H_∞PSS设计中加权函数的选择及模型降阶

基于H∞鲁棒控制理论的基本原理,设计了电力系统稳定器,克服了传统电力系统稳定器(PSS)鲁棒性差的缺点。针对H∞PSS设计中,权函数的选择较困难,以及H∞PSS阶数往往很高的缺陷,提出了选择权函数时较为通用的方法,以及基于Gram矩阵的均衡降阶方法,并说明了当直接从MATLAB工具箱得到的H∞PSS不是最小实现模型时,如何降阶。为了与传统PSS进行比较,针对单机无穷大系统受到扰动后发生低频振荡的例子,给出了几组仿真试验结果。结果表明H∞PSS能够在较大的运行范围内抑制振荡,显示了良好的鲁棒性。

Selection of weighting function and order reduction in H∞PSS design

Based on H∞ robust control theory, an improved power system stabilizer is designed. In conventional H∞PSS design, it's hard to select weighting function, the controller always has high order and the robust performance is poor. A general weighting function selecting method and a balanced method of reducing the order of the controller based on gram matrix are presented. The procedure to reduce the order of the controller is also presented when the controller isn't a minimal realization model. Simulations results show that H∞PSS restrain oscillation under rather wider range of operating condition than the conventional PSS and better robustness of H∞PSS is obtained.