Transient Behavior Analysis of Offshore Wind Turbines During Lightning Strike to Multi-Blade

Abstract

A set of analytic formulas are presented to evaluate the circuit parameters of blade, tower, three-phase cable, and monopile foundation. On the basis of the circuit parameters, the circuit model is built and a transient analysis is carried out for the offshore wind turbine (WT) under lightning strikes to multi-blade. The lightning transient responses can be obtained at the different locations of the offshore WT by using the circuit model. An experimental measurement with a reduced-scale WT has been made for checking the validity of the circuit parameter formulas and circuit model. The measured results are compared with the calculated ones and a good agreement is shown between them. The practical feasibility of the circuit model is also examined by a numerical example of an actual Chinese-built offshore WT.