Particle-Initiated Breakdowns in Compressed Gas Insulation Under Time-Varying Voltages

The need is growing for an analytical model to describe the performance of particle-contaminated compressed gas insulation. The model should take into account the wide practical variety of particle shapes and sizes, insulation configurations, applied voltage magnitudes and wave forms, and gas pressure. This work introduces ´Breakdown Voltage Profile´ as an attempt in that direction. The profile offers a description of the instantaneous breakdown voltage as a function of the location of a given particle within the gaseous insulation. The profile explains and, in turn, predicts such characteristics as critical particle position and free-particle and fixed-particle breakdown voltages. When properly combined with the particle moving trajectory under a transient (impulse) or steady state voltage, the profile enables the determination of the critical voltage magnitudes.