Wide area measurement and protection system for emergency voltage stability control

When a major power system disturbance occurs, protection and control systems have to limit the impact, stop the degradation and restore the system to a normal state by appropriate remedial actions. Wide area measurement and protection systems limit the severity of disturbances by early recognition as well as proposition and execution of coordinated stabilizing actions. These systems complement classical protection and SCADA/EMS applications. This paper proposes a system design based on phasor measurement units, encouraging system protection schemes for frequency, small signal angle and voltage instability. The system is compared to classical protection and SCADA/EMS systems showing its benefits. A new algorithm for long-term voltage stability prediction is introduced using the proposed system setup.