Power grid operation mode optimizing method for controlling short circuit current level

Abstract

The invention discloses a power grid operation mode optimizing method for controlling a short circuit current level. The method is characterized by comprising the following steps of 1) determining a candidate disconnection branch set S, and 2) establishing a disconnection combination optimization model based on a node voltage method. According to the invention, the model established based on the node voltage method is a mixed integer linear programming model and can be solved by calling a CPLEX optimizer; an optimal disconnection strategy can be quickly determined by virtue of the powerful computing capacity of the CPLEX optimizer. Finally, simulation verification is performed on the validation of the model by taking an IEEE39 (Institute of Electrical and Electronics Engineers 39) node system and Zhejiang Power Grid as examples.

Description

technical field [0001] The invention relates to the field of power systems, in particular to a grid operation method of the power system, in particular to a grid operation mode optimization method for controlling short-circuit current levels. Background technique [0002] With the sustained and rapid development of the national economy, the load of the power system continues to increase. In order to ensure the safety and reliability of power supply, the power grid structure is gradually strengthened, and power supply projects continue to be invested. The increasing number of ring networks in the gradually strengthened power grid structure shortens the electrical distance between substations, thereby increasing the level of short-circuit current; the increase in load requires continuous investment in power supply projects, and comprehensive consideration is given to the shortage of construction land for power plants and the effective use of energy. On the one hand, there has ...

AI Technical Summary

Problems solved by technology

However, the latter two are subject to technical limitations, and the investment is high, which will also have a greater impact on relay protection; and for the same branch, the current limiting effect of branch circuit breaking is the best, and the operation is convenient , low cost, should be given priority

However, the disconnection of the line may lead to a decrease in the reliability level of the power grid, and an unreasonable line disconnection scheme may even destroy the connectivity of the grid. Therefore, the number of disconnected lines should be minimized to maintain the integrity of the grid

At the same time, there are often multiple sites with excessive short-circuit current in the power grid, and it is not easy to find an optimal disconnection strategy that comprehensively considers the current limiting effect of each site

Document 1 "Grid adjustment optimization algorithm for limiting short-circuit current of 500kV power grid [J]" (Zhang Yongkang, Cai Zexiang, Li Aimin, etc., Automation of Electric Power Systems, 2009, 33(22):34-39) uses the self-impedance sensitivity coefficient to determine the effect of current limiting Evaluation can find the combination of broken lines that break less lines and effectively control the level of short-circuit current, but the use of implicit enumeration method requires a large amount of calculation and the optimality of the solution is difficult to be effectively guaranteed, and the scope of application is limited

Document 2 "Transmission network reconfiguration algorithm considering short-circuit curtailment and voltage stability index [C]" (Kumpee Boonsuwan, Naebboon Hoonchareon. The 8 th Electrical Engineering / Electronics, Computer, Telecommunications, and Information Technology (ECTI) Association of Thailand–Conference, 2011: 877-880) uses rapid voltage stability indicators as the basis for the selection of several feasible measures, and also uses enumeration algorithms. The strategy given depends heavily on the experience of the operator

Images