Stability Limited Load Supply and Interchange Capability

Traditional load supply and interchange capabilities represent maximums based on steady state generation, line flow and voltage constraints. If the system cannot survive a list of transients when operated at these capabilities, the current computational algorithms do not provide a means for systematically determining alternative secure capabilities. In this paper, the recent results in direct stability methods are applied to give reasonably rapid solutions to this problem. The concept of a Potential Energy Boundary Surface (PEBS) is utilized to obtain transient energy stability margins and their sensitivity to load levels. The energy margins and their sensitivities are used to direct a systematic search for approximate stability limited capabilities.