Robust FACTS control design using the H∞ loop-shaping method

The design of a robust control for the second generation of FACTS devices such as STATCOM, SPFC and UPFC using a H_∞ loop-shaping design via a normalised coprime factorisation approach, where ´loop-shape´ refers to the magnitude of the loop transfer function L=GK as a function of frequency is presented. Since this method is based on classical loop-shaping ideas, it is relatively easy to implement. Furthermore, comparing it with the other methods of H_∞ robust control, it is more flexible and is not limited in its applications. Simulation of the system following a disturbance is performed to demonstrate the effectiveness of the proposed controller