Introduction to magnetic amplifier

●Definition

A magnetic amplifier is an electrical appliance that uses a ferromagnetic material with nonlinear characteristics to make an iron core and magnetizes it with DC and AC currents for power conversion. Magnetic amplifiers are mainly used in electrical automatic control systems, such as motor speed regulation, voltage regulation, etc.

●Core composition

The magnetic amplifier can accurately control the switching power supply, thereby improving its stability. Magnetic amplifier cores can be made of permalloy, ferrite, or amorphous or nanocrystalline (also known as ultra-microcrystalline) materials.

●Core advantages

Amorphous and nanocrystalline soft magnetic materials have high magnetic permeability, high squareness ratio and ideal high temperature stability. When used in magnetic amplifiers, they can provide unparalleled output adjustment accuracy and achieve higher working efficiency. , So it is very popular. In addition to the above characteristics, amorphous and nanocrystalline magnetic cores also have the following advantages:

1) Low saturation permeability; 2) Low coercivity; 3) Small recovery current; 4) Low core loss;

●Working characteristics

Current amplification factor=Magnetic amplifier output current/input current; Power amplification factor=output load power/input control power. The output current of a simple magnetic amplifier has nothing to do with the polarity of the input current. When the input control current is zero, the output current is not equal to zero, but there is a no-load current lo.