Q8Electrical Energy Conversion And Auditing
Question
Q.8. What are the issues of power quality?
Answer
Power quality issues include voltage sags/swells, harmonics, flicker, voltage unbalance, and transients, all of which can cause equipment malfunction, increased losses, and reduced equipment life.
Power quality issues include voltage sags and swells (brief reductions or increases in voltage, often caused by faults or large load switching), harmonics (distortion of the pure sinusoidal waveform caused by non-linear loads such as variable-frequency drives and electronic ballasts, which increase losses and can cause equipment overheating), voltage flicker (rapid, repetitive voltage fluctuations, often caused by arc furnaces or other rapidly-varying loads, perceptible as visible lighting flicker), voltage unbalance (unequal voltage magnitudes across the three phases, which causes excessive heating in three-phase motors), and transients/surges (very brief, high-magnitude voltage spikes, often caused by lightning or switching operations) — all of which can degrade equipment performance, cause nuisance tripping, increase energy losses, and shorten the operating life of connected electrical equipment.