By analyzing the coordination between preventive control and blocking control of cascading failures

a coordinated control model based on risk assessment is proposed for power system cascading failures in terms of reducing the risk of blackout. First

the risk of cascading failure is solved by considering the failure of lines

power flow transfer

hidden failures

and weather factors. Then the coordinated control model is expressed as an optimization problem based on risk indices. Besides

the coordinated control model also considers the position of blocking control

which is confirmed by the risk importance of faults. Finally

the example analysis shows that the model can effectively coordinate the preventive control and the blocking control and provide the control scheme with the highest cost performance under different weather conditions. Compared with the pure preventive control and blocking control

the scheme is able to meet the demand of security and economy

while provide a reference for decision-making of defense. This work is supported by State Grid Corporation of China

Major Projects on Planning and Operation Control of Large Scale Grid (No. SGCC-MPLG024-2012)

Specialized Research Fund for the Doctoral Program of Hefei University of Technology (No. 2012HGBZ0657)and Anhui Provincial Natural Science Foundation of China (No. 1408085ME100).