On-line Optimization For The Configuration Of Urban High-voltage Power Network Based On Sensitivity Analysis

Loads and power sources are highly centralized in urban high-voltage power system, and power network has the characteristic with close-loop design and open-loop operation. The relative merits of urban power system structure directly influence the reliability and economy of power network, power network operation is adjusted to tap potentials, and then the network loss is reduced, and the extension to new network is slowed down. This network optimization is fit for the features of the present development-network.Recently, with the advanced research of routing protocol in network optimization, three kinds of optimization algorithm has been formed. The first kind is traditional mathematical optimization algorithm, the second kind is intelligent optimization algorithm, and the third kind is heuristic algorithm. With the mathematical foundation, the global search capability is materialized in the first algorithm, but relatively low to search for efficiency. In the second kind, biological principles are introduced into the network optimization algorithm, and the global optimum can be found out in great probability, but the running time is longer. With the Some heuristic rules, the third kind is of the higher retrieval efficiency, but the quality of search is little worse.A heuristic algorithm for the reliability problem of power system is given, and it is used in the on-line determination of the optimal operation. First, with the actual condition of the power network, the power network is preprocessed to reduce the number of branches in this algorithm, and the branches come from the loop network of power system. Second, taking economy and reliability as targets, the sensitivity for the total active power of load nodes and the active power of balance node to the coefficient of the branch active power is introduced respectively, and the degree of influences of power network topology and targets can be directly known from the values of sensitivity, and then the values of sensitivity are sorted respectively. With the sorts of sensitivity absolute values, the optimal operation of power network is determined in different objective functions at one time. With this algorithm, the contradiction between computation speed and precision in on-line optimization calculation is solved, and the physical concept is clear, and the programming is simple, and this algorithm is more suitable for on-line optimization of urban high-voltage power network. The practicability rapidity and effectiveness of the proposed mathematics model and algorithm have been validated in the IEEE 30-bus system.