Time-Error Control for Interconnected Synchronous Electric Power Systems

A group of synchronous machine sets may enjoy the operating advantages of time-error governing in regard to accurate load division and at the same time be coupled through a tie line to a much larger system. The method of governing of the larger system is not important and the tie-line power transfer can be kept at any schedule value with a controller. Two time-error-governed areas may be linked by a tie line in which the power transfer can be kept to a schedule value while each area supplies only its own load deviations; to do this, angle-sensitive tie-line controllers are required. The paper describes the operation of a miniature power system built to solve problems arising when synchronous machines are controlled in the foregoing manner. The detailed operation of the angle-sensitive tie-line controller is also given, together with system-operating results of an exploratory nature, both computed and from the miniature system.