Interconnection of Power and Railroad Traction Systems by Means of Frequency Changers

Several types of variable ratio frequency-changers are discussed and installations of such apparatus on the electrified section of the New York, New Haven & Hartford Railroad are described in some detail. These types of frequency-changers permit a flexible tie between interconnected systems, and accurate and automatic control of load regardless of variations in voltage or frequency in either system. Any desired constant load transfer in either direction may be obtained through the apparatus by manually setting a load regulating relay. Provision is made also for operating the sets as synchronous condensers to improve power factor. The functioning of regulating machines and auxiliary equipment to obtain the desired results is explained, together with a description of switching equipment installed in connection with the main units.