Algorithm for relative location of voltage sags and capacitor switching transients based on voltage measurements only

This paper presents a new method for relative location of voltage sags and capacitor switching transients based on voltage measurements only. Voltage sags caused by network faults and transients caused by bank capacitor energizing are considered in this work. The algorithm automatically operates for assessing power quality, characterising and extracting information from voltage records obtained from power quality monitors (PQMs) in distribution systems. Positive sequence voltages are the descriptors used to determine the relative location of the voltage events. Instantaneous voltage changes are the descriptors used to determine the relative location of capacitor switching transients. Finally, proposed method is applied to a study case and it is verified that the method can be helpful to determine the relative location of the voltage events. MATLAB was used for validating this methodology, receiving voltage records from simulated voltage sags in ATP-EMTP and its easy implementation is verified.