Surge Protection Of Cable-Connected Equipment On Higher-Voltage Distribution Systems

摘要

Since the 1969 presentation on protection of cable-connected distribution equipment, 15 kV and below, the working group has studied systems of 25 kV and 34.5 kV voltage class. Considerable information on field experience has been gathered. Analytical and experimental work has been done on the determination of attenuation of surges in cables. Various protection methods have been discussed and laboratory tests and analyses performed. The working group concludes that for the BIL's being used with the higher distribution voltages, protection can be provided with an arrester at the overhead line-cable junction only, with some limitations, for 25 kV class, 125 kV BIL systems. For 34.5 kV systems with 125 kV or 150 kV BIL, other protection methods must be considered.