Two-layer Emergency Frequency Control Scheme for Sending-end Power Grid With Multi-energy Storage Systems

Abstract

With the increase of the proportion of the renewables, the system inertia and frequency regulation capability in the sending-end power grid have become seriously insufficient, making the frequency stability issue increasingly prominent. This paper proposes a two-layer emergency frequency control scheme for sending-end power grid with multi-energy storage systems (MESSs) to enhance the frequency stability. At the upper layer, the total power control commands of MESSs are optimized to minimize the control energy consumption, considering the constraints of frequency and control power. It achieves the optimal utilization of energy. At the lower layer, the power commands of each ESS are solved by the model predictive controller (MPC), with the objective of minimizing the loss cost and sate of charge (SOC) deviation of ESS, considering the operating characteristics of different ESS. It achieves the reasonable distribution of power. Finally, the effectiveness of the proposed control scheme are verified in IEEE-39 bus system. The results show that the proposed scheme can effectively enhance the system frequency stability for the sending-end system.