JPH0360364A - Electric power source converter - Google Patents

Abstract

PURPOSE:To manufacture an electric power source converter easily and at a low cost without using the secondary winding of a transformer by a method wherein a transistor is turned ON and OFF and a discharge current from a capacitor is outputted through a diode. CONSTITUTION:A pulse current is applied to the base of a transistor 3 to repeat turning ON and OFF. When the transistor 3 is in an OFF stage, a current is rectified by a diode 6 through a capacitor 5 and outputted from output terminals 9a and 9b. Although the current is reduced after a certain period, when the transistor 3 is turned ON, the charge of the capacitor 5 is discharged through the transistor 3 and a diode 7. When the transistor 3 is turned OFF, the current is applied in the order of the capacitor 5, the diode 6 and the output end 9. Even if a capacitor 8 is connected, a DC current is supplied to the output end 9. Thus, an output source which outputs a voltage different from the voltage of an input source can be obtained without using the secondary winding of a transformer.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to a DC/AC converter that converts a DC power source used as a power source for operating integrated circuits such as electronic devices, motors, etc.
It relates to power converters such as inverters and DC/DC converters.

[Prior Art] FIG. 3 shows a conventional example. In FIG. 3, 3-1 is an input DC 11N, and 3-2 is a transformer. transformer 3-2
The winding 3-2 (a) and the transistor 3-3 are connected in series to the DC type [3-1].

Then, a pulse current is passed through the base of the transistor 3-3 to turn the transistor 3-3 on and off, and the first winding 3
-2 Apply a pulse current to (a).

Then, the transformed AC output is obtained from both ends 3-6 (a) and 3-6 (b) of the secondary winding 3-2 (b) of the transformer 3-2, and the diode 3-4 and capacitor 3-
5 to obtain a rectified and filtered DC voltage.

[Problems to be Solved by the Invention] However, in the conventional product as shown in Fig. 3, the transformer 3-
2 requires a secondary winding 3-2 (b), and much of the winding work is done by hand, and when installing these transformers on printed circuit boards, etc., the number of bins is large. The larger the number, the more time it takes to install it, making it uneconomical.

It is therefore an object of the invention to provide a power converter that is easy to manufacture and inexpensive.

[Means for Solving the Problems] According to the present invention, a transformer winding and a switching element are connected in series to a DC input power source.

In a power supply converter that flows an alternating current through the winding of the transformer and obtains an output from the output terminal when the switching element is turned on and off, one of the capacitors is connected to the connection between the winding of the transformer and the switching element. A diode is connected in series between the other terminal of the capacitor and the output terminal, and the connection between the other terminal of the capacitor and the diode is connected to either pole of the input power source. There is obtained a power converter characterized in that another diode is coupled between the .

〔Example] FIG. 1 shows a power converter according to one embodiment of the present invention.

Winding 1-2 of transformer 1-2 to input power supply 1-1 (a)
and transistors 1-3 are connected in series. Transistors 1-3 are repeatedly turned on and off by having a pulse current flow through their bases. When the transistor 1-3 is off, it passes through the capacitor 1-5 and is rectified by the diode 1-6, and the output terminal 1-9(a), 1
-9(b) Apply current to. Then, after a certain amount of time, capacitors 1-5 are charged and the current flowing to output terminal 1-9 decreases or stops flowing, but when transistor 1-3 turns on, capacitors 1-5 are charged. The generated charges are discharged through transistor 1-3 and diode 1-7. Then, when transistors 1-3 are turned off again, capacitor 1
-5 and diode l-6, current flows to output side 1-9. Further, by connecting the capacitor 1-8, DC power can be supplied to the output terminal 1-9. In this case, the diode 1-6 serves to prevent the current from flowing backward from the output side 1-9 when the transistor 1-3 is turned on, and at the same time to rectify the output current. As described above, it is possible to obtain an output power source having a voltage different from that of the input power source even without the secondary winding of the transformer as shown in FIG.

FIG. 2 shows a power converter according to another embodiment of the present invention. It has diodes 2-3 corresponding to diodes 1-7 in FIG. In the case of Figure 2, when transistors 2-3 are on.

Passes through diode 2-2 from output terminal 2-5 (a).

Current will flow through capacitor 2-1,
A negative voltage can be supplied to the output of the output terminal 2-5.

When the transistor is off, the charge in the capacitor 2-1 is discharged by the transformer winding and the diode 2-3.

In the case of FIGS. 1 and 2, the output voltage can be easily changed by changing the capacitance of the capacitor or by changing the on/off time of the transistor.

[Effect of the invention] As is clear from the above description, according to the present invention.

An inexpensive power converter can be easily created and has great practicality.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a power converter according to an embodiment of the present invention;
FIG. 2 is a circuit diagram of a power converter according to another embodiment of the present invention, and FIG. 3 is a circuit diagram of a conventional example. 1-1 is input DC° power supply, 1-2 is transformer, 1-2
In (a), the winding 11-3 of the transformer is a transistor 1
-5 and 1-8 are capacitors, 1-6 and 1-7 are diodes, 1-9(a) and (b) are output terminals, 2-
1 and 2-4 are capacitors, 2-2 and 2-3 are diodes, 2-5 is an output terminal, 3-1 is an input power supply, 3-2 is a transformer, 3-2(a), 3-2( 3-3 is a transistor 3-4 is a diode, and 3-5 is a capacitor 3-6 is an output terminal.

Claims (1)

[Claims] 1. A power converter that has a transformer winding and a switching element connected in series to a DC input power source, and when the switching element is turned on and off, alternating current flows through the transformer winding to obtain an output from an output terminal. One terminal of a capacitor is connected to the connection between the winding of the transformer and the switching element, a diode is connected in series between the other terminal of the capacitor and the output terminal, and a diode is connected in series between the other terminal of the capacitor and the output terminal. A power converter characterized in that another diode is coupled between a connection portion between the other terminal of the capacitor and the diode and either pole of the input power source.