On the Control of Magnetic Amplifiers for High-Frequency DC-to-DC Converter

The control characteristics of the half-wave magnetic amplifier as a pulsewidth modulator for the high-frequency dc-to-dc converter are discussed. The control region of the magnetic amplifier is analyzed by the examination of the dc magnetizing characteristics of the core and the reverse recovery of the diode in the converter circuit. As a result, a dead angle of the pulsewidth modulator due to the reverse recovery is derived analytically as a function of the switching frequency. A control method to reduce the dead angle is proposed so that a wider regulation range may be obtained in high-frequency switching.