Studies On Optimization Of Global Generation And Transmission Maintenance Scheduling And Its Security Correction

Global generation and transmission maintenance scheduling and its security correction are important issues closely related to planning and design of power system and operation dispatch. With the continuous expansion of power grid and the development of electricity market, optimization for global generation and transmission maintenance scheduling and its security and strengthen the security of power grid operation, has the important theoretical and practical significance. In the actual system, in order to ensure reliable operation of power system, at the same time of maintenance scheduling formulating and security correction, the load transfer programs should be determination. While in the implementation of maintenance scheduling, switching operation should be carried for the load transfer. Based on this, this paper study on the optimization model and algorithm of global generation and transmission maintenance scheduling and its security correction which considering the load transfer. Specific contents are as follows:Firstly, an optimization model for global generation and transmission maintenance scheduling is established considering the load transfer, and immune genetic algorithm is proposed to solve the problem. A load transfer equivalent model is established consideration the load transfer method between associated substations, and to analyze and refine the global generation and transmission maintenance scheduling specifies the basic principles and various factors, the establishment of multi-objective multi-constraint and global generation and transmission maintenance scheduling optimization model. As for immune genetic algorithm of global generation and transmission maintenance scheduling, taking into account the contradiction between the multi-objective nature, a target relative dominant method is proposed to solve the optimal solution. Then according to global generation and transmission maintenance optimization model features, antibody encoding, computation affinity, antibody inhibition and promotion of crossover and mutation operator four aspects of algorithm is improved to ensure the effective of algorithm.Secondly, an optimization model of maintenance scheduling security correction considering the load transfer was established. And a hybrid algorithm was combined by semi-smooth Newton method and immune genetic algorithm to solve the model. According to the characteristics that maintenance scheduling can not be determined for the unit output and in special cases need for load shedding, an optimization model of maintenance scheduling security correction is established based on the AC power flow model, considering the smooth constraints of upper and lower limit of unit output, load transfer and load shedding. And the objective function of the model is weighted sum of squares of load transfer and load shedding. In addition, considering of the discreteness of reactive power compensation of shunt capacitor and reactor and regulating transformer stalls, the discreteness constraints should be increased into the model. Both for continuous variables and discrete variables in the model, Semi-smooth Newton method is used to the first sub-problem of solving the continuous optimization. Based on the optimization results, keeping the continuous variables and discrete variables unchanged, and use immune genetic algorithms to solve the discrete optimization problem and continuous optimization problem alternately.The optimization method of global generation and transmission maintenance scheduling and security correction in this thesis have been verified by IEEE 30 standard systems and IEEE 14 standard systems, the simulation results proved that they are correct and effective.