Algorithms for incorporating reactive power into market dispatch

Abstract

This paper proposes some methods for incorporating reactive power dispatch into nodal pricing and dispatch algorithms in pool-based electricity markets. The current approach of dispatching real power using a simplified power flow model and subsequently allocating reactive power as an ancillary service has the problem of getting suboptimal and some times infeasible solutions. However the complete a.c. power flow formulation can lead problems, due to non-convexity and resource limitations. This paper proposes an improvement to the standard decoupled linear formulation approach. In the proposed method real power is dispatched first and then reactive power is dispatched allowing small changes to real power dispatch. The results of case studies show that this method gives similar results to the full non-linear solution for real and reactive power dispatch and prices.