Voltage sags mitigation on distribution utilities

Voltage sags are important to industrial reliability. Modern process contro ls are often sensitive fn volmgr sags. that may cause significant productio n outages. World-wide experience proves that a main origin of voltage sags affecting customers are short circuits on utility lines, with special refer ence to the overhead radial distribution ones. Since thr voltage sag during the fault is proportional to the short-circuit current, an effective fault -current limitation by means of a device connected at the beginning of the most exposed radial feeders will limit the expected voltage sag amplitude a nd improve the system power quality. In the paper a proposal for a simple b ur effective fault-current limiter is Riven and discussed.