Optimal Congestion Management in Deregulated Power System

Abstract

The structural arrangement and the operation of electric power industry have been completely changed since last few decades. This restructuring of the power industry has been done to initialize market competition among the various participants to enhance market profits. In a deregulated utility system the generation, transmission and distribution systems work as independent entities and it becomes hard for a system operator to maintain the synchronism among all the systems especially when congestion or line outage occurs. If the congestion persists for a long time, it may harm system security and reliability. Optimal congestion management must be done to alleviate the congestion so that market efficiency, stability and reliability do not alter. Numerous methods are available in art of literature to relieve the congestion. These are broadly classified as convention methods and optimization methods. The conventional optimization methods of congestion management perform perfectly if the objective function has good continuity and differentiability. As the congestion management is a nonlinear complex problem, the conventional optimization methods are not well suited as tuning of assessment weighing factors is a laborious task. The solution of nonlinear optimization problems completely confine on the weights, so the optimization methods are more appropriate for congestion management. The main objective of the thesis is to develop an optimized congestion management methodology in restructured transmission system in order to optimize the congestion cost in deregulated environment. Thesis also aims to determine the optimized location of Unified Power Flow Controller (UPFC) device under severe line outages conditions. The main purpose of the thesis is to develop the hybrid optimization algorithms, which can yield only the feasible solutions of congestion management cost over the entire searching area.