Analysis On Transient Voltage Stability In The Receiver Power Area At High Proportion After The Splitting Of Power Grid

There have been many voltage instability accidents that happened to the local Power systems and the state Power system within the last few years.The electricity consumption of lots of receiver system that power supply is insufficient grows rapidly. Therefore, power required is transmitted by long distance lines from sending system and proportion of reception power in the receiver system increases continuously. Lack of reactive power support capability of the power system itself lead to voltage instability problems which bring a great deal of potential risks to the safe operation of the power system have drawn much attention of researchers. The mechanism of voltage instability, voltage instability criteria, voltage stability research methods and measures to prevent voltage instability and other issues is becoming a hot topic.This article builds a data platform with the help of the power system simulation software PSD – BPA based on some a receiver power grid in Hunan Province and studies the voltage stability in the receiver power area after the splitting of power grid. The main content of this paper includes the followings.1. This thesis firstly summarizes and analyzes of the background and significance, classify and the analysis method development of voltage stabilization study. Then the static and dynamic voltage instability mechanisms are preliminary discussed. Based on the simple system, this paper studies the instability mechanisms of pure resistance circuit and AC circuit respectively.2. With the transient voltage stability mechanism of receiver power system as the study object, this thesis respectively discusses the impacts on it of dynamic reactive power support, the static voltage stability margin and load characteristic. The simulation researches the voltage stability characteristics under the receiver power system has different levels of reactive power supports and different voltage stability margins. Aiming at the impact of load characteristic on voltage stability, the corresponding simulation model is built to compute and analyze the influences of static and dynamic characteristics of load on voltage stabilization separately.3. A certain receiver power system becomes island because the transmission line between it and main power grid is in trip due to accidents. It is generally acknowledged that after the splitting of power grid the frequency of the islanded grid will decline. But the actual operating experience indicates that the voltage will drop but the frequency won’t drop and even increases. Build a system and make simulation analysis based on data of a certain receiver power system in Hunan power grid by software PSD-BPA. This article discusses the voltage instability process and its factors in the receiver power area at high proportion after the splitting of power grid. Through the simulation of typical example, the impacts of dynamic reactive power support, load characteristic, fault type which leads to splitting, etc. on voltage condition of island is analyzed. Conclusion of this research is available for reference to emergency control method of island voltage after the splitting of power grid.