Delay-Independent Wide-Area Damping Control Using Scattering Transformation

Abstract

Utilization of a communication network to transmit remote-control signals might introduce time delay into the control loop, which degrades the controller efficacy. This paper proposes a new design of wide-area damping controller based on scattering transformation to enhance power system stability. The proposed control approach is comprised of a classical structure in addition to two scattering transformation ports. These ports are inserted between the power system and the wide-area damping controller (WADC) to regulate the signal exchanging between them. Since the WADC is a centralized controller, the time-delay imperfections are considered in the design stage. The proposed controller improves the system damping performance thanks to the achieved time-delay compensation. The effectiveness of the proposed controller is demonstrated by implementing the controller in several case studies under different disturbance scenarios. The proposed controller performance is benchmarked with the classical WADC based on lead-lag structure. The efficacy of the proposed controller is confirmed to reduce the time delay resulting in a better power system stability.