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DC offset component in reference toshort circuit fault current
You need to provide more context to your questions. What is the application? What do you know so far? What the heck are you asking about?
When a short is applied to the secondary of an energized transformer, there may be a momentary DC current.
The polarity and the magnitude of the current depends on what part of the voltage cycle the short circuit occurred.
The magnitude also depends on the ratio of the transformer inductance and resistance and their values.
A very old standard to calculate the value of the DC current is
IEEE Std 462-1973, Page 29
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