By Topic

Intermittent Line-to-Ground Faults in Generator Stator Windings and Consequences on Neutral Grounding

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Braun, D. ; ABB Switzerland, Zurich, Switzerland ; Koeppl, G.S.

Line-to-ground faults in the stator windings of unit generators have been simulated on the basis of test results obtained on medium-voltage cables in systems with isolated neutral. Those tests have shown that single-phase faults in insulating materials, such as polyethylene or comparable synthetics, are normally arcing faults and the arcing channel in the insulating material behaves like a restriking switch which is able to interrupt transient fault currents at current zero; however, it restrikes at a certain voltage level due to damaged insulation and small distances between the phase conductor and ground. Similar behavior may be assumed for generator stator windings. The simulations show that for such a fault pattern, resonant grounding is distinctly to be preferred to high resistance grounding. The corresponding standards do not reflect transient and intermittent fault currents in stator windings and, therefore, assess both grounding methods as nearly equivalent.

Published in:

Power Delivery, IEEE Transactions on  (Volume:25 ,  Issue: 2 )