Partial Discharge free Bushing for Thermal Cycling Tests up to 150°C at 10 kV

Lifetime of electrical power apparatus depends on several factors. One important factor is the condition of the insulation system which can be reduced by voids and other defects. Inside these voids discharges may occur which are called partial discharges (PD). Some aspects as voltage level and operating temperature influence the occurrence of PD. Due to higher temperature a higher stress of the insulation system can be expected. Temperature dependent permittivity also leads to reduced PD inception voltages. Thermal cycling leads to further challenges. Alternating temperatures and different thermal expansion coefficients combined with a heat gradient can create cracks inside the insulation. Inside these cracks PD can occur. For PD analysis of samples the measurement setup has to be PD free…