基于在线辨识和区域极点配置法的电力系统低频振荡协调阻尼控制

Coordinated Damping Control of Power Systems Low-Frequency Oscillation Based on On-Line Identification and Region Poles Assignment

基于均匀阻尼思想和低频振荡的在线辨识,提出采用区域极点配置法设计阻尼控制器,以实现大系统低频振荡的协调阻尼控制。首先分析了电力系统低频振荡的阻尼特性和机组参与振荡的特点,提出实现均匀阻尼控制的条件和方法;然后基于低频振荡特征的辨识进行阻尼评估,确定均匀阻尼控制的目标;针对辨识模型进行降阶,得到适合控制器设计的降阶模型,最后采用区域极点配置法求出控制器的参数,同时抑制发电机参与的多个振荡模式。由于辨识的模型中考虑了其他发电机和调节系统对本机的影响,极点配置的目标保证发电机所参与振荡模式的阻尼尽量均匀,避免了其他模式阻尼的过度削弱,因此低频振荡控制具有一定的协调性,同时控制器的反馈信号为本地信号,实现了系统的分散协调控制。以新英格兰10机39节点系统为例,说明了本文设计控制器的有效性和鲁棒性,为电力系统低频振荡的分散协调控制提供了新思路。

Based on the uniform damping thought and the identification of the low-frequency oscillation （LFO）, the paper puts forward the design method of damping controllers which makes use of region pole assignment method to realize coordination damping control of LFO. First, the damping characteristics of power systems oscillation and the characteristics that machines are involved in oscillations are analyzed, and the condition and method of realizing uniform damping control are put forward. Then evaluating the damping based on the oscillation characteristics identification, the control object of uniform damping is determined. And reduced order models used to design controllers are deduced by the order reduction of identification models. Finally controllers＇ parameters are calculated by poles assignment method which damp several oscillation modes that generator participated in. Because identified models consider fluencies of other machines and the control goal avoids decreasing damping of other modes in excess, the coordination of controllers is realized. At the same time, the feedback signal of controller is local and the decentralized coordinated control is realized. At last, take New England 10-machine 39-node system as example, the simulation proves controllers designed validity and robust, the method put forward a new thought for restraining LFO.