Voltage flicker is one of the most common power quality complaints reported by utility customers. The term flicker refers to visible changes in lighting intensity caused by rapid fluctuations in…
Visualizing Loose Neutrals with RMS Capture Graphs
Loose neutrals represent one of the most hazardous and subtle single-phase service issues encountered by utility power quality (PQ) engineers. The condition arises when the neutral conductor connecting the center…
Voltage Tug-of-War The Silent VFD Killer
The modern variable-speed drive (VFD) is a sophisticated power electronic system, yet the front end is still a deceptively simple six-pulse diode bridge. That simplicity means the rectifier has little…
Riding Through Voltage Sags with the IEEE 1668 Standard
Voltage sags are the most common power quality issue, and also the most costly for industrial power users. It's not practical for a utility to eliminate all sags, so industrial…