Direct-current converter

Claim 2

A direct-current converter comprising two direct-current input terminals, an oscillator circuit coupled to said input terminals and including amplifier means and a transformer having a primary winding connected thereto and a secondary winding, a rectifier circuit coupled to said secondary winding, a smoothing capacitor coupled to said rectifier circuit, two direct-current load output terminals coupled to the output of the rectifier circuit and to the capacitor, a saturable reactor having first anD second winding means, means connecting at least one first winding of the saturable reactor in a conductor between a terminal of the transformer secondary winding and a terminal of the smoothing capacitor, and means connecting a second winding of the saturable reactor between a terminal of the smoothing capacitor and a directcurrent output terminal so that the load current flows through said second winding thereby to saturate the reactor.

Claim 3

A direct-current converter as claimed in claim 1 wherein the windings of the saturable reactor are arranged so that the number of turns of said second winding exceeds the number of turns of said one first winding.

Claim 4

A direct-current converter as claimed in claim 2 further comprising means connecting a direct-current source to the direct-current input terminals and a load to the direct-current output terminals, and wherein the number of ampere turns of said second winding is so large under the influence of the load current therein that the reactor remains saturated for all desired values of load current.

Claim 5

A direct-current converter as claimed in claim 1 wherein said amplifier means includes first and second switching transistors energized from said input terminals and said transformer includes a feedback winding for supplying switching voltages to the control electrodes of the transistors.

Claim 6

A direct-current converter as claimed in claim 1 wherein said reactor first winding means includes a third winding connected between a terminal of the transformer secondary winding and said terminal of the capacitor.

Claim 7

A direct-current converter as claimed in claim 1 wherein said rectifier circuit comprises a full wave bridge rectifier with the capacitor connected across the bridge output terminals, the first reactor winding connected in series with the transformer secondary winding and the bridge input terminals, and the reactor second winding connected in series with the capacitor across the direct-current output terminals.

Claim 8

A DC converter comprising a pair of input terminals adapted to be connected to a source of DC current, an oscillator circuit energized from said input terminals and comprising a pair of switching transistors and a transformer having a primary winding coupled to the transistors, a secondary winding and a feedback winding coupled to the control electrodes of the transistors, a saturable reactor having first and second windings, a filter capacitor, a rectifier circuit, means serially connecting said first winding, said rectifier circuit and said filter capacitor across the transformer secondary winding whereby said capacitor is effectively isolated from the oscillator circuit by said first winding when DC power is first applied to said input terminals, a pair of DC output terminals for connection to a load, and means connecting said reactor second winding in series with the output terminals and the capacitor so that the DC load current flows in said second winding to saturate the reactor and effectively minimize the inductive impedance presented by said first winding.

Claim 9

A DC converter comprising a pair of input terminals adapted to be connected to a source of DC current, an oscillator circuit energized from said input terminals and comprising a pair of switching transistors and a transformer having a primary winding coupled to the transistors, a secondary winding and a feedback winding coupled to the control electrodes of the transistors, a saturable reactor having first and second windings, a filter capacitor, a rectifier circuit, means serially connecting said first winding, said rectifier circuit and said filter capacitor across the transformer secondary winding whereby said capacitor is effectively isolated from the oscillator circuit by said first winding when DC power is first applied to said input terminals, a pair of DC output terminals for connection to a load, and means connecting said reactor second winding in series with the output terminals and the capacitor so that the DC load current flows in said second winding to saturate the reactor and effectively minimize the inductive impedance presented by said first winding.

Claim 10

A DC converter as claimed in claim 7 wherein the reactor second winding has more turns than the reactor first winding.

Claim 11

A DC converter as claimed in claim 8 further comprising a third winding on the reactor serially connected with the rectifier circuit and the filter capacitor across the transformer secondary winding, said reactor second winding having more turns than the third winding.