Preventive primary frequency response control of energy storage systems for a high renewable penetrated power grid

Low inertia in power grids with high renewable penetration may lead to severe frequency concerns after disturbances. Meanwhile, fluctuations of renewable generation can make the frequency deviation even worse, due to their large proportion in total generation capacity. Energy storage system (ESS) is a promising solution to relief the frequency issues, taking advantages of its fast response and relatively low cost compared with hydro or thermal generations with similar frequency support capability. However, ESS commonly responses to frequency deviation following a droop control with preset droop rate and deadband width, such constant primary frequency response parameter (PFRP) setting is insufficient for a system with various renewable fluctuation patterns and possible contingencies. In order to overcome this issue, this work proposes a preventive control scheme to determine PFRP of ESS, which is able to dynamically adjust droop rate and deadband width along with day-ahead dispatch using a multi-period scenario-based optimal power flow (OPF) formulation. The effectiveness of the proposed approach is verified using the test cases from a real-world province-level power grid with high renewable penetration in China. Numerical results show that the proposed approach is able to achieve required post-disturbance frequency performance by only increasing less than 3% operating cost.