Magnetic measurement and analysis of c-type amorphous by an improved adjustable air gap tester

A novel magnetic properties tester is designed to accurately and conveniently change the air gap of the core, which can fix cores of various types. The dynamic magnetic characteristics of the amorphous core under sinusoidal excitation within 20 kHz is measured with different air gap lengths and magnetic flux density. It is found that in the case of the small air gap, the total loss decreases as the air gap increases. When the frequency is 20 kHz and the flux density is 0.1 T, the loss can even be reduced by 7%. This paper analyzes the experimental data and summarizes the influence of the air gap and magnetic flux density about the core loss. Besides, the influence of air gap on magnetic flux density distribution is illustrated and analyzed by the means of FEM (Finite Element Method). It is valuable for the design of high frequency transformer and inductor.