Research On Models Of Power Flow Tracing And Congestion Management In Electricity Market

Electricity market is the inevitable trend of electrical industry in developing. It results in the change of the conventional power system in organization, and causes a series of new technique problems. This paper focuses on three aspects of transmission management of electricity market: loss allocation, transmission cost allocation and congestion management.Allocating power loss in transmission networks to each participant fairly is one of the important contexts of transmission management. The nonlinear of loss allocation decides the complexity of model. Firstly, from the view of methodology, the present loss allocation algorithms are classified, compared and analyzed, and the advantages and disadvantages of each method are expatiated. The problems should be paid attention to in the process of loss allocation or need in-depth study in the future are also discussed. The difficulties of loss allocation in different electricity markets are pointed out clearly, and the principles a good loss allocation algorithm should follow are proposed in the end of first part.Most of existing methods based on power flow tracing can't allocate loss fairly between generators and consumers. This paper presents the concepts of equivalent generator-current (EGC) and equivalent load-current (ELC), and a new model and algorithm based on current decomposition and bi-directional trace. By tracing the real and imaginary current respectively, all participants'current components in each branch can be calculated on the basis of EGC and ELC. The loss caused by capacitive charging of transmission lines also can be allocated completely by regarding the current in the parallel branch as GC or LC. By down-stream and up-stream twice trace, transmission loss can be allocated to all the generators and consumers and the ratio of loss between them is determined by the operation modes of power system and their electric positions. It can be used in both Pool and Pool-bilateral electricity markets, and also can be applied in the systems with circular flow. The calculation process is demonstrated by IEEE-14 test system. The results of several test systems show the efficiency of this method, such as 5-bus, IEEE-30 and WSCC-9 systems. And the new algorithm is compared with six typical ones.After open access, allocating transmission cost impartially is necessary to keep the healthy development of electricity market. The usage-of-transmission-system (UTS)...