In this quarters Orbital Technical Bulletin, we would like to highlight our experience with SUBSTATION GROUND SWITCH REPLACEMENTS. The purpose of this program is to remove existing 34kV and 69kV ground switches and replace with new protection devices.
Substation Ground Switch Replacement Project
On this project, two 34kV ground switches were demolished and replaced with two new Trans-Rupter II assemblies.
Scope of work included:
- Demolition package for existing ground switches
- Assist with selection of most appropriate equipment, considering available space, existing equipment condition and configuration, new equipment and installation costs, and other assessment criteria
- Installation package for new Trans-Rupter II protection devices included:
- Civil/Structural
- Fence modification and site work drawings for site expansion
- Structure Plan View revisions
- Structure Elevation/Section View revisions
- Foundation drawings/sections/details for new Trans-Rupter II
- New steel detail drawing and modifications to steel structure to allow for mounting of lightning arresters
- Electrical
- Single Line
- Phasing Diagram
- Cable Layout and Tabulation
- Grounding
- Wiring and Schematics
- Switchgear modification
- Civil/Structural
In summary, by replacing the high-speed ground switches with Trans-Rupter II protection devices, transformer faults are kept local to the substation and do not affect the transmission line relaying or breakers. This minimizes loss of service for customers and puts less stress on the transmission system.
