DC Collection System Layout Optimization for Offshore Wind Farm

DC collection system for an offshore wind farm has become an alternative to AC system. Since the DC system requires high-cost converter technology to be integrated to existing AC grid, the cost of overall system becomes a concern. Submarine XLPE collection cable connecting wind turbines with substation is part of the electrical system cost. Effective cable layout design and right cable size selection can contribute to cost reduction. This paper presents a DC collection system layout optimization for offshore wind farm using Genetic Algorithm and Traveling Salesman Problem. The cable cost is minimized as an objective function considering cable power losses, cable cross-section, and cable length. Case studies are conducted considering fix substation locations and optimum number of feeders are identified. Results are compared with optimized AC layout in an earlier study and show that DC collection system cable cost has superiority over AC system cost.