A Coordinated Reclosing Strategy for Maintained Transformer in Offshore Wind Power Systems

Abstract

Offshore wind power generation system needs to consider the maintained transformers to reclose. The close loop operation can meet the requirement for reclosing the maintained transformer and maximize the use of wind resources without disconnecting wind turbines. However, close loop operation will cause system damping which can easily cause system instability and protection maloperations. To suppress close loop current damping, a flexible reclosing strategy is proposed that coordinates control of the main bus switch and transformer-connected flexible switch which consists of a damping buffer branch and pass branch. The coordinated control of switches realizes the optimized reclosing state of the maintained transformer. Finally, case studies are established in PLECS simulation software to evaluate the effectiveness of the proposed flexible reclosing strategy to eliminate the reclose damping oscillation for maintained transformers in offshore wind power generation systems.