Differential flow anomaly
Thread Content
When starting the high-voltage soft starter, why is there an abnormal differential current alarm for the main transformer on the corresponding side?
When a high-voltage soft starter starts up, high-order harmonics are generated. Due to the differences in the volt-ampere characteristics of the protection windings of the current transformers on the high-voltage and low-voltage sides of the main transformer, it is normal for a differential current overload alarm to occur; this will not cause the differential protection of the main transformer to trip. If there are concerns, the main transformer differential current over-limit alarm setting can be modified.