Research About Performance Of Operation Mode Based Node Reactance Matrix

The scale of interconnected power system is expanding, the gradual strengthening of ties in power grids has brought huge benefits, while also making complexity. In particular, the power system short-circuit levels are increased annually, it tests the performance of equipment during power failure and also restrict the development of power grid, so how to balance the power grid between running mode and fault mode is particularly important.The measures of short-circuit current limitation can be divided into two basic ways, one is changes in operation mode, the other is changes in facilities. Since the power system is a large man-made system, reasonable grid design and determination of reasonable operation mode in order to avoid equipment upgrades should be the prerequisite. However, the performance of dynamic effects and thermal effects which reflected by the short-circuit current size of the grid is only one of two basic properties of operation mode, the performance of the normal operation which reflected by the balance between power generation and electricity in safe economy status simultaneously with it, and both contradiction between them. Only considering the short-circuit performance without comprehensive considering the performance of the normal operation is one-sided with great limitations. Grid operation mode should be a compromise decision-making, especially those related to short-circuit current limited circumstances, there should be a wide range of grid operation mode decision-making, and thus gives a moderate operation mode.This thesis brings switch variables into the decision-making capacity, it has a in-depth discuss about the relation between Performance of the power grid and switch status, the thesis analyzes the dialectical relationship between short circuit current and the DC power flow and node reactance matrix change under different operation modes. On the basis of Mechanism Analysis of node reactance matrix, it proposes the indicators about performance of operation mode. With a simple example of analysis of grid, it indicates that the indicator have an effective role, and as indicators basis, an attempt to use genetic algorithms to find the best operating mode under corresponding performance requirements of the power grid.This thesis makes detailed analysis about the performance of 2010 Shandong Power Grid operation mode, pointing out that the main problems of this operation mode is the short-circuit current exceeding. The analysis of multi-running mode of Shandong Power Grid about the indicators and performance based on the application of short-circuit current limitation with the Shandong Power Grid show that the indicators have a good validity. Thus, in the decision-making of Shandong power grid operation mode, it should be feasible to run an integrated way taking into account overall performance, conduct extensive research and analysis, find the best operating mode with good balance between short-circuit current level and the performance of normal operation of the grid.