抗IPS频率波动的两种改进重复控制方法

独立电力系统惯性系数小、源载耦合度高,系统频率极易产生较大的波动,因此,接入系统的并联有源滤波器SAPF的电流控制器必须基于电网频率波动而设计。对传统重复控制方法进行改进,提出了2种快速重复控制方法（fast repetitive control,FRC）,通过缩小重复环节延迟时间来提高响应的快速性,其中,自抗频扰FRC从结构的改进获得较宽的谐振频宽,基于内模Q的FRC通过内模系数Q的引入使重复谐振项呈现为准谐振特性。基于幅频特性比较分析了两者的控制性能,讨论其适用范围,并结合零极点分析,进一步讨论2种控制器参数与SAPF系统稳定性之间的关系。仿真与试验结果表明,与传统重复控制方法相比,文中提出的2种快速重复控制方法均体现出动态响应速度高、静态误差小和抗电网频率波动的特点。

HOS AND GA BASED INTERFERENCE REJECTION IN DIRECT SEQUENCE SPREAD SPECTRUM COMMUNICATION SYSTEMS

A new Higher Order Statistics (HOS) and Genetic Algorithm (GA)-based interference rejection filter is introduced. Compared with the adaptive filters based on second-order statistics and gradient algorithm, the HOS and GA-based filter can reject the interference more efficiently, is independent of uncorrelated Gaussian noise, tends to converge to the optimum solution and is much less sensitive to the choice of the step size parameter. Computer simulations show that the method can reject narrowband interference efficiently.