Cogeneration 530MW

Bath Engineering Corporation represented the owner of a 530MW cogeneration facility at ERCOT-ISO meetings on electric utility deregulation matters.  Bath provided feasibility studies for the interconnection of 500MW’s of generation to the electric utility power grid and provided conceptual designs for a 138kV double bus substation to interconnect 500MW’s of co-generation to the electric utility grid and to the thermal host’s 60MW load.  This assignment required power flow and short circuit studies to arrive at a conceptual design and to size transmission lines and high voltage switching equipment.  For the 138kV line design, Bath specified SEL-311L and ABB REL 356 protective relays for the protection of three 138kV line segments.  Short circuit studies were performed and the results were used to calculate settings for current-differential relays, PVD and KAB bus differential relays, under voltage relays, motor differential relays, ground relays, motor overload relays, and motor starting relays. The current-differential relays used fiber optic lines for communications.