RESET CURRENT DRIVE CIRCUIT OF MAGNETIC AMPLIFIER AND SWITCHING POWER SUPPLY CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a reset current drive circuit of a magnetic amplifier, capable of preventing a constant-voltage control range from narrowing by a current, other than a reset current from a reset current supply circuit.;SOLUTION: This reset current drive circuit of the magnetic amplifier includes a rectified output circuit part, for forming a predetermined DC voltage from the output of the magnetic amplifier consisting of a saturable reactor, through which an output current flows, when a pulse voltage is applied and a core is in a saturated condition, and the reset current supply circuit part for controlling the reset current which flows through the saturable reactor, based on a DC voltage value of the rectified output circuit part. A switching device is connected, between an output terminal of the magnetic amplifier and the predetermined voltage supply. A reset current improving circuit is provided, of which the switching device is turned on so as to flow via the switching device, without flowing through the saturable reactor, and the current other than the reset current from at least the reset current supply circuit part, immediately after the voltage applied to an input terminal of the magnetic amplifier, is inverted to negative side.;COPYRIGHT: (C)2004,JPO