A new user-oriented method for congestion cost allocation

The existing transmission congestion cost allocation methods are almost based on DC flows. The interaction between P-Q is generally neglected due to its complexity. In addition, the congestion cost is allocated just to consumers (nodal loads). To improve the accuracy and equitability of the existing methods, a new user-oriented congestion cost allocation method is proposed. A novel definition of using portion of a power element by a particular generator is presented based on direct AC flow tracing. The system congestion cost is allocated to relative lines, and then to individual generators according to their contributions to system congestion. At last, the congestion cost a consumer has to pay is determined by its active components absorbed from individual generators. The proposed method eliminates not only the merchandising surplus, but also the mutual compensations. It gives correct economic signals to both generators and consumers. The P-Q interaction is taken into account accurately. Simulation results show that the proposed method is powerful and effective.