Investigation of the partial discharge inception voltage of semiconductor sensor packages at repetitive impulse stress under the variation of pulse steepness and temperature

In this paper a test and measuring system for partial discharge under impulse stress is described. Therefore a low noise impulse source with variable frequency and impulse steepness was designed. The base is a push-pull switch. The measurement was executed according to standard IEC 61934. For the present study, the measuring of the PD signals was performed with high-frequency current transformers (HFCT). The entire test set-up was optimized in several steps. The investigated components are magnetic field sensors, realized in semiconductor plastic packages. The application specific integrated circuit (ASIC) on the low voltage side is galvanically separated from a portion of the Cu leadframe, which is connected to the high voltage application circuit. Subsequently this requires a package intrinsic solid state insulation system which is reliably over the entire lifetime. The PD inception voltages of the sensor ICs were investigated in dependence of temperature and impulse steepness. The results show a clear dependency on the two parameters.