This paper investigates a hybrid energy storage system (HESS) consisting of a vanadium redox flow battery (VRFB) and a supercapacitor (SC), integrated into a large offshore wind farm (OWF) and a parallel offshore platform (OP). The power of the OP is efficiently and stably transmitted to a land-based multi-machine power system (MMPS) with two-area four synchronous generators (SGs) through a high-voltage direct current (HVDC) link based on a modular multi-level converter (MMC). To further enhance the system’s stability and response performance, this paper employs modal control theory to design a proportional-integral-derivative (PID) supplementary damping controller (SDC) for the MMC. The grey wolf optimization (GWO) algorithm is employed to update the three key parameters of the PID SDC by optimizing its performance. In the small-signal stability analysis and dynamic analysis, different cases are compared. For dynamic studies, simulations are conducted by incorporating actual offshore wind speed variations to compare the system’s stability under various scenarios.
Wang et al. (Mon,) studied this question.