Transmission Network Planning Based On Discrete Artificial Fish School Algorithm

Transmission network planning is an important part of power system planning. The task of transmission network planning is to figure out the optimal network structure according to the load increasing and the power plant planning during the planning period. Transmission network planning can be divided into two stages, scheme forming and scheme evaluation.Research on scheme forming includes two aspects: one is to build up reasonable planning models; the other is to give an appropriate solving algorithm. Considering the character of transmission network planning, the artificial fish school algorithm(AFSA) is proposed to solve single-stage network planning in this article. In order to improve ability of solving discrete optimization problem, the discrete artificial fish school algorithm(DAFSA) is designed which is applicable to transmission network planning. Due to the existence of local extreme, tabu search(TS) algorithm is introduced. The hybrid algorithm can recognize, record and jump away from the local optimal solution. In this way, the reduplicate search can be reduced furthest, and the computation efficiency is greatly improved. The example results show that the new method has high computation efficiency and good local & global convergence.The task of scheme evaluation stage is to evaluate and compare the forming schemes, and to make the final decision. Security, reliability, economy and flexibility must be considered in evaluation. In order to solve the difficulty of weight which depends on subjectivity in comprehensive fuzzy evaluation, an entropy weight method is introduced, the weights of the factors are determined voluntarily according to the suggestions of experts. Comprehensive fuzzy evaluation model applied to transmission network planning evaluation is established, by means of the improvement to synthesis operator, take full advantage of all information of each indicators, and the evaluation results are more easily distinguished. Example results show that the proposed comprehensive fuzzy evaluation method is clear in theory, convenient to calculate and its result is intuitionistic, thus the proposed method is available for practical application。...