Fault-Tolerant Control of Multiarea Power Systems via a Sliding-Mode Observer Technique

Abstract

This paper is focused on solving the problems of fault estimation and fault-tolerant control for multiarea power systems with sensor failures. First, the estimations of the system states and fault vectors are determined using an improved sliding-mode observer technique. Moreover, a derivative gain and a proportional gain are introduced to design the resultant sliding-mode observer more freely, and a discontinuous input is given to reduce the impact of sensor faults and aggregated uncertainties. Then, based on the obtained state estimates, an integral-type sliding-mode control scheme against faults and disturbances is proposed to ensure that the resultant fault system is asymptotically stable, from which each subsystem states in the multiarea power system can be driven onto the designed sliding-mode surfaces in both the state estimation and error estimation spaces. Finally, a three-area power system is simulated to validate the feasibility of the developed fault-tolerant control scheme.