Study On Available Transfer Capability Based On Bacterial Colony Chemotaxis Algorithm

In power market environment, Available Transfer Capability (ATC) of power system is important index of transfer capability and system security. Because of the factors of environment and land availability consideration and the maximizing effects of equipments etc, the load level of modern power systems has become more and more serious. The problem of how to ascertain power system transmission capability of areas accurately has become an important issue for system researchers to concern.After reviewing the transfer capability study history, this paper studies transfer capability calculation under static constraints, establishes an Available Transfer Capability model based on Optimal Power Flows (OPF). With the advantages of distributed parallel searching ability, strong robustness, good global astringency and easy implementation and etc, Bacterial Colony Chemotaxis (BCC) Algorithm is employed to solve this model. The optimization of n-dimensional problem was simplified as the optimization of n-1 sub-problems of 2-dimension by presenting the new formulation. As for the searching characteristic of a cell and colony, the author introduced self-adaptive step strategy. the strategy automatically adjusted the step length and the direction of bacterium;The bulletin can remain the best direction of bacteria which may be abandoned at random. These strategies above improved the convergence speed and the capability of searching the global minimum. Functions are used to improve the validity of this proposed algorithm.The verification results by IEEE-30 bus system show the algorithm has the stronger global convergence performance and the quicker convergence speed compared with the results gained by benders decomposition and improved particle swarm optimization (IPSO), and it is proved to be available.