On-line Optimization Of Urban High-voltage Power Network

With the development of urban modern power industry, power network configuration and mode of operation increased complexity, the various constraints of network is strengthening. In this case, to study the high-voltage power network for optimize the network and to ensure the supply reliability and the power quality, so as to ensure the power network safety and economic operation has a decisive significance for the development of national economy. How to continue improve and explore the convergence speed of model in practical urban high-voltage network and its optimization algorithm on the basis of research results, is one of the most important issues for the current power network research and the engineering practice.Network optimization is compared the performance indicators in the current operation mode and adjusted the network configuration by calculation, to determined the most reasonable way in the large number of possible operation. On-line network optimization method is based on the target parameters of total active power, total reactive power, total power loss, total reactive power loss, the number of switching operation, etc. as the safety economic indicators, to determine the optimal network in a time. After the calculation of safety economic indicators was completed, the system was given the current operating mode, as well as several post-optimized operation mode, or given the optimal network at any one time in the future, so that officers have been obtained a direction for the optimization of on-line network.In this thesis, a number of issues and practical algorithm for network optimization was researched. Network optimization is using mathematical optimization methods and modern heuristic methods. Mathematical optimization method is to make mathematical description for the optimal network, there are bound into the issue of extreme value, and then to solve the issue by optimization theory, the main method is use of the classical optimization techniques, such as linear optimization, nonlinear optimization, dynamic optimization, mixed-integer optimization. Modern heuristic method is a search algorithm that based on a natural mechanism such as natural selection, physical or biological phenomenon acts, it is fit for solve the combinatorial optimization problems, as well as nonlinear optimization problems that objective function or some constraints are non-differentiable, there are genetic algorithm, ant colony algorithm, Tabu search and particle swarm optimization, etc. For a variety of artificial intelligence methods, how to determine the correct search direction and improve the search efficiency of algorithms and obtain the global optimal solution are the key issues to improve the design of studies.In this thesis, based on the study of existing mathematical model and intelligent algorithm for high-voltage network optimization, the power network in Yuncheng City, Shanxi Province as an example, from the actual characteristics of the city high-voltage power network , the use of reduced-order enumeration method, combined with the sensitivity of indicators , according to the sensitivity of balance point active power to the admittance coefficient, the on-line calculation for the urban high-voltage power network was used to determine the best operation mode. With taking into account the constraints of run-time conditions, the optimal operation mode for urban high-voltage power network was determined at one time, the try of algorithm was completed on-line, the accuracy and the global optimum of the results was ensured.