Non-uniform pollution on insulator surface affects its electric properties. In field operating conditions

the pollution on insulator surface may distribute non-uniformly between windward and leeward sides

leading to a lower flashover voltage gradient according to artificial pollution tests. Thereby

we proposed a calculation method for the residual pollution layer resistance of windward/leeward side non-uniform polluted insulator

established a dynamic model for the corresponding insulator dc flashover

and experimentally carried out verification. Then

using this model

we calculated and analyzed the leakage current as well as dynamic residual pollution layer resistance under different pollution non-uniformity. Research results indicate that

during insulator dc flashover

the residual pollution layer resistance can be lowered by 50% under windward/leeward side non-uniform pollution compared with that under uniform pollution condition. The effect of leeward side area ratio T is less than that of windward/leeward side non-uniform ratio J on insulator dc flashover process. Research results can provide certain references for the better configuration and selection of transmission line external insulation.