Novel method of determining Transmission Congestion Cost under Restructured Power System Environment

Abstract

The problem of transmission congestion management and pricing has been identified as one of the critical and important tasks of the System Operator (SO) for the smooth functioning of restructured electricity markets. In this paper, new procedure is proposed to determine transmission congestion cost which comprises of rescheduling cost of generators involved and change in transmission utility cost. An effective transmission congestion relief procedure has been developed through generation rescheduling. Managing congestion is achieved by rescheduling of generating units based on grouping method using Transmission Congestion sensitivity Factors (TCSFs). Congestion management is formulated as an optimization problem and Particle Swarm Optimization (PSO) is applied for solving. Change in transmission utility cost is the difference in transmission utility cost during and after relieving congestion. For the determination of transmission utility cost, contributions of each generator or load on the actual power flow in the lines are determined employing power tracing algorithm. Proposed procedure is validated by determining transmission congestion cost for IEEE 6 bus system. The results obtained are quite encouraging.