Working principle of current transformer in operation

- Jan 11, 2021-

The current transformer turns the large current on the primary side into a standard small current (5A or 1A) on the secondary side. The working principle is similar to that of an ordinary transformer, and it works according to the principle of electromagnetic induction. Compared with the load on the secondary side, the primary internal resistance of the current transformer is very large, which can be regarded as a current source with infinite internal resistance. When the current transformer is working normally, the magnetic flux density is very low, and the short-circuit current on the primary side becomes very large when the current transformer is short-circuited, which greatly increases the magnetic flux density, and sometimes even far exceeds the saturation value.