Design of the First 500-kV Substations on the Southern California Edison Company System

The design of two new 500-kV substations has been completed and is discussed in this paper. The discussion of the design covers first a description of the 500-kV grid of transmission lines and substations that will serve as a support for the existing 220-kV system. Following the description of the new system is a discussion of the substation design criteria. The areas covered are insulation coordination, line and bus arrangement, bus conductor selection, and equipment requirements. The paper concludes with a description of the stations.