Surface charge pattern analysis based on the field-dependent charging theory: A review

Surface charge pattern analysis on HVDC insulators is a difficult task, which requires a comprehensive understanding of the physical mechanisms of surface charging. This paper provides a review on surface charge patterns and related models published within the past 30 years. In addition, based on the field-dependent charging theory, the research differences of various surface charge patterns obtained by previous researchers are explained. Difficulties and future prospects in modeling of surface charging phenomenon are also discussed. This paper may be used as a reference for the analysis of charge accumulation patterns and it would be helpful to researchers to compare and understand charge accumulation results published by earlier researchers.