Breakdown process experiments of cap‐and‐pin insulators and their EMT leader progression model implementation

Here, breakdown tests of cap‐and‐pin glass insulators with arcing horns, conducted at two different HV labs, are presented. Since only volt–time curves are measured, a curve‐fitting approach to determine leader progression model parameters is taken, which involves modelling of the impulse generator in detail and inclusion of the Motoyama model to simulate the breakdown. Furthermore, a comparison of the breakdown simulation results with LPM parameters for a pure air gap and the measurements is accomplished. Finally, a curve‐fitting procedure is developed to fit the resulting volt–time curves from simulations to the measurements.