Abstract: The success of privatization of most of the industries led people to think for the deregulation of electric power system. This results in restructuring of currently vertically integrated utility (VIU) to the different zones. Due to this worldwide deregulation or privatization process, the electricity industry has undergone drastic changes and has significantly affected energy markets. In a deregulated power market, the optimum power flow (OPF) for an interconnected grid system is an important concern as related to transmission loss and operating constraints of power network. The increased power transaction as related to increased demand and satisfaction of those demand to the competition of generation companies (GENCOs) are resulting the stress on power network which further causes the danger to voltage security, violation of limits of line flow, increase in the line losses, large requirement of reactive power, danger to power system stability and over load of the lines i.e. congestion of power in system. More often than not, pool market results originate network congestion in the transmission lines which is one of the technical problems that appear particularly in the deregulated environment. This paper reviews some of congestion management (CM) methods including generator rescheduling, FACTS devices and demand response. Each technique has its own significance and potential for management of congestion in a deregulated power system.

Keywords: Congestion, power system deregulation, generator rescheduling, FACTS devices, demand response.