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Within the scope of the present work, analysis of the lightning protection system of wind turbine rotors were made. In the second chapter, a general overview on the phenomena of lightning and their impact on wind turbine will be given. First, different type of lightning are explained with their general characteristics and the physical processes inside a lightning channel. Technical possibilities of describing a leader channel are given. To show the impact of lightning on wind turbines, the general risk of a lightning strike to a turbine will be assessed and possibilities of state-of-the-art lightning protection systems are given. Based on these lightning protetion systems, the general attachment process between wind turbine and lightning is explained. The third chapter concentrates on the interception efficiency of a receptor based lightning protection system for wind turbine blades, taking the attachment process into account (LHK08, LK07, LKK+07, LHK07). At first, the interception probability according to FEM simulations will be given. Then, state-of-the-art attachment tests for blades with one and two receptors are compared. Based on the interception simulations, the laboratory setup is modified to account for a virtual leader position, giving information on the interception efficiency of each receptor. By using UV camera technique, the predischarge mechanisms are observed for the same blade positions as in the simulation. The influence of the electrically insulating glass fiber shell on this process will be pointed out. Simulations of each respective laboratory setup were analysed according to the streamer criterion for a comparison with the laboratory experiments. Chapter four analyses a conductive coating as an alternative or extension to the receptor based lightning protection system (LKHK07). Device under test was the original weather coating with different concentrations of the conductive particles. As experiments, impuls voltage and impulse current experiments were performed. They will give information on the conducting abilities of the coating as well as on its influence on the surface breakdown voltage. For means of comparability with results of the aviation industry, an aluminium mesh was analysed concerning its abilities to function as lightning protection system on wind turbine blades. Laboratory experiments taking the mesh aperture size and the filament thickness into account were conducted. Further, the influence of the matrix material around the mesh was analysed. In chapter five, the electromagnetic load within the wind turbine hub will be analysed as it might accur during a lightning strike. This may help to design and protect the hub-based control systems more effecively against the lightning strikes. An electromagnetic simulation model of a cast iron wind turbine hub under lightning conditions will be derived (LKT+06b). Laboratory experiments were performed to verify the magnetic field distribution inside the hub due to an injected impulse current. With a special cast iron model box nonlinear material properties of the cast iron under high impulse current loads will be analysed. Further, the shielding abilities of the steel-made control boxes inside the hub were subject to investigation with a special emphasis on the shielding improvement abilities.