Study Of The Theory And Methodologies For Allocation Of Transmission And Distribution Losses In Electricity Markets

The power loss in transmission system is generally 5%-10% of the total system generation. Of course, the power loss in distribution system is bigger than that in transmission system. In electricity markets, these losses are parts of the cost in power transmission and distribution, and should be allocated to all participators using the power grids. As a result, that how to allocate the losses to all participators in an equitable way has become a key issue affecting the well construction of electricity markets. Based on electric circuit theorems and calculus and cooperative game theory, the theory and methodology for branch's losses allocation are studied in depth. Then, two new methods for transmission losses allocation, and a new method for distribution losses allocation are proposed successively.Based on the electric circuit theory, the basic natures and requirements abided necessarily in transmission loss allocation are presented at first in this dissertation. According to those natures, the merits and defects and applicability inherent in four currently widely used methods for branch losses allocation are analyzed in details. Based on the definitions of real and reactive currents into a bus due to a generator, a new method is derived theoretically to determine branch's complex loss components induced by individual generators' active- and reactive-power, respectively, using the concepts of total differential and definite integral. The interaction between real and reactive powers is considered directly in the calculation of loss components. As a result, a new method for branch's losses allocation is proposed based on calculus.General principles for element's (line and transformer) complex loss allocation to individual generators are proposed based on the proportional sharing principle. A new method for allocating complex losses in power elements with multi-equivalent series and parallel branches is derived resorting to newly proposed branch's losses allocation method. Then, the traditional flow tracing method, applicable for only one lossless flow, is extended to applicable for two different kinds of lossy flows (P and Q flows). A new complex loss allocation method, called lossy complex power tracing method (LCPTM), is proposed, which is applicable for arbitrary configurations of transmission systems. The impact on losses allocation of interaction between active and reactive powers is well considered in this method. The new method is concise and easy to implement. It overcomes defects of the existing tracing methods, such as need transplanting all parallel (or shunt) branches, making fictitious lossless networks and tracing P/Q flow in a decomposition way.Based on a solved load flow, each source and load in a transmission system is modeled by its equivalent injection current source. A two-step cooperative game is specially designed to allocate the transmission losses to all sources and loads. By...