Why insert an air gap in the iron core magnetic circuit

- Sep 04, 2020-

When the inductance device has DC magnetization, the magnetic permeability of the iron core will drop rapidly. When an air gap is inserted in the magnetic circuit, due to the large magnetic resistance of the gap, the mass magnetic potential generated by the DC current is mostly on the air gap, which greatly reduces the DC magnetic potential in the iron core, and the magnetic permeability of the iron core rise.

After the air gap is opened, the magnetic permeability of the iron core increases, but the effective magnetic permeability decreases with the increase of the gap, but the general trend is that the effective magnetic permeability of the iron core with the air gap is higher than the effective magnetic permeability without the gap. The effective permeability can reach the maximum under a certain air gap length.


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