Security-constrained price-based unit commitment in the deregulated power market

This paper describes a coordination process between GENCOs and the ISO for congestion management and reducing the risk of failure to supply loads. The algorithm underlining the coordination technique is the security-constrained price-based unit commitment (SPUC) which is implemented in two states. At first, GENCOs apply priced-based unit commitment (without transmission security constraints), schedule their generating units and submit their energy and capacity bids to the ISO for maximizing their revenues. The ISO obtains transmission information as well from TRANSCOs via OASIS. Using the two sets of generation and transmission data, the ISO executes inter-zonal and intra-zonal congestion management and contingency analysis for minimizing line flow violations and the risk supplying loads. As part of this package, the ISO would have a chance to minimize both transmission flow and reactive (bus voltage) violations. If transmission flow violations persist after the adjustments are made, the solution would provide a signal to GENCOs, based on Benders decomposition, for modifying their initial bids. Accordingly, additional constraints will be introduced in GENCOs for rescheduling generating units and submitting modified bids to the ISO.