Transformer Testing & Maintenance
Power Transformer Failures
Insulation Resistance Test
Transformer Testing & Maintenance
How to Improve Transformer Protection
Using symmetrical components for fault discrimination in differential protection
BY IMRAN RIZVI, ABB Inc.
Classical differential protection schemes are subject to ghost differential currents due to current transformer (CT) saturation and magnetization currents. Several methods are used to counter the impact of these unwanted differential currents. Electricity Today Magazine and ABB will focus on how to improve transformer protection by using the symmetrical component techniques to stabilize differential protection schemes without sacrificing the speed and...
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