TMC Breaker Replacement Program

Challenge: Improve electric reliability on feeder circuits across service territories.

Solution: Milhouse engineered the physical design of new medium voltage circuit breakers and regulators as the client prescribed and prepared the control design associated with the feeder relays.

Result: Boost in reliability for both the circuit and the region.

The TMC breaker replacement program includes the replacement of 12kV through 46kV breakers at several substations, selected based on equipment aging condition and operational performance. Depending on the site/breaker, this scope has expanded to include modifications and additions of yard disconnect switches, regulators, and battery systems. Relay upgrades to modernize protection and align with current relaying standards are also common in this program, as well as coordination and modification of site SCADA systems in conjunction with the Georgia Power SIA department.

Milhouse provided design services for replacing the existing oil breakers with modern vacuum or SF6 gas circuit breakers. Design services included the following:

» Coordination with Georgia Power construction managers, control, and physical design engineers to determine each site’s scope and design criteria.
» Design of plan, sections, grounding, and raceway prints to show modifications.
» Design of one-line, three-line, front views, and DC schematics to show modifications.
» Development of Bills of material, including the requisition of Stock and non-stock materials.
» Construction support as required.

In addition to the above equipment, Milhouse was involved in designing the following:
» Feeder regulators
» Lightning arrestors
» Feeder Disconnect Switches
» Yard AC/DC panels
» Yard RTU cabinet
» Feeder protection relay panels