Electric Utility

One 115kV Breaker and 7.5/10 MVA Substation

This substation was somewhat unique in that the client wanted to be able to sectionalize the 115kV line with line relaying looking in both directions using one breaker. The protection for the transformer uses an S&C 115kV circuit switcher. The breaker is located on the south side of the substation tap and a three phase disconnect switch is located north of the tap. If the breaker trips for a fault south of the station, the sub is not effected. If the breaker trips for a fault north of the breaker, the three phase switch can be opened by SCADA and the breaker can then be closed, thus restoring the substation to service. The transformer pad and oil containment are designed for a future 12/16/20 MVA transformer. The secondary uses the T&D main and transfer bus vertical configuration. Initially two feeders are being used with two for future use. Note the control house is a prefabbed decorative concrete building. The transformer high side is dual voltage 115kV X 69kV and currently operating on 69kV.