Stability Analysis of Hybrid GFM Offshore Wind Turbines and GFL Floating Photovoltaic Connected with DR-HVDC System

Offshore floating photovoltaic (FPV) represents an effective solution for the future development of renewable energy generation. However, its development scale is strictly limited by the high construction costs. Consequently, this paper proposes a scheme for a hybrid offshore renewable power plant including grid-forming (GFM) wind turbines (WTs) and grid-following (GFL) FPV integrated with a diode rectifier based HVDC (DR-HVDC) system. Firstly, impedance models are established for the different sections of the system. Next, employing the impedance approaches, the effect of the controller parameters on the small-signal stability of the system is investigated. The results indicate that a smaller GFL FPV current loop bandwidth deteriorates stability, whereas the phase-locked loop (PLL) of the GFL FPV has little effect on the stability.