The Influence Of Network Equivalence On Power Transmission Cost

Following the innovation of power system, the disjoin of transmission and distribution is the trend of developing after disjoin of Generation and Grid. Network equivalence is an effective way to reduce the power flow computation burden. Whether the transmission cost of power network after equivalence will vary is a new problem in the realm of electricity market research. This paper develops a computation model of transmission cost based on power distribution theorem ( power distribution theorem is that the consumed power for arbitrary branch of the electrical network equals the summation of elements provided by each source with different distribution coefficients) and branch transmission cost conservation( the cost of branch inflow equals that of branch outflow). It shows that the transmission and distribution cost before and after the network equivalence will be different. A case study on IEEE 30 bus system verifies the proposed method.