High voltage direct current (HVDC) energy transmission has solved the problems of deliverying electric power of large capacity over long distances. During the operation of DC excitation, large amount of charges inevitabley accumulate on insualtion surface, posing a hazardous effect on surface insulation performance. How to effectively control surface charge accumulation still remains as a chanllenge that we must face. This investigation proposes a partially high conductive cotaing method for regulating surface charge distribution on spacers, aiming at obtaining an excellent surface insulation strength of DC spacers. It is hoped this research could provide valueable referances for designing insulation structure of DC power equipment.
 

surface charge