Simulation Of Surface Charge Accumulation On High Voltage DC Composite Insulator

Composite insulator has becomes a major carrier of external insulation in thehigh voltage transmission because of its excellent anti pollution flashoverperformance. Surface charge will make the flashover voltage drop, so it’s important toresearch surface charge accumulation mechanism on composite insulator under highvoltage DC and use it to prove the insulation performance. The main work of thispaper is to simulate the gas discharge process in atmospheric environment, in order toget a more profound understanding of the surface charge accumulation mechanism oncomposite insulator. And then provide the necessary theoretical support for the designof composite insulator.In this paper, we established the model of composite insulator according to thesize of FXBW6-10/70. Using finite element software simulate electric fielddistribution of this model in three cases: no surface charge accumulation, surfacenegative charge accumulation and surface positive charge accumulation.The PIC/MCC model is used to simulate the process of gas discharge. Theelectric field distribution in the discharge space is calculated by finite element method,at the same time, use Poisson equation to solve the distortion effect of electric field.In the process of simulation, elastic collision, excitation collision and impactionization between the electrons and the atmospheric molecular has been fullyconsidered.Surface charge accumulation of composite insulator under high voltage DC hasbeen measured in experiments, and Compare the similarities and differences betweenthe simulation results and experimental results.The simulation results can provide a good explanation for the process of gasdischarge in atmospheric environment, and the simulation is important for theoreticalresearch on the mechanism of this kind of gas discharge.