Case Study

115kV bus upgrade

Client challenge:

Our client required a 115kV bus upgrade at an existing substation for capacity purposes and a design for a auto-reclosing/bus restoration scheme.

Technical summary:

SGC Engineering were commissioned to upgrade the strain bus which involved evaluating the steel structures to ensure that they could handle the increased weight. This also included adding an auto-reclosing scheme design to restore the 115kV bus after faults associated with the two existing 115/34kV power transformers connected to the bus.

The 115kV bus was upgraded from a single 1590 ACSR conductor to dual 1272 ACSR conductors. The 115kV bus tie switch J123 was replaced with a 3,000 amp switch. Insulators associated with the bus upgrade were also replaced. The analysis of the existing steel structures resulted in new steel structures being designed and installed outside the substation yard to reduce the line tensions on the existing substation structures.

How we helped:

Our team was responsible for the substation design for the bus upgrade as well as the necessary changes for the auto reclosing scheme. The team submitted the design at 30%, 70% and 100% completion, along with an issue for construction design and final record drawing submittal. SGC also completed all required protection setting changes for the auto-reclosing scheme and provided construction support.

Powerful results:

Our team completed the project on time, under budget and there were no notable issues with the final design. The client was pleased with the final product and has continued to utilize SGC on subsequent substation projects.