Transmission Line Maintenance Scheduling Based on Graph Coloring

In order to improve the efficiency of transmission line maintenance scheduling, a multi-objective and multi-scale mathematical model is proposed. The coloring problem of graph theory and analytic hierarchy process are combined, and various constrains are considered in the model. In order to deal with discrete variables problems, a new method based on harmony search algorithm combined with ant colony algorithm is proposed. The harmony search algorithm is developed based on an analogy with music improvisation process. Musical performers seek to find pleasing harmony as determined by aesthetic standard, just as the optimization process seeks to find global optimization solution. Harmony search algorithm is suitable for solving the problem of continuous variable problem, so it is improved in this paper. The number of color got by using ant colony algorithm is the first stage, and the coloring order obtained by using improved harmony search algorithm is the second stage. Furthermore we discuss the application of our models to a case, and simulation results show that the proposed model and algorithm are effective.