Optimal Cabling of Deep-Sea Far-Shore Wind Farm Considering Complex Seabed and Restricted Zones

Offshore wind energy development is currently moving to deep-sea far-shore areas, bringing challenges for its electrical system design. This article proposes an optimization method for the offshore wind farm (OWF) cable routing problem based on a three-dimensional (3-D) spatial representation of wind turbines (WTs), offshore substations (OSs), and the onshore point of common coupling (PCC), bathymetry and restricted zones. Firstly, the complex seabed models for laying the collection and transmission cables of the deep-sea far-shore OWFs are established with restricted zones being taken into consideration. Secondly, the optimization models for the collection system planning are formulated as a minimum spanning tree (MST) problem and a capacitated vehicle routing problem (CVRP) for the star, radial, and ring structures, respectively. Also, the algorithms for WTs clustering and partition, cable crossing avoidance, and optimal cable routing are provided. Finally, the optimization model for the transmission system with a radial structure is established and the rapidly exploring random tree* (RRT*) algorithm is applied for avoiding obstacles in the planning area. The simulation results validate the superiority of the proposed method compared with the traditional two-dimensional (2-D) planar method.