Single cable layout boundary of offshore wind turbines considering terminal voltage distribution

With the expansion of offshore wind farms(OWF), attention has been paid to the voltage stability of wind turbines (WT) in the scenario of island operation mode. The excessive terminal voltage of few WTs caused by the terminal voltage distribution will reduce their power generation efficiency or potentially lead to trip-off. A calculation methodology of OWFs' single cable layout boundary is proposed in this paper to optimize the number of WTs connected to a single cable. The single cable layout boundary can be used to improve the WTs' terminal voltage stability and avoid the degradation of power generation efficiency. First, the terminal voltage function is constructed based on the power flow of the π-type cable, and the terminal voltage distribution law within WTs connected to the single cable is revealed. Second, in several grid-connection voltage scenarios, the terminal voltage boundaries are calculated to restrict the number of WTs connected to the single cable. Case studies built in MATLAB are carried out for performance verification of the proposed terminal voltage boundaries. OWFs' single cable layout boundary can effectively evaluate the terminal voltage stability of WTs in current OWFs and guide the layout planning of upcoming wind farms.