Date of Graduation


Document Type


Degree Name

Bachelor of Science in Electrical Engineering

Degree Level



Electrical Engineering


Ang, Simon S


The purpose of this thesis is to present research on magnetic amplifiers and to discuss how magnetic amplifiers are useful in voltage regulation applications. Beginning with a background in magnetics and magnetic properties, this thesis outlines the importance of the B-H curve and explains how to simulate the B-H curve of a saturable inductor using LtSpice. Furthermore, two saturable inductors can be aligned in antiparallel to create a magnetic amplifier. The theory of magnetic amplifiers is dated, but its simplistic design has benefits for modern applications. The magnetic amplifier acts as a variable impedance switch where a small amount of DC current can control the output voltage of a circuit. This is possible because the control current varies the core’s position on its B-H curve. Once the core is saturated, any further increase in control current will not affect the output voltage of the circuit. Based on the design of the magnetic cores the saturation point can be adjusted. Using the saturable inductor model in LtSpice, a magnetic amplifier can be simulated in a voltage regulation circuit. This circuit is constructed and tested using three different types of magnetic materials for the magnetic amplifier. The correlation between the simulated and measured results attests to the importance of modeling circuits before construction. This design method ensures reproducibility and this thesis shows the effectiveness of magnetic amplifiers in achieving voltage regulation.