Research On Emergency Control Following Splitting Accident In Wanzhou Power Network

As the development of the power system, the enlargement of the power network scale and the increase in transmission distance, the decentralization of voltage become more severely. Together with the intensive fluctuation of load, the reactive power change greatly through the power network. Large disturbances are easy to lead voltage collapse under such circumstances.There were many power system collapses happened as a result of voltage instability in the end of twentieth century, which cause blackout for a long time through out large areas. Extensive concern is brought to this issue around electric power engineering and academic circles .Attentions are alternated to the definitions of voltage stability, mathematical model, analysis methods, voltage stability index, the mechanism of voltage collapse as well as the investigation into the schemes to prevent voltage collapse. But from the whole situation, the research on the voltage stability is not as extensive and deeply as the issue of rotor angle stability.As the development of the 500kV transmission network, large amount of reactive power inject into the regional power network closely interconnect to the higher voltage power network. While the transmission power fluctuate in great magnitudes, the reactive power inject into the regional power network fluctuate greatly at the same time, consequently the voltage stability is threatened intensively.Jun.23,2000 following the Wanzhou power network splitting from the main power network of chongqing, that disintegration accident happened in Wanzhou due to voltage collapse is such a case.As an example of " 6.23 accident", the paper make a research on the regional power network voltage stability. The paper makes a research on the mechanism and cause that lead to the voltage collapse, and then put forward the schemes to prevent regional power network voltage collapse.Combined with the facts of Wanzhou power network, the main analysis and research in this paper are as follows:â‘  The fundamental concept of voltage stability .â‘¡ The main components reactive power-voltage characteristic and the operation characteristic of the modern reactive power/voltage control equipment.â‘¢ Accurate mathematical model is established. Dynamic numeric simulation isused to analyze Wanzhou 110kV power network voltage stabilityâ‘£Put forward the practical measures to enhance Wanzhou power network voltage stability and illustrate the necessary to apply modern reactive power-voltage control equipments.The research in this paper is significant in theory ,having practical engineering value in improving Wanzhou power network voltage stability ,on the other hand the outgrowth should be extended to analyze other similar regional power network.