Study Of Analysis And Control To Central China Region Power Grid's Low Frequency Oscillation

This dissertation combines the engineering needs of the Central China Grid and the scientific research subject is accomplished. In order to effectively use the power resource and realize the strategy objective of "west-east electricity transmission", so that promotes the networking in whole nation. At present, the State Grid corporation of China has fully used the sending power project of two-beach power stations which is running and the three gorges transmitting and transforming electricity project which is being build and has built the temporal channel of "Sichuan-east electricity transmission". Because the transmitting electric power of Sichuan electricity to Central China Grid is long, belonging to the AC weak link of big electrical network, can lead to the stabilizing problem extremely outstand that electrical wire of Central China Grid and Sichuan-chongqing Grid 500KV, also has the possibility of low frequency oscillation.This dissertation has clear studying objective and the real application meaning is big, and has many studied contents, and the knowledge point and area, which involves is wide, and possesses a lot of systematic research value. According to the real circumstances and the subject item requirement of electrical network, this paper has gone into deep and systemic research.According to the concrete circumstances of the two grids, this dissertation has expounded possibility that occurs the low frequency oscillation and has done the related calculation, and briefing restrains the measure of low frequency oscillation has been put forward.The dissertation has seven chapters. In chapter 1, we introduce the purpose and meaning of this subject study and has simple introduced the harm of the low frequency oscillation and the necessity and importance to research; in chapter 2,we introduce the general situation of Central China Grid and Sichuan-chongqing Grid and analyses the problem that the network self existing at present; in chapter 3, we mainly carry on the mechanism analysis to the low frequency oscillation, and have given out the mathematical models which carry on the calculation of trend and the low frequency oscillation; in chapter 4,we introduce low frequency oscillation examples that occurred once and carrythough the trend counts and transient state stable counts and the stability can be analyzed after the system is disturbed; in chapter 5,we have carried on the low frequency oscillation counts and analyzes behind the two linked nets and find out the locations that probably giving rise to the low frequency oscillation; 6, we brief introduce the restraining scheme to the low frequency oscillation and the restraining measure based on the power electronic device; in chapter 7,we conclude the work of the paper and prospect the future and the train of thought studied further.