered a theory premises that increase the observation accuracy of flux linkage.Wavelet analysis is a novel mathematical theory and method proposed in 1980s. It is as regarded as a breakthrough of Fourier analysis because it has many wonderful characteristics. It is benefit for processing the non-stable signal, because wavelet theory has the characteristic of the time frequency location characteristic and multi-resolution analysis. Therefore, Wavelet analysis is used in direct thrust control system of linear motor in this thesis. End effect influence analysis is based on multi-resolution analysis of Wavelet analysis, and a compensation method for performance influence of linear motor thrust has presented. Second, Wavelet analysis isused in primary resistance identification of direct thrust control system. The observation of flux linkage is improved by accurate identification of primary resistance, and direct thrust control performance at low speeds is further improved. Finally, the feasibility of method and improvement of system performance has been proved by simulation.更多还原