Cooperative Control Strategy for Offshore Wind Farm Black-start Based on Diesel Generator

With the large-scale utilization of clean energy such as wind energy, the scale of construction of offshore wind farm (OWF) is gradually expanding. When a major blackout occurs in the coastal local power grid, if the black start (BS) capability of OWF is used to start the onshore thermal power unit, the process of power grid restoration can be accelerated. In order to enable OWF to have the BS capability, this paper uses a small-capacity diesel generator as a supporting power source to start offshore wind turbines (OWTs), and uses a step-up transformer and a high-voltage long submarine cable to supply power for the auxiliary machine of the onshore thermal turbine. In order to improve the frequency and voltage regulation capability of the system and make the BS system operate stably when high-voltage submarine cables and auxiliary machines of thermal power units are connected, a wind-diesel coordinated control strategy and wind turbine dynamic reactive power control are proposed, respectively. Grid-side converters (GSCs) of WT are used as reactive power compensator. Finally, the simulation results suggest that the proposed scheme and strategy are rational and feasible.