Advanced Topology Design Framework for DC Offshore Wind Farm Collection System

With further exploitation of the resource-abundant deep-sea large wind farms, there has been a growing focus on the development of all-DC grid integrated wind farms. As an indispensable part of the all-DC system, the DC collection system is widely discussed for improved efficiency and cost-effectiveness. However, existing discussions primarily concentrate on the series-parallel interconnection of wind turbines within the collection system, neglecting further exploration into the system’s overall structure. To address this research gap, a novel advanced topology design framework is proposed based on a three-level cascading approach and a multi-objective PSO algorithm. In this proposed framework, the DC collection system is generally designed to incorporate wind turbines connected across three levels, allowing for a combination of series and parallel interconnections. The specific number of turbines and interconnection scheme in each level can be customized for a given wind farm configuration using the optimization algorithm. Experimental results obtained from a typical wind farm demonstrate the proposed framework improves the efficiency and cost-effectiveness of the collection system compared to both series-parallel DC collection system and AC collection system.