The power demand of Kunming Power Grid accounts for nearly half of that of Yunnan Power Grid.As the load center of Yunnan Power Grid,it has to bear large traversing power in the electricity transmission from the west to the east,so the safe and reliable operation of Kunming Power Grid is of great significance to Yunnan Power Grid and the electricity transmission from the west to the east.N-1 check is conducted for the voltage of 110 kV and above of Kunming Power Grid through the Bonneville Power Administrat...