DC-TO-AC VOLTAGE CONVERTER Russian patent published in 2005 - IPC

FIELD: converter engineering; power supplies.

SUBSTANCE: proposed converter has two p-n-p transistors 1, 2 and two n-p-n ones 3, 4, all four transistors being interconnected in bridge circuit. Emitters of transistors 1 and 2 are interconnected and connected to one pole of power supply 5; emitters of transistors 3 and 4 are also interconnected and connected to other pole of power supply 5. Collectors of transistors 1 and 3 are connected to terminal A of primary winding AX of transformer 6 (shown in dash lines) and other terminal X of this winding is connected to common connection point of collectors of transistors 2 and 4. One of secondary windings of transformer 6, for instance a₁x₁, is connected through capacitor 7 between bases of transistors 3 and 4 whose emitters are directly interconnected, and load 8 is connected to secondary winding a₂x₂ of transformer 6. Resistor 9 is connected between bases of transistors 1 and 4, resistor 10, between bases of transistors 2 and 3. Circuit set up of diode 11 and resistor 12 is inserted between emitter and base of transistor 3 and similar circuit of resistor 13 and diode 14, between emitter and base of transistor 4. Feedback circuit set up of secondary winding a₁x₁ of transformer 6 and capacitor 7 can be also inserted between bases of other pair of transistors 1 and 2 whose emitters are also directly interconnected, that is it can be transferred from base circuit of transistors 3 and 4. In this case circuit set up of diode 11 and resistor 12, like that of diode 14 and resistor 13, will be, respectively, connected to emitter-base junction of transistors 1 and 2. Proposed design makes it possible to use both unsaturable and saturable transformers with primary winding not center-tapped.

EFFECT: reduced voltage across transistor collectors and reduced number of base windings.

1 cl, 2 dwg