Power system stabilizer

A power system stabilizer provided at an individual power system which is to be separated (a separated system) due to an accident cutting off a link line which interconnects a plurality of individual power systems to form a large-scale power system (main system), said plurality of individual power systems including power stations such as power plants, transformer substations and loads, the power system stabilizer comprising:

• arithmetic processing means for assuming a total load-drop amount of the separated system caused by a voltage drop during said accident by an arithmetic operation based on a difference between a frequency in a representative power station belonging to said separated system and a frequency at a constant time after the frequency in said representative power station has exceeded a prescribed value;
• and
• control means for controlling a balance in demand and supply at each power station in said separated system on the basis of an assumption amount obtained by said operation of the arithmetic processing means.