Reactive power procurement model in electricity markets based on normalized effective reactive power reserve

Abstract

SUMMARY As one of the important security criteria, power system operators closely monitor reactive power reserve in voltage control areas (VCAs) of their system to ensure voltage security and to prevent voltage collapse. Therefore, from a system/market operator perspective, proper management of reactive power reserve must be considered in reactive power procurement stage. This paper proposes a long-term procurement model to meet reactive power reserve requirements in competitive electricity markets considering both economical and technical issues. The model would be of interest to system/market operators since it is based on a new indicator referred to as normalized effective reactive power reserve (NERPR) as a more meaningful signal compared to other physical/economical indicators. The proposed framework for reactive power procurement determines accepted bids by minimizing the associated procurement cost while maximizing NERPR in each VCA of the system. Physical constraints such as generator capability curves and voltage security are taken into account in the formulation. Also, a population-based algorithm is introduced here to solve the mixed integer non-linear programming (MINLP) problem resulted from the procurement model. An algorithm is proposed to change the MINLP problem to series of NLP sub-problems. The CIGRE 32-bus test system is used to test the feasibility of the proposed procurement model. Copyright © 2013 John Wiley & Sons, Ltd.