Field and Laboratory Tests of Contaminated Insulators for the Design of the State Electricity Commission of Victoria's 500-kY System

The results of field and laboratory tests on contaminated insulators, made to determine insulation level of the State Electricity Commission of Victoria's 500-kV transmission system, are presented, including performance of 220-kV lines operating in a very heavy contamination area, field measurements of the pollution and insulator flashover mechanism, development of artificial pollution for laboratory tests, and the use of this pollution for power frequency and switching surge tests at the General Electric Pittsfield High Voltage Laboratory. Test data include curves of power frequency and switching surge flashover levels versus contamination severity; power frequency flashover versus string length; and the results of high-speed motion picture tests made to determine the basic mechanism of critical surging and flashover on contaminated insulators, plus a theoretical explanation of this mechanism.