Adjustable common mode choke coil is a commonly used inductor device, now more use of iron core and line combination method to adjust the inductance of the inductor, there are three commonly used methods.
1, saturated inductance method
Saturated inductance method requires the inductor on the core around the two windings: one is the working winding, alternating current; the other is the control winding, through the DC. By changing the size of the DC in the control winding to change the saturation of the core, thereby changing the size of the working winding inductance. The principle of saturation reactors and magnetic amplifiers is to adjust the inductance based on this approach.
2, switch control inductance method by common mode choke manufacturers
The switch control inductance requires that the inductor and the triac are connected in series and the inductance of the inductor is changed by turning on and off the triac. For example, in the application of sinusoidal energy divider AC regulated power supply.
3, orthogonal core control inductance method
Orthogonal core control inductance method is to rotate half of the C-shaped core 90 ¡ã and the other half of the butt, half of the core around the working winding, through the exchange; the other half of the core around the control winding, through the DC. The size of the work winding inductance is changed by changing the magnitude of the DC current in the control windings. For example, in switching power supplies, inverting power supplies, series compensators and phase shifters.
The disadvantage of using a variable inductor to change the inductance is a movable part and can only be adjusted manually.
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