Adaptive Real-Coded Genetic Algorithm for Identifying Motor Systems

In this paper, the main objective is to identify the parameters of motors, which includes a brushless direct current (BLDC) motor and an induction motor. The motor systems are dynamically formulated by the mechanical and electrical equations. The real-coded genetic algorithm (RGA) is adopted to identify all parameters of motors, and the standard genetic algorithm (SRGA) and various adaptive genetic algorithm (ARGAs) are compared in the rotational angular speeds and fitness values, which are the inverse of square differences of angular speeds. From numerical simulations and experimental results, it is found that the SRGA and ARGA are feasible, the ARGA can effectively solve the problems with slow convergent speed and premature phenomenon, and is more accurate in identifying system’s parameters than the SRGA. From the comparisons of the ARGAs in identifying parameters of motors, the best ARGA method is obtained and could be applied to any other mechatronic systems.

基于两级模糊控制器的独立负载液压系统的压力流量复合控制特性研究（英文）

目的:常规负载口独立控制研究多采用商业阀进行,因其阀芯位移控制器为封闭式结构,所以阀芯位移的动态特性难以调整,进而影响了系统的压力和流量控制性能。本文旨在探讨负载口独立控制系统中阀芯位移特性对系统压力和流量控制的影响,并研究提高系统压力和流量控制性能的方法。创新点:1.设计基于两级模糊比例积分微分(PID)的压力和流量控制器;2.设计基于阀芯位移反馈的流量控制器;3.建立试验模型,成功实现液压系统高动态压力流量复合控制。方法:1.通过理论分析得到影响系统压力和流量的关键因素(公式(9)和(13));2.提出位移控制为内环、压力和流量控制为外环的两级模糊PID控制算法,并开发相应的控制系统(图2～4);3.通过仿真和实验分析,验证本文提出的控制器所具有的阀芯位移、系统压力和流量的控制效果(图13～18)。结论:1.两级模糊PID控制器具有较好的系统压力和流量控制效果;2.基于阀芯位移反馈的流量控制器具有较高的流量控制精度;3.运用本文设计的可编程控制系统进行液压系统的压力流量复合控制,稳定时间小于200 ms,使系统动态特性得到提高。