An adaptive wide-area damping controller based on generalized predictive control and model identification

Abstract

The wide-area damping controller (WADC), using remote signals obtained from a wide-area measurement system (WAMS) as the input, has been employed to enhance the stability of the large-scale inter-connected power system. The time delay caused by transmission of remote signals is one of the key factors influencing the whole system stability and damping performance. This paper presents an adaptive WADC based on generalized predictive control and model identification. The proposed WADC is implemented by adding its output signal to the excitation system of a selected generator. A recursive least-squares algorithm (RLSA) with a varying forgetting factor is used to identify the model of power system. Based on this model, the generalized predictive control considering control output constraints is employed. Simulations studies undertaken on a two-area four-machine power system show that the proposed adaptive WADC not only can damp the inter-area mode oscillations effectively under varying operation conditions and different disturbances, but also has better robustness against to the time delay existing in the remote signals. The comparison studies with the conventional WADC are also provided.