Before and during voltage sags
2005 (English)In: IEEE Industry Applications Magazine, ISSN 1077-2618, Vol. 11, no 2, 39-46 p.Article in journal (Refereed) Published
Voltage sag is a momentary decrease (10-90%) in the root-mean-square (rms) voltage magnitude for duration from a half cycle (10 ms in a grid where f=50 Hz) to 1 min. Voltage interruptions are deeper voltage sags whereas transients are shorter than 10 ms. Generally, deeper voltage sags cause higher current peaks and larger torque peaks. The peak current after a voltage sag depends on both the voltage sag magnitude and the voltage magnitude before the voltage sag. Thus, a voltage sag to 90% may cause higher peak currents than a voltage sag to 80% for the same synchronous machine. If the machine is capable of handling the highest current peaks and torque peaks, the protection equipment should only measure the voltage sag magnitude and duration and, from that, use the synchronism curve to determine when to shut the synchronous machine down.
Place, publisher, year, edition, pages
2005. Vol. 11, no 2, 39-46 p.
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-37714DOI: 10.1109/MIA.2005.1405825ISI: 000227072800004ScopusID: 2-s2.0-14844334969OAI: oai:DiVA.org:kth-37714DiVA: diva2:434942