EPRI-HVDC INSULATOR STUDIES - 2. LABORATORY SIMULATION STUDIES.

Utilizing field data laboratory studies to simulate flashovers on several insulator shapes and designs were carried out. Chemical composition of the contaminants used in these studies was based on findings at the Sylmar HVDC Converter Station. The flashover characteristics thus derived are compared with those using only sodium chloride as the contaminant. It can be shown that the flashover voltage for a multicomponent contaminant mixture can be predicted by assuming linear independence between the individual component salt. The chief differences between dc and ac flashovers are also outlined. The relationship between the flashover voltage and the surface conditions of an insulator was investigated.