Examples of Voltage Stability Analysis

Abstract

Big power grid operation as the sign of modern power industry brings self-evident economic effect. However, any accident may cause serious consequences. Therefore, safe operation of the big power grid is an important research subject for electric power workers both at home and abroad. Several typical voltage collapse accidents abroad are the profound warning for us in development of our power grid. In accordance with characteristics of interconnected power grid in China, the power grid structure becomes more and more complicated. There are more and more AC power transmission channels, or AC and DC power transmission channels in parallel for transmitting power intensively across different areas in long distances. The difference between peak and valley loads is enlarged with extensive application of new power transmission technology. Therefore, it is more and more difficult to regulate and control voltage; in some interconnected power grids, the risk probability of voltage collapse accident increases owing to coexistence of insufficient dynamic and reactive standby at center of the end load.