Wide-area power system stabiliser based on model-free adaptive control

Abstract

The interconnection of regional power grids has resulted in inter-area low-frequency oscillation, which has become a serious problem that threatens the security of power systems. Wide-area power system stabiliser (WAPSS) is an effective device to damp this oscillation. Given that the interconnected multi-machine power system is a strongly non-linear and complex system with time-varying structure and operating conditions, satisfactory control performance of WAPSS is difficult to obtain by using conventional model-based control methods. In this study, a data-driven control method called model-free adaptive control (MFAC) is introduced to WAPSS design. The MFAC algorithm is improved to meet the wide-area damping control requirements in consideration of system disturbances. The stability of the closed-loop system with the improved MFAC-WAPSS is also analysed, and the parameter settings of the improved MFAC algorithm are provided in detail. The improved MFAC-WAPSS can adjust its parameters adaptively only based on the input and output data and avoid the complex system modelling process. The proposed adaptive WAPSS is evaluated on a simplified New England power system. Simulation results show the effectiveness of this new technique.