基于静态H_∞回路成形法的多通道低阶鲁棒阻尼控制器设计  

Design of multi-channel low order robust damping controller based on static H_∞ loop-shaping method

作　　者：李志晗 张英敏[1] 张爽 曾雪洋 李兴源[1] 

机构地区：[1]四川大学电气信息学院,四川成都610065 [2]国网宁夏电力公司电力科学研究院,宁夏银川750011

出　　处：《电力系统保护与控制》2018年第1期23-29,共7页Power System Protection and Control

基　　金：国家电网公司科技项目(SGNXDK00BGJS160021)~~

摘　　要：针对鲁棒控制方法设计高压直流附加阻尼控制器时普遍存在的控制器阶数过高的问题,提出一种静态H_∞回路成形设计方法同时抑制次同步和低频振荡,所设计的控制器具有和权函数相同的阶数。采用总体最小二乘旋转不变技术分析了交直流互联系统中次同步和低频振荡共存的现象,并辨识出相关振荡频率和系统降阶模型。利用巴特沃兹滤波器将不同的振荡模态分解到不同的通道,根据静态H_∞回路成形法对每个振荡模态设计附加阻尼控制器,降低了控制器间相互影响。在PSCAD/EMTDC中对向上直流孤岛运行下的模型进行仿真验证。仿真结果表明,基于静态H_∞回路成形法设计的控制器对系统振荡具有较好的控制效果和较强的鲁棒性。同时所设计的控制器阶数较低,采用输出反馈,便于工程实践。For the common problem of the controller order is too high when using the robust control method to design damping controller for HVDC transmission system. A method based on static H∞ loop shaping is proposed to suppress the sub-synchronous oscillation and low frequency oscillation. The designed controller has the same order as the weight function. The order-reduced model and the sub-synchronous oscillation and low frequency oscillation modals in AC-DC system are obtained by total least squares-estimation on signal parameters via rotational invariance techniques. Then, the different oscillation frequencies are decomposed into different channels by Butterworth band-pass filters. The additional robust damping controller is designed based on static H∞ loop shaping, restraining the interaction between control channels. Xiangjiaba-Shanghai DC link under island operation condition is simulated using electromagnetic transient program PSCAD/EMTDC to demonstrate the proposed control strategy. Simulation results in PSCAD/EMTDC show that the designed multi-channel damping controller can well suppress different oscillation modes of the system and possesses good robustness. Besides, the order of the controller is low and it adopts output feedback control, which are convenient for practical application.

关 键 词：次同步振荡 低频振荡 带通滤波器 鲁棒性 静态H∞回路成形 低阶控制器 

分 类 号：TM712[电气工程—电力系统及自动化]