TY - EJOU AU - Wang, Weiru AU - Cao, Yulong AU - Wang, Yanxu AU - You, Jiale AU - Zhang, Guangnan AU - Xiao, Yu TI - Combined Wind-Storage Frequency Modulation Control Strategy Based on Fuzzy Prediction and Dynamic Control T2 - Energy Engineering PY - 2024 VL - 121 IS - 12 SN - 1546-0118 AB - To ensure frequency stability in power systems with high wind penetration, the doubly-fed induction generator (DFIG) is often used with the frequency fast response control (FFRC) to participate in frequency response. However, a certain output power suppression amount (OPSA) is generated during frequency support, resulting in the frequency modulation (FM) capability of DFIG not being fully utilised, and the system’s unbalanced power will be increased during speed recovery, resulting in a second frequency drop (SFD) in the system. Firstly, the frequency response characteristics of the power system with DFIG containing FFRC are analysed. Then, based on the analysis of the generation mechanism of OPSA and SFD, a combined wind-storage FM control strategy is proposed to improve the system’s frequency response characteristics. This strategy reduces the effect of OPSA and improves the FM capability of DFIG by designing the fuzzy logic of the coefficients of FFRC according to the system frequency index in the frequency support stage. During the speed recovery stage, the energy storage (ES) active power reference value is calculated according to the change of DFIG rotor speed, and the ES output power is dynamically adjusted to reduce the SFD. Finally, taking the IEEE 39-bus test system as an example, real-time digital simulation verification was conducted based on the RTLAB OP5707 simulation platform. The simulation results show that the proposed method can improve the FM capability of DFIG, reduce the SFD under the premise of guaranteeing the rapid rotor speed recovery, and avoid the overshooting phenomenon so that the system frequency can be quickly restored to a stable state. KW - Doubly-fed induction generator; frequency fast response control; output power suppression amount; frequency response characteristics; second frequency drop; combined wind-storage DO - 10.32604/ee.2024.055398