A modified static voltage control algorithm based on optimal multiplier method and dynamic generation characteristics

With the fast development of wide area measurements, communication techniques and dynamic security assessment (DSA) tools in power systems, dynamics based stability control strategies are attracting more and more research attentions as an effect way to handle complicated control objectives and improve control accuracy. However, due to its heavily relying on the time domain simulation, the computation burden of these dynamic based methods has also been greatly increased. On the other hand, static methods, which have been developed for years based on simplifications of the dynamic systems, are constantly appreciated by industries for their maturity, fast computation time and practical for online applications. In this paper, in order to improve the accuracy of static voltage stability control algorithms, the rules of simplifying a generator reactive power limitation, which is one of the most important contributing factors for voltage collapses, has been reviewed. A refined static model is proposed based on considering this limitation characteristics in a dynamic control framework. The static voltage stability control is computed by iteratively applying an optimal multiplier method. It shows that this method only add a small amount of computation burden compared to the original static method, while it can improve the control performance significantly during a dynamic process. An example voltage collapse is discussed to illustrate the algorithm and provide comparisons.