Dynamic analysis of DC GIL insulator surface charge accumulation based on COMSOL and MATLAB co-simulation

Insulator surface charge accumulation is one of the main limiting factors of DC gas insulated pipeline transmission lines (DC-GIL). At present, the analysis of surface charge accumulation mostly uses the finite element analysis software to calculate directly, but there are some shortcomings such as slow simulation and poor data processing ability. Therefore, this paper proposes a method to calculate the gas side charge density based on time-varying power flow. Through the co-simulation of COMSOL and MATLAB, the fast calculation, flexible program call and data processing of partial differential equation are realized. The transient and steady-state characteristics of surface charge accumulation of DC GIL basin insulator under different solid conductivity are calculated. The influence of voltage and gas ion generation rate on the type, quantity and steady-state time of insulator surface charge accumulation are analyzed. Finally, based on the insulator structure in this paper, the limit solid conductivity of which the surface charge accumulation is not affected is calculated.