Electrical Features of the Conowingo Generating Station and the Receiving Substations at Philadelphia

The paper outlines the principal electrical features of the Conowingo development. This includes a description of the main units and their connections, and an outline of the station auxiliary supply and the 220,000-volt substation which it was necessary to build on the roof of the power plant. A description is included of the 220,000-volt substation at Plymouth Meeting, the Philadelphia terminus of the Conowingo lines, as well as the lines of the Pennsylvania-New Jersey Interconnection. At this substation are located the 30,000-kv-a. synchronous condensers installed for stability purposes, as well as a 66-kv. installation. Three winding 220/69/13.3-kv. self-cooled transformer banks of 130,000-kv-a. rating, arranged for tap changing under load, are installed here. A description is also included of the Westmoreland Substation where the 66-kv. lines from Plymouth Meeting tie in with the 66-kv. ``backbone´´ of the Philadelphia Electric System. At this substation, 30,000-kv-a. synchronous condensers for power-factor correction are located, as is also an extensive 13,200-volt installation for controlling transmission lines to various distribution substations.