Static Frequency Converter for SEPTA's Wayne Junction Traction Substation

In Philadelphia and its vicinity the Southeastern Pennsylvania Transportation Authority (SEPTA) operates a rapid transit commuter system known as the Regional High Speed Lines. This system has two divisions: Philadelphia Division (formerly Penn Central) and Reading Division (formerly Reading Railroad). In the next few years the electric traction power demand of the Reading Division is expected to increase, and therefore, additional power supply capability is required. The system is supplied at 25 Hz by frequency converters located at Wayne Junction substation, and the power augmentation could be achieved either by tapping power from the Amtrak system or by installing additional frequency converters. For both technical and operational reasons, the converter alternative was preferred; the project associated with provision of the first such unit is described. Two types of equipment were considered: conventional rotary converters and modern thyristor operated static converters. The new equipment was required to be fully compatible with the existing rotaries and backup line, to be available for scheduled operation by November 1984, and to be designed to have a low life cycle cost. A detailed technical and economical analysis indicated that the static frequency converter was the most suitable type, and a specification for its design and manufacture was prepared.