SU1379907A1 - D.c. voltage converter - Google Patents

Abstract

The invention relates to the field of converter technology and can be used in the development of secondary power sources. The goal is K11D. The device allows forming a non-hazardous traAiectory of the operating point of transistors 3, 4 when two inverter cells are connected in parallel, which significantly reduces the current through the transistors. When transistor 4 is turned on, capacitor 7 is partially recharged by the reverse current of diode 6 from winding voltage 18. After this, capacitor 7 remains charged until the supply voltage during the turn-on period of transistor 4. At the moment when transistor 4 turns off, capacitor 7 is discharged to winding 18 , induces a voltage across the primary winding T1) of the unformer 2, and 1 Apr at the junction of the collector - emitter of transistor 4 is close to zero, which creates favorable conditions for turning it off. I il. /; // J / J "(L

Description

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The invention relates to electrical engineering and can be used in Secondary electrical systems for transforming and stabilizing a constant voltage.

The purpose of the invention is to increase Klljl.

The drawing shows a schematic diagram of the proposed Converter.

DC-DC converter 1 contains two inverter cells, each of which KOTOpi ix consists of transformers 1 and 2 and transistors 3 and 4, with the transformer and transistor connected in series and connected to the supply terminals. The correction circuit is produced on the first diodes 5 and 6, connected in series, and the capacitor 7, connected by one output to the junction point of diodes 3 and 6. The recuperator Hi.ic BTOpi ie the diodes H-1 1 are connected to the supply terminals. The third diodes 12 and 13 connect the output winding of the dump transformer 1 and 2 to the output filter, filter 14--16. Additional windings 17 and 18 include a follower along with diodes B and 9 or 1 (J and 11, and inter-co6oi i windings are connected via an additional diode and according to the first diodes i li 6 correction lepi. Capacitors 19 and 20 are connected in parallel) } 1st windings of transformers 1 Il. 1) Lok -1 control of the sub circuit with dppen output to pepp control transistors) and 4.

The mapper works in the following way.

When you turn on the transistor 3 trans boat format. The power supply is connected to the power source, and Mou (iiocTb is transferred to the load. When the transistor 3 is locked (when: this1 the transistor 4 is also closed), the voltage on the windings of the transformer 1 changes polarity and the capacitor 7 is charged by the voltage of the winding 17 through diode 5. After the pause ends, transistor 4 is turned on. At this point, the voltage on winding 18 (and on the primary winding) has the same value as on capacitor 7. Therefore, the voltage at the collector-emitter junction is equal to the voltage difference of the power supply and on the primary winding, i.e. close to zero. When transistor 4 is turned on, capacitor 7 is partially charged by the reverse current of diode 6 to

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The power supply voltage in the switch-on interval of the transistor 4. At the time of the transistor turning off, the capacitor 7 is discharged to the winding 18, induces a voltage on the primary winding of the transformer 2, and the voltage on the junction collector emitter of the transistor 4 at close to zero.

When transistor 4 is turned on, the capacitor 7 is partially recharged by the reverse current of diode 6 from the voltage of the winding 18. After this, the capacitor 7 remains charged until the supply voltage during the turn-on period of the transistor 4. At the moment the transistor turns off, the capacitor 7 is discharged to the winding 18, induces the voltage on the primary winding of the transformer 2, and the collector junction voltage of the transistor 4 is close to zero, which creates favorable conditions for turning on the transistor 4. After turning off the voltage on the winding 18 and Changes the polarity and recharges the capacitor 7 through diode 6. At the moment of turning on transistor 3, the voltage on the primary winding of transformer 1 is equal to the voltage of the power supply and is directed oppositely, which ensures the zero voltage on the transistor 3 and favorable conditions for its switching on . Further, the processes are repeated.

Diodes 8-11 serve to return reactive energy to the power source. Capacitors 19 and 20 serve as ddt for quenching a voltage peak on transformers during the switching off of the transistors, due to the fact that when the turning off of the transistors 3 or 4, the primary winding energy cannot instantly be transferred to the additional winding 17 or 18. The better the connection between the windings, the smaller than the capacitors 19 and 20. Therefore, the capacitors receive the energy of the inductance at the moment when the transistors 3 or 4 turn off.

In the proposed circuit, the voltage across the transformers is twice as large as in the circuit of the known converter, which reduces the amount of current through the transistors and increases the efficiency.

Claims (1)

Claims A DC / DC converter containing two single-phase inverter cells, each of which is made on a transistor and a transformer connected in series, a correction circuit consisting of two first diodes connected in series with a main capacitor connected by one input to a common connection point of the first diodes, two second diodes and a control unit, the output winding of each transformer through the third diodes connected to the output filter, characterized in that Efficiency enhancement, additionally introduced one additional winding on each transformer, two fourth diodes and two additional capacitors, let's take the primary windings of transformers shunted by additional capacitors and are located to one input terminal and transistors to another input terminal, every second diode, additional transformer winding and every fourth diode are connected in series and connected between the input terminals, additional windings of transformers are connected sequentially and according to the first diodes of the correction circuit, and the main capacitor is connected to the common junction by the second pin itelnyh transformer windings.