Insulation coordination of a wind turbine and a power distribution line

The lightning damage is one of the most serious problems for wind turbine generator systems and distribution/transmission lines. Direct lightning strokes to a wind tower or a blade frequently cause damages in the wind turbine generator systems. Direct lightning strokes to a distribution line have been considered for lightning protection design. The lightning back-flow current is also an important factor for the lightning protection design of a distribution line. Thus, the lightning protection design of a wind turbine generator system must consider lightning overvoltages coming from a distribution line and damage to the distribution line. Insulation coordination should be considered for rational lightning protection design. This paper discusses an insulation coordination design of a wind turbine and a distribution line. Simulations are carried out by the EMTP for such parameters as lightning current and grounding resistance.