Analysis on cascading outages of Yunnan-Guangdong Ultra-high voltage transmission system

Many severe cases of black outs have taken place recently among different countries, which has been the significant factor on power systempsilas safe and stable operation. Taking 2010 Yunnan-Guangdong ultra-high voltage transmission system as example, power flow diversion is analyzed when faults occur on the sending Yunnan power system. Action of resistance three segment protection is obtained by comparing calculating resistance and protection setting, which provides the suggestion that how to prevent the cascading outage of Yunnan power grid. The research is constructive, and the conclusion has been applied on the manufacture of Yunnan power grid.