A framework for decentralized design of system controllers using an extended Relative Gain approach

A theoretical framework to design decentralized power system controllers based on a generalized Relative Gain Array (RGA) concept is suggested. The proposed approach constitutes a natural extension to conventional RGA-based structures and may be used to place controllers as well as to supplement information on the phase or sense of loop interaction. This approach also allows better coordination of control capabilities. Techniques to choose the best input-output pairs that incorporate phase information associated with the control structure are introduced and extensions to the standard RGA-based techniques are proposed. A case study with a 16-machine, 68-bus test system shows that the method is effective and results in improved control performance.