Research on power fluctuation strategy of hybrid energy storage to suppress wind-photovoltaic hybrid power system

Abstract

In this paper, an adaptive hybrid energy storage power optimal allocation strategy is proposed. The strategy aims to suppress the fluctuation of grid-connected power under different operation conditions and improve the operation reliability of a high proportion of renewable energy connected to the grid. Firstly, an online control strategy of grid-connected power fluctuation rate based on model predictive control (MPC) is established. This strategy can realize the grid-connected target power dynamic generation of wind-photovoltaic-energy storage (Wind-PV-ES) hybrid power system and the optimal allocation of energy storage (ES) output power. Secondly, an adaptive hybrid ES power allocation strategy based on the variational mode decomposition (VMD), Hilbert-Huang transform (HHT) and filtering algorithm is constructed to realize adaptive adjustment and optimal allocation of hybrid ES output power. Finally, the hybrid ES capacity configuration is verified by simulation analysis and theoretical calculation. The simulation results show that the proposed hybrid ES output power optimal allocation strategy has certain engineering practical value to suppress the grid-connected power fluctuation.

Keywords

• Grid-connected power
• Hybrid energy storage
• Suppress power fluctuation
• Wind-photovoltaic hybrid generation