Multi-time scale adequacy evaluation of the power system with high penetration of renewable energy sources based on empirical mode decomposition

Adequacy, especially in the power system with high penetration of renewable energy sources, is a crucial consideration in power system planning and operational dispatching. A multi-time scale adequacy evaluation method based on empirical mode decomposition (EMD) is proposed, taking into account the multi-time scale characteristics of renewable energy sources and the response characteristics of flexible regulation resources. In this method, a net load curve is decomposed into several component curves by the EMD algorithm. Then, the adequacy demand on each time scale is obtained by waveform recognition. Furthermore, the available adequacy resources on different time scales are quantified according to the regulation models of flexible resources. By analysing the adequacy demand and available adequacy resources of the power system on the same time scale, the adequacy evaluation indices on each time scale can be calculated and weighted to form the comprehensive indices. Finally, the adequacy evaluation indices on each time scale with different capacities of renewable energy sources and energy storage systems are compared and analysed using a practical power system as a case. Simulation results show the validity of the multi-time scale adequacy evaluation method.