An Economic study of Power Secondary Frequency Regulation with Different Energy Storage Systems

In recent years, the power grid structure has undergone great changes, and the penetration of renewable generations challenges the reliable and stable operations of the power grid. As a flexible resource, energy storage systems can be applied to the field of secondary frequency regulations which support conventional thermal units and improves the stable operations. In this paper, an optimal operation strategy of energy storage systems in a regional power grid is presented, and the economic feasibility of different types of energy storage system participating secondary frequency regulation market is studied. Firstly, the mathematical modeling and analysis of the power system frequency regulation with energy storage systems and conventional thermal power units in a regional grid is carried out. Then, a comprehensive economic feasibility study of different energy storage systems participating secondary frequency regulation market is performed. Finally, a comprehensive performance analysis of the secondary frequency regulation is performed according to the system auxiliary service policies and frequency regulation performance indices. The case study results verify that the energy storage systems can greatly improve the secondary frequency regulation performance. However, from the investment point of view, certain economic compensations are required to ensure the economic feasibility of the energy storage systems operations.