A study on wide-area controller design for inter-area oscillation damping

In a modern power system, damping of an inter-area mode is crucial as it limits the power transfer capability. With the progress in Wide-Area Measurement System (WAMS), now dynamic data from wide geographical areas are available readily. The accuracy of such data motivates to be used as feedback for controllers, which can have better performance. The placement of such controllers and the signals to be considered as feedback with the redundancy, such that action will be effective is an interesting idea to deal. The paper deals with the issue of wide-area loop selection in a detailed manner. The selection considers not only being strongly controllable/observable but also the interaction and robustness issue. A static controller performance is compared with dynamic controllers (Lead-Lag compensator, PI Controller, Multi-Objective Controller). The controllers are synthesized so as to minimize the H∞ norm. The designed controllers are validated through a four machine case study.