Frequency Control of a Wind-Diesel System Based on Hybrid Energy Storage

To improve the stability of a wind-diesel hybrid microgrid, a frequency control strategy is designed by using the hybrid energy storage system and the adjustable diesel generator with load frequency control (LFC). The objective of frequency control is to quickly respond to the disturbed system to reduce system frequency deviation and restore stability. By evaluating the area control error, the disturbance state of the system can be divided into four different areas by a corresponding control strategy for precise adjustments. For the diesel generator, an adaptive sliding mode (SM) algorithm is used to design LFC that can participate in frequency modulation. The frequency coordination control strategy proposed in this paper can realize the partition adjustment according to different resources, and ensure frequency stability. The proposed control strategy is verified by RTDS simulations in multiple scenarios.