Refurbishment Strategies for Conventional SVC Stations utilizing Modern Control Cooling and Thyristor Valves and selective main Circuit replacements
By: Roger Broberg and Dr. Afshin Samadi from ABB AB. Andrew Laughlin and Russell Thornton from Chugach Electric Association. Mark Reynolds and Brian Furumasu from POWER Engineers.
Refurbishment of SVCs can be accomplished in many forms and construction sequences. This discussion focuses on a cost effective replacement and technology upgrade of two SVCs that are very important to the voltage stability and increased power transfers in the Southern part of the Chugach Electric Association (CEA) power system, interconnected network. Owned by the State of Alaska, the SVCs are operated and maintained by CEA. The original SVC Project in the early 1990s had a major requirement for Power Oscillation Damping (POD) functionality, and initially staged fault testing verified the proper settings and coordination of SVC control actions to provided improved system damping. Part of this discussion is focused on the predicted and field measured responses of the changed network conditions since the original 1993 in service date and an example of how to verify SVC performance with limited ability to stress the network.
A second related discussion is focused on the initial business case development and the execution of an Engineer Procure Construction (EPC) type engagement for a rapid change-out of the major components of the SVC including cooling systems, thyristor valve assemblies and the control system to accomplish both the normal and POD operation.