Simulation on air-gap discharge based on PIC-MCC method

The partial discharge (PD) in a void of solid insulation is a typical kind of PD behaviors. The microscopic process of particle movement is simulated in this paper by combing particle in cell (PIC) method and Monte Carlo collision (MCC) method, which possess great significance for researching air-gap discharge. Adopting PIC to analyze force on particle motion and update electric density in the static aspect. Besides that, we also induce MCC to deal with the changes caused by collisions between electrons and neutral particles, including elastic, excitation and ionization types, which relies on cross sections to decide collision probabilities. Simulation results show detailed motion process and the streamer discharge phenomenon. The PD current pulse waveform possesses the trend of steep rising edge and gentle falling edge comparing with Gaussian distribution. Its characteristics are discussed by adjusting simulation parameters in this paper.