System voltage sag performance estimation

Voltage sags are considered as the most important power quality problem for customers in Singapore. It can occur at any location in a power distribution system. Unfortunately, customers in all sectors such as residential, commercial and industrial have more sensitive loads compared to 10 years ago. As a result, customers with sensitive loads would like to find out the extent of voltage sags that their devices would be subjected to so that preventive or corrective measures can be planned. Unfortunately, there isn’t any readily available method for determining the system performance other than through long period of measurements over several years. A new analytical technique has recently being adapted from reliability analysis, and it has been proven to be successful in providing this estimation. This project, base on this analytical technique, constructs a sag density table to estimate the number of sag events that are expected to occur within a certain period. The Roy Billington Test System is used as the basic experiment system for this estimation. All types of symmetrical and unsymmetrical fault are considered/ with the help of this table, the voltage sag characteristics can be made known.Master of Science (Power Engineering