RU2278460C2 - Non-symmetrical transformer of direct voltage to direct voltage - Google Patents

Abstract

FIELD: electric engineering, possible use as transformer of direct voltage to direct voltage for engineering of various secondary electric power sources.

SUBSTANCE: transformer contains transformer, electronic keys, connected to primary winding of transformer and to output capacitor, while secondary winding is connected to diodes and through inductance to output capacitor. Device also contains additional diode and commutating transistor element. Secondary winding of transformer is provided with additional portion, which through additional diode is connected to electronic key.

EFFECT: increased reliability while maintaining efficiency of transformer.

2 dwg

Description

The invention relates to the field of electrical engineering and can be used as a DC to DC converter when developing various sources of secondary power supply.

A known converter in which the conversion of direct voltage to alternating voltage is carried out using a bridge converter of alternating voltage to constant with further conversion of direct voltage to constant of the required parameters (RF patent No. 2006161, CL N 02 M 7/04 from 05/28/94).

The disadvantage of this device is that it contains many elements, causing a relatively low reliability of this Converter.

So, the presence of the main and additional inverters, a control unit for them and electronic keys according to the selected control law, although it improves the dynamic characteristics of the converter, the reliability remains relatively low.

The closest technical solution for the combination of essential features is a DC-DC to DC converter, described in US patent No. 5754413, class. MKI N 02 M 3/22 dated 05/19/1998

This converter contains transformers, electronic keys connected to the input capacitor and the primary winding of one of the transformers, the secondary winding of which is connected to the diodes and through the inductance to the output capacitor.

The disadvantage of this converter is that it has insufficient reliability due to the fact that during operation there is a high reverse voltage on the diode connected to the inductance and the output capacitor. Although the presence of two transformers reduces the reverse voltage at the diode, however, overcurrents also occur at low voltage values at the output capacitor.

The problem to which the claimed invention is directed, is to increase reliability while maintaining the efficiency of the converter.

The problem is solved due to the fact that the asymmetrical DC-DC converter containing a transformer, two series-connected electronic keys connected to the primary winding of the transformer and the input capacitor, and the secondary winding is connected to the diodes and through the inductance with the output capacitor, is equipped with additional diode and an electronic key, and the secondary winding of the transformer is equipped with an additional section, while the end of the additional section of the secondary winding h Res additional diode is connected to an additional electronic switch, the cathode of which is connected to the cathodes of diodes.

Figure 1 presents a schematic diagram of an asymmetric DC-DC to DC converter. Figure 2 - output characteristic of the Converter. The converter contains a transformer 1 with a primary winding 2 and a secondary winding 3 with an additional section 4, electronic keys 5 and 6, diodes 7, 8 and 9. One end of the winding 2 is connected to the input capacitor 10, and the other end to a common point of the electronic keys 5 and 6. The main section 3 of the secondary winding is connected to the anodes of the diodes 7 and 8, the cathodes of which are connected through the inductance 11 to the output capacitor 12. The end of the additional section 4 of the secondary winding is connected to the anode of the additional diode 9, the cathode of which is connected to the additional ele a cathode key 13, the cathode of which is connected to the cathodes of the diodes 7 and 8.

The device operates as follows.

Electronic keys alternately turn on with a high frequency. At the initial moment, when the output capacitor 12 is discharged, the electronic switch 5 opens and the inductance current 11 increases along the circuit: 3-7-11-12-3, and when locked, it drops along the circuit: 11-12-8-11. At the same time, when the key 5 is locked, the key 6 is opened and the energy stored in the dissipation inductance of the primary winding 2 of the transformer 1 is recovered in the input capacitor 10, which leads to the demagnetization of the transformer.

When the voltage at the output capacitor of a certain value corresponding to the transformation coefficient of the windings 2 and 3 is reached, an additional electronic switch 13 is opened and the output capacitor is charged through the circuit: 12-3-4-9-13-11-12 with the key 5 on.

Due to the fact that the converter is made with a changing transformation coefficient, it is possible to reduce the overcurrents flowing through the diode 8 at the beginning of charging the output capacitor and in the current limiting mode at low voltage values of the output capacitor (Fig. 2).

Thus, the presence of additional diode and electronic key can improve the reliability of the converter while maintaining a high value of the efficiency of the converter.

Claims (1)

An asymmetrical DC-DC converter containing a transformer, two series-connected electronic keys connected to the primary winding of the transformer and to the output capacitor, and the secondary winding is connected to the diodes and through the inductance to the output capacitor, characterized in that it is equipped with an additional diode and an electronic key and the secondary winding of the transformer is equipped with an additional section, while the end of the additional section of the secondary winding through an additional di One is connected to an additional electronic key, the cathode of which is connected to the cathodes of the diodes.

Images