Equivalent line limit calculation for power system equivalent networks

This paper focuses on the relatively unexplored subject of creating limit-preserving equivalents (LPEs). There is a push to develop LPEs for power system interconnections to be used in markets and reliability studies. The equivalents that exist for these interconnections do not capture thermal limits of equivalent lines, which results in their transmission limits being significantly different from the original interconnection limits. Assigning noninfinite and nonzero limits to equivalent lines is the niche of this paper. This is done by considering an unloaded network, which is operating point independent. A solution method is developed and discussed, which is capable of assigning lower, best, and upper estimates for equivalent line limits and is proposed for use towards developing LPEs.