Research And Application Of Transmission Network Expansion Planning Based On Ant Colony Algorithm

Transmission network expansion planning is a very complex combination optimization problem, which is large-scale and nonlinear , and reasonable transmission system structure is the material foundation for the power system to operate with safety , reliableness and economic circulation. With the growing scale of the grid, the dimension of the decision variable increasing rapidly,the planning problem is becoming increasingly complex. Comparing with the traditional methods, which of mathematical optimization calculate with more time and low efficiency, Ant Colony Algorithm is an efficient heuristic search technology to solve combinatorial optimization problems. It has strong robustness, well distributed calculate system, and easy to combine with other algorithm. Now it has been successfully used in many optimization problems.In this paper, the research situation of transmission network planning is introduced, and the existing methods of planning are summarized. The theory and the model of ant colony algorithm are emphatically introduced. Furthermore, an improved adaptive ant colony algorithm is also expressed, which is effective to reduce contradictions between global optimization and searching efficiency of ant colony algorithm.In this paper, a transmission network planning mathematical model is brought forward, which includes building cost and running cost. And overload pentalty function and "N-1"overload pentalty function are added in. The author makes the computing program by using matlab.Practical examples such as a 6-bus systerm and a 18 bus system have proved the superiority of the improved ant colony algorithm in transmission network expansion planning.Practical examples as a 110kv system of one county of Guangxi have proved that the resultes were superior to the programs that planned by traditional method.