Breakdown and tracking properties of rubber materials for wind turbine blades

The use of rubber materials in wind turbine blades, for example in controllable trailing edge flaps, requires research on their behavior under heavy exposure to electric fields and electrical discharges. Since the complex construction of blades usually involves several and often inhomogeneous materials, the testing methods selected should reflect the realistic conditions. In this paper the applicability of rubber materials to thunderstorm environments is studied by performing electric breakdown tests and tracking resistance tests on selected samples, and the findings are related to the possible future application of rubber materials to wind turbine blades.