Wind-storage coordinated control strategy for inertia enhancement of high ratio renewable energy power systems

The replacement of thermal power units with renewable energy power generation equipment like wind and photovoltaics has decreased the inertia level of power systems and weakened the frequency stability of the power grid. In order to improve the inertia level of the new power systems and strengthen the inertia support capability of the renewable energy power system to the grid, a wind-storage coordinated control strategy for the inertia enhancement of high-proportion renewable energy power system is proposed in this paper. A time domain model of the inertia response of the wind-storage coordinated control system is also established. An inertia level enhancement strategy of virtual inertia and virtual sag coordinated control of wind-storage joint system is proposed. It improves the system inertia using the analysis results of system inertia requirements as data support and considering the characteristics of battery storage with fast charging and discharging response, and flexible capacity configuration. In addition, the effectiveness of energy storage system (ESS) participation in system inertia enhancement is guaranteed by proposing energy storage based on the ESS state of charge (SOC), which participates in the inertia of the new energy power system to enhance the control coefficient adaptive strategy. Finally, a comparative analysis is carried out using RTLAB simulation test to verify the effectiveness of the method proposed in this paper.