Abstract

A power supply including a saturable reactor voltage regulator using a core formed of relatively inexpensive magnetically soft material with a B-H loop which is poor in squareness. The reset point of the saturable reactor core is established by a clamping circuit, including a transistor switch and diode in series, which effectively clamps a short circuit across the reactor winding when the core reaches a desired reset point on its B-H loop. The proper time of actuation of the clamping circuit is selected by a control circuit which includes a comparator for generating a control signal for actuating the switch whenever an error voltage derived from the output voltage exceeds the voltage level of a triangular wave developed by integrating a replica of the input pulsations to the magnetic amplifier structure. The saturable reactor is driven to saturation at a time during positive pulsations related to the position of the reset point.In one embodiment, the clamping circuit is connected directly across the reactor winding, while in a second embodiment, the clamping circuit is connected across a secondary reactor winding. A bias winding for the reactor may be provided to shift the B-H loop of the core to the right to increase the range of adjustment.