Allocation Of Congestion Cost Using Imputation Of Branch Power Flow Method

The practice of electricity market is the inevitable trend of electric industry in developing, which results in the change of the conventional power system in organization, and causes a series of new problems such as transmission congestion. Transmission congestion is a very important issue in power market. The limitation of transmission resources gives rise to power transmission bottleneck. It limits the free competition in power market. If we hope that the substance of market competition can be embodied, and to improve the efficiency of electric system as well as optimize resources, we must take efficient measures to manage transmission congestion. How to develop a logical method for congestion cost allocation becomes an important task.Firstly, this paper expounds the management of transmission congestion in detail, introduces the use of congestion management system in abroad regional electricity market, and analyses commonly used approaches of congestion cost allocation, Use this as a foundation, a new idea that applying the imputation of impedance branch dissipation power to determine the congestion cost allocation is advanced.Based on the new idea, the paper presents a novel algorithm of imputation of an impedance-branch power flow that based on the theory of imputation of an impedance-branch dissipation power. Independent of the change of the slack bus, the algorithm can reflect the influence of power flow by random transaction, and set up the mathematics relationship between every transaction in system and branch power flow physically. Combination the optimal power flow model which makes minimization of congestion cost as the objective function, a novel method for allocation of congestion cost is developed. Simulation results in IEEE-14 bus test system indicate that the congestion costs proposed based on liability among consumers and providers, and don't lead to the Phenomeno of surplus allocation;the proposed method satisfies the physical features and is applicable for arbitrary configurations of transmission networks,and can impute the congestion costs to individual transactions naturally and simultaneously, which Independent of the order of transactions.