Voltage sags observation through optimal monitor locations

The concern towards voltage sag has increased rapidly due to the amount of losses it created. Throughout the world, many researchers have proposed a study on the characteristics and the mitigation methods which may be used to overcome or reduce the effect cause by the voltage sag. In this paper, a method that used a minimum number of power quality monitors has been proposed to monitor the occurrence of voltage sags in the utility system. By using the area of vulnerability concept, the optimal monitor locations with zero blind spot area can be determined. The proposed method also used the concept of monitor redundancy to ensure the correctness of the monitor reading, validation purposes and to ensure the reliability of the monitoring system is 100%. The proposed method has been tested with two standards system; IEEE 30-bus system and IEEE 300-bus system and the results then is compared with other monitoring method.