Optimization of transient stability control - Part-I: For cases with the same unstable mode

Abstract

Based on the stability margin provided by the EEAC, the unstable contingencies can be classified into sets according to their unstable modes. This two-part paper develops a globally optimal algorithm for transient stability control to coordinate preventive actions and emergency actions. In the first part, an algorithm is proposed for a set of contingencies with the same unstable mode. Instead of iterations between discrete emergency actions and continuous preventive actions, the algorithm straightforwardly searches for the globally optimal solution. The procedure includes assessing a set of insufficient emergency schemes identified by the EEAC; calculating the related preventive actions needed for stabilizing the system; selecting the scheme with the minimum global costs. Simulations on a Chinese power system highlight its excellent performance. The good results are explained by analogizing settlements for 0-1 knapsack problems using multi-points greedy algorithm.