Secondary Frequency Regulation Control of Energy Storage Using the Reserve Capacity of Synchronous Generator

In this paper, a control strategy for energy storage (ES) participating in secondary frequency regulation (SFR) is proposed, which is based on the comprehensive consideration of ES and synchronous generator (SG), and fully utilizes the reserve capacity of SG. Firstly, the power limitation and variation trend of ES units during both stages of SFR and state of charge (SoC) recovery are quantitatively analysed. Then, the different intervals of area control error (ACE) signal are used to describe the reserve capacity of SG for SFR, which is used to modify the reference power of ES during SFR. Since the power limit of SG and requirements of SoC recovery are taken into consideration, the proposed strategy can contribute to the cooperation of both SG and ES units, and fully exploit the advantages of the equipment. Finally, the MATLAB/SIMULINK based simulation has been carried out, and results shows that the comprehensive control strategy has advantages in improving the effect of frequency regulation and maintaining SoC within normal range.