ALLOCATION OF TRANSMISSION LOSS IN DEREGULATED POWER SYSTEM NETWORKS

Abstract

Deregulation in the electric power industry is having sweeping consequences for energy markets. Consumer choice and the changing role of the electricity industry in the marketplace have created new challenges that have to be addressed. New planning, operating and marketing issues related to deregulation are evolving and these issues are being addressed. Although the concept of deregulation has stemmed from the desire for a competitive wholesale power market, the implementation of deregulation means different things to different utilities depending upon the socio-economic structure of the region where the utilities reside. Full deregulation allows bilateral contracts between the suppliers and the buyers. This also leads to non-discriminatory open access to unbundled transmission and distribution networks and abolition of region based monopoly systems. The supervisory control is required for system security and reliability purpose only. This concept, however, leads to the confusion of transmission loss sharing and generation of the reactive power. Each transaction would cause some transmission loss and thus needs some reactive power to maintain the voltage profile in the system. Two methods have been developed to determine a generator's share of transmission loss in a fully deregulated power system. They are the Incremental Load Flow Approach (ILFA) and the Marginal Transmission Loss Approach (MTLA). The ILFA is a very simple and straightforward approach that employs an iterative load flow technique. The MTLA proposes a splitting of transmission loss starting from a generalised transmission loss expression and finds the transmission loss share of a generator by utilizing the marginal rate of transmission loss. Results obtained from both approaches agree well. The computational time required by the ILFA is more than that of the MTLA. The details of the two methods along with numerical results have been presented in this thesis.