Determination of transmission interface transfer limits

Wheeling of electric power from one region to another has been common for many years. However, the ability to transfer power in this market is very often limited by the maximum power that can be securely transferred across one or more transmission interfaces. In the past decade, the ability to identify and quantify power transfers on the transmission network and the cost implications has become increasingly important. This paper discusses a methodology to determine the simultaneous transfer limits considering several interfaces in a transmission system. Using a production cost model that incorporates a transmission power-flow representation, it is possible to estimate the frequency and magnitude of power flows across interfaces while locating restrictions. This analysis is done for a sample system and for a study of New England.