Design of a 138 kV gas insulated substation for a large industrial cogeneration facility

The author describes the design of a 138 kV GIS (gas insulated substation) installed as part of a large industrial cogeneration facility. Special design features required to accommodate the GIS are discussed. Particular attention is given to surge protection and differential settlement criteria. It is concluded that effort expended during the design phase to ensure coordination among the suppliers of the GIS, generator step-up transformer, and 138 kV cable paid off during the installation phase. Installation of the GIS was completed on schedule, and interfacing to the cable and the transformer went smoothly.<>