JPH05161357A - Power unit - Google Patents

Abstract

PURPOSE:To make small the dimension of a transformer and lighten the weight by full wave rectifying the AC input, and converting them into high frequency by an inverter, and converting the output of the inverter into high frequency of specified voltage with an inverter, in a power unit making use of an AC-AC inverter. CONSTITUTION:AC input is converted into high frequency with an inverter 14 by the control signal of a control circuit 26, by removing the noise with a first high frequency filter 10, and rectifying the full waves with a first full wave rectifying circuit 12. The output of the inverter 14 is input into the primary coil L3 of a transformer 16, and the secondary coil L4 of the transformer 16 outputs two high frequencies where the middle taps are at zero potentials. A second full wave rectifying circuit 18 rectifies this and outputs a pulsating current of negative polarity from the pulsating current of positive polarity through a wave rectifying circuit 20. A switching circuit 22 operates according to the polarity, by the control signal of the control circuit 26, and outputs AC of low frequency, and a second high frequency filter 24 outputs it from the output end after removing noise.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, and more particularly to a power supply device for a commercial power supply whose waveform is stabilized by using a semiconductor.

[0002]

2. Description of the Related Art Conventionally, there has been known a power supply device using an AC-AC converter which removes noise from an input AC and outputs a stabilized AC. Large-capacity power supply devices use semiconductors such as thyristors to generate 50/60
And outputs the AC stabilized via a transformer and filter H _Z. The transformers and filters, 50 / 60H _Z
Because it is intended for alternating current frequencies, dozens to hundreds of KH
There is a problem that the size and weight are larger than those of transformers and the like for _Z high frequency.

As the technology related to the present invention, there are those described in JP-A-2-307366, JP-A-3-60377, and JP-A-3-49556.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a power supply device having a reduced size and a reduced weight.

[0005]

In order to achieve the above object, the invention of claim 1 provides a first full-wave rectifier circuit for full-wave rectifying an input alternating current and a first full-wave rectifier circuit output. An inverter for converting to a high frequency, a transformer for converting an inverter output to a high frequency of a predetermined voltage, a second full wave rectifying circuit for full wave rectifying the high frequency of the predetermined voltage, and a full wave by the second full wave rectifying circuit. It is configured to include a waveform shaping circuit that shapes the rectified high frequency wave to output a low frequency pulsating flow, and a switching circuit that outputs the low frequency pulsating flow according to the polarity of the alternating current.

According to a second aspect of the present invention, a first full-wave rectifier circuit for full-wave rectifying the input alternating current, an inverter for converting the output of the first full-wave rectifier circuit to a high frequency, and two high-frequency inverter outputs. A transformer with an intermediate tap for converting into two, a second full-wave rectifying circuit for full-wave rectifying the two high frequencies, and waveform shaping of the two high-frequency waves full-wave rectified by the second full-wave rectifying circuit. And a switching circuit that alternately outputs the positive and negative polarity pulsating currents according to the polarity of the alternating current.

According to a third aspect of the present invention, a first full-wave rectifier circuit for full-wave rectifying the input alternating current, an inverter for converting the output of the first full-wave rectifier circuit to a high frequency, and an inverter output of a predetermined voltage. A transformer having no intermediate tap for converting to a high frequency, a second full-wave rectifying circuit for full-wave rectifying the high frequency of the predetermined voltage, and a high-frequency wave that is full-wave rectified by the second full-wave rectifying circuit. A waveform shaping circuit that outputs a low-frequency pulsating flow, and a switching circuit that outputs by changing the polarity of the low-frequency pulsating flow so as to have a polarity according to the polarity of the alternating current. is there.

According to a fourth aspect of the present invention, a rectifying circuit for rectifying the input alternating current, a smoothing circuit for converting the output of the rectifying circuit into a direct current, an inverter for converting the smoothing circuit output into a high frequency, and an inverter output of a predetermined voltage. A transformer for converting to a high frequency, a full-wave rectification circuit for full-wave rectifying the high frequency of the predetermined voltage, and a waveform shaping for waveform shaping the high frequency wave rectified by the full wave rectification circuit to output a low frequency pulsating current. And a switching circuit that outputs the low-frequency pulsating flow based on a reference signal whose frequency is twice the output frequency.

According to a fifth aspect of the present invention, a rectifying circuit for rectifying the input alternating current, a smoothing circuit for converting the output of the rectifying circuit into a direct current, an inverter for converting the output of the smoothing circuit into a high frequency, and two high frequencies for the inverter output. A transformer with an intermediate tap for converting into a full-wave rectification circuit for full-wave rectifying the two high-frequency waves, and two high-frequency waves that are full-wave rectified by the full-wave rectification circuit for waveform shaping. The waveform shaping circuit that outputs a pulsating flow and the switching circuit that alternately outputs the positive and negative pulsating flows based on a reference signal whose frequency is twice the output frequency are configured.

According to a sixth aspect of the present invention, a rectifying circuit for rectifying the input alternating current, a smoothing circuit for converting the output of the rectifying circuit into a direct current, an inverter for converting the smoothing circuit output into a high frequency, and a predetermined inverter output. A transformer not having an intermediate tap for converting into a high frequency of voltage, a full wave rectifying circuit for full wave rectifying the high frequency of the predetermined voltage, and a low frequency of a high frequency wave which is full wave rectified by the full wave rectifying circuit. A waveform shaping circuit that outputs a pulsating flow, and a switching that changes and outputs the polarity of the low-frequency pulsating flow so that the frequency has a polarity corresponding to the polarity of the alternating current based on a reference signal that is twice the output frequency. And a circuit.

[0011]

According to the first full-wave rectification circuit of the first aspect of the present invention, the input alternating current is full-wave rectified. Thereby, for example, a positive pulsating current is obtained. Inverter converts the first full-wave rectifier circuit output to the high frequency of several tens to several hundreds KH _Z. The transformer converts the inverter output into a high frequency wave having a predetermined voltage. The transformer for converting a high-frequency, conventional 50 / 60H _Z
It can be smaller in size and lighter in weight than a transformer for a car. The second full-wave rectifier circuit full-wave rectifies the high frequency wave of the predetermined voltage converted by the transformer. The waveform shaping circuit waveform-shapes the high frequency wave that has been full-wave rectified by the second full wave rectification circuit, and outputs a low-frequency pulsating flow formed by connecting peaks of the high frequency wave. The switching circuit outputs the low-frequency pulsating flow output from the waveform shaping circuit according to the polarity of the alternating current input to the first full-wave rectifier circuit. For example, the switching circuit outputs a positive pulsating current when the alternating current has a positive polarity, and outputs a negative pulsating current when the alternating current has a negative polarity. As a result, the switching circuit outputs alternating current according to the input alternating current.

The transformer of the second aspect of the present invention is provided with an intermediate tap, and the transformer has an inverter output of 2
Convert to two high frequencies. The second full-wave rectifier circuit full-wave rectifies the two high frequencies converted by the transformer. The waveform shaping circuit waveform-shapes the two high frequencies that are full-wave rectified by the second full-wave rectification circuit, and outputs positive and negative pulsating currents formed by connecting the peaks of the high frequencies. The switching circuit alternately outputs the low-frequency pulsating flow output from the waveform shaping circuit according to the polarity of the alternating current input to the first full-wave rectification circuit. For example, the switching circuit outputs a positive pulsating current when the alternating current has a positive polarity, and outputs a negative pulsating current when the alternating current has a negative polarity. As a result, the switching circuit outputs alternating current according to the input alternating current.

The transformer of the third aspect of the invention is not provided with an intermediate tap, and the transformer converts the inverter output into a high frequency wave of a predetermined voltage. The second full-wave rectifier circuit full-wave rectifies the high frequency wave of the predetermined voltage converted by the transformer. The waveform shaping circuit waveform-shapes the high frequency wave that has been full-wave rectified by the second full wave rectification circuit, and outputs a low-frequency pulsating flow formed by connecting peaks of the high frequency wave. The switching circuit changes the polarity of the low-frequency pulsating flow so that the output has a polarity corresponding to the polarity of the alternating current, and outputs it. As a result, the switching circuit outputs alternating current according to the input alternating current.

The rectifying circuit of the invention of claim 4 rectifies the input alternating current, and the smoothing circuit smooths the output of the rectifying circuit to convert it into direct current. As a result, for example, a positive direct current is obtained.
Inverter converts the smoothing circuit output to the high frequency of several tens to several hundreds KH _Z. The transformer converts the inverter output into a high frequency wave having a predetermined voltage. The transformer for converting the high frequency, it is possible to reduce the weight with compared to a conventional 50 / 60H transformer for _Z to reduce the dimensions. The full-wave rectifier circuit full-wave rectifies the high frequency of the predetermined voltage converted by the transformer. The waveform shaping circuit waveform-shapes the high-frequency wave that has been full-wave rectified by the full-wave rectification circuit, and outputs a low-frequency pulsating flow formed by connecting high-frequency peaks. The switching circuit is based on a reference signal whose frequency is twice the output frequency,
The low frequency pulsating flow output from the waveform shaping circuit is output.
The frequency of this reference signal is, for example, an output frequency of 50H.
_Z becomes 120H _Z when the 100H _Z, 60H _Z when the.

The transformer of the invention of claim 5 is provided with an intermediate tap, and this transformer has an inverter output of 2
Convert to two high frequencies. The second full-wave rectifier circuit full-wave rectifies the two high frequencies converted by the transformer. The waveform shaping circuit waveform-shapes the two high frequencies that are full-wave rectified by the second full-wave rectification circuit, and outputs positive and negative pulsating currents formed by connecting the peaks of the high frequencies. The switching circuit alternately outputs the low-frequency pulsating flow output from the waveform shaping circuit according to the polarity of the alternating current input to the first full-wave rectification circuit. For example, the switching circuit outputs a positive pulsating current when the alternating current has a positive polarity, and outputs a negative pulsating current when the alternating current has a negative polarity. As a result, the switching circuit outputs alternating current according to the input alternating current.

The transformer of the sixth aspect of the invention is not provided with an intermediate tap, and the transformer converts the output of the inverter into a high frequency wave of a predetermined voltage. The second full-wave rectifier circuit full-wave rectifies the high frequency wave of the predetermined voltage converted by the transformer. The waveform shaping circuit waveform-shapes the high frequency wave that has been full-wave rectified by the second full wave rectification circuit, and outputs a low-frequency pulsating flow formed by connecting peaks of the high frequency wave. The switching circuit changes the polarity of the low-frequency pulsating flow so that the output has a polarity corresponding to the polarity of the alternating current, and outputs it. As a result, the switching circuit outputs alternating current according to the input alternating current.

According to the inventions of claims 1, 2, 3, 4, 5 and 6, high-frequency filters are provided on the input and output sides of the power supply device to remove noise and obtain more stabilized alternating current. In addition, the input side high frequency filter can prevent noise from being output from the input end to the outside.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, the input terminal is provided with a first high frequency filter 10 including a capacitor C1, a capacitor C2 and a coil L1. Diodes D1 to D4 are provided at the output end of the first high-frequency filter 10.
The first full-wave rectification circuit 12 in which the bridge connection is made is connected. An inverter 1 in which transistors TR1 to TR4 are bridge-connected to the output terminal of the first full-wave rectifier circuit 12
4 is connected. The output terminal of the inverter 14 is connected to the primary coil L3 of the transformer 16. Transformer 16
The secondary coil L4 is provided with an intermediate tap. Two
Both ends of the next coil L4 are connected to a second full-wave rectifier circuit 18 in which diodes D5 to D8 are bridge-connected like the first full-wave rectifier circuit 12. Second full-wave rectifier circuit 1
The output terminal of 8 is a coil L5, a capacitor C5, and a resistor R.
1 and a series-parallel circuit, a coil L6 and a capacitor C
It is connected to a waveform shaping circuit 20 in which a serial-parallel circuit composed of 6 and a resistor R2 is connected in series. The connection point of this series-parallel circuit is connected to the intermediate tap of the transformer 16. The output terminal of the waveform shaping circuit 20 has transistors TR5 and TR.
6 is connected in series to the switching circuit 22. The connection point between the transistor TR5 and the transistor TR6 is a capacitor C3, a capacitor C4 and a coil L2.
Is connected to the second high frequency filter 24.
The input terminal of the second high frequency filter 24 is the transformer 1
It is connected to 6 middle taps.

The first full-wave rectifier circuit 12 and the inverter 14
A sensor SH1 that detects the currents of the transistors TR1 to TR4 and outputs the current to the control circuit 26 is provided between and. The output terminal of the first high-frequency filter 10 is connected to the power supply terminal POW of the control circuit 26. The first control terminals B1 to B4 of the control circuit 26 are connected to the bases of the transistors TR1 to TR4 of the inverter 14, respectively.

A sensor SH2 for detecting the output current of the switching circuit 22 and outputting it to the control circuit 26 is provided between the switching circuit 22 and the second high frequency filter 24. The second control terminals B5 to B6 of the control circuit 26 are the transistors T of the switching circuit 22.
They are connected to the bases of R5 and TR6, respectively. The terminal V is an input terminal for monitoring the output waveform,
The terminal T is an input terminal for preventing overheating of the device, and the switch Th is a temperature detection switch.

Next, the operation of this embodiment will be described with reference to the waveforms shown in FIG. The alternating current indicated by the waveform of A in FIG. 2 is input from the input terminal and the noise is removed by the first high-frequency filter 10, and then the first full-wave rectifier circuit 12 and the control circuit 2
6 is input to the power supply terminal POW. Note that another purpose of the high frequency filter 10 is to prevent noise from being output from the input end. The first full-wave rectifier circuit 12 is
The input alternating current is full-wave rectified, and the pulsating flow shown in B of FIG. 2 is output. The control circuit 26 includes transistors TR1 to TR4.
Transistor TR by controlling the base current of
And off the 1～TR4, converting the first full-wave rectifier circuit 12 outputs the tens to hundreds of KH _Z a high frequency of approximately shown in C of FIG. At this time, the current flowing through the transistors TR1 to TR4 is detected by the sensor SH1 and the control circuit 26
Is based on this detection value and is based on the transistors TR1 to TR4.
Is controlled so that the output of the inverter 14 becomes a predetermined value or less. In this way, when the detection value of the sensor SH1 exceeds the predetermined value, the on output to the transistor is stopped, so that the transistor can be protected even if the input AC voltage fluctuates to increase.

The high frequency output from the inverter 14 is
It is input to the primary coil L3 of the transformer 16. Transformer 16
In the secondary coil L4, two high frequencies with the middle tap at zero potential are induced. One high frequency is diode D
After being full-wave rectified by 5 and D6, it is converted by the coil L5, the capacitor C5, and the resistor R1 into a low-frequency pulsating flow in which the peaks of the full-wave rectified high frequencies are connected. on the other hand,
The other high frequency wave is full-wave rectified by the diodes D7 and D8, and then the coil L6, the capacitor C6, and the resistor R2.
Is converted into a low-frequency pulsating flow in which high-frequency peaks subjected to full-wave rectification are connected. As a result, the positive pulsating flow shown in D of FIG. 2 is output to the cathode side of the second full-wave rectifying circuit 18, and the negative pulsating flow shown to E of FIG. 2 is output to the anode side. ..

The control circuit 26 outputs an ON signal from the control terminal B5 to turn on the transistor TR5 when the alternating current input to the power supply terminal POW has a positive polarity. When the alternating current input to the power supply terminal POW has a negative polarity, an ON signal is output from the control terminal B6 to turn on the transistor TR6. As a result, the switching circuit 22 obtains an alternating current having a waveform shown by F in FIG. The sensor SH2 detects the current output from the switching circuit 22, and the control circuit 26 controls the on-time of the transistors TR5 and TR6 based on the detected value so that the output of the switching circuit 22 does not exceed a predetermined value. As a result, the transistors TR5 and TR6 can be protected. The output of the switching circuit 22 is output from the output terminal after noise is removed by the second high frequency filter 24.

As described above, according to this embodiment, the weight can be reduced as compared with the conventional AC-AC converter transformer, and the degree of freedom in size and shape can be increased to stabilize the output. It can be performed easily, at high speed and with high accuracy. Therefore, it is possible to combine various DC outputs, and it is possible to set and limit the peak current at the start of operation.

Further, this embodiment has the following advantages as compared with other converters. (1) The DC circuit does not require a large-capacity electrolytic capacitor or the like.

(2) Since the input and output are synchronized, the power factor does not decrease much. (3) at an output frequency of 50 / 60H _Z, by the use of an inverter which performs high-frequency switching, primary / secondary insulation,
It is possible to reduce the size and weight.

[0027] (4) 50 / 60H _Z output frequency, the use of pulsating power frequency, a high frequency filter for the output waveform shaping small, can be reduced in weight.

(5) Since it is converted into a high frequency, it is good for an output of medium capacity. (6) Since the output currents of the inverter and the switching circuit are controlled so as not to exceed a predetermined value, various outputs are possible.

(7) Since the input and output are synchronized, the fluctuation of the power factor can be reduced with respect to the fluctuation of the load.

In the first embodiment described above, the secondary coil L4 of the transformer 16 is described as having the intermediate tap, but the transformer 16 without the intermediate tap can also function similarly. Next, a second embodiment of the present invention using the transformer without the intermediate tap will be described with reference to FIG.

In this embodiment, the secondary side circuit of the transformer of the first embodiment is modified. Therefore, in FIG.
The same reference numerals are given to the parts corresponding to, and the description will be omitted.
As shown in FIG. 5, the secondary coil L4 of the transformer 16 is changed to one without an intermediate tap, the waveform shaping circuit 20 is one circuit including the coil L5, the capacitor C5, and the resistor R1, and the switching circuit 22 is further provided. Is the transistor TR
7, TR8 is added to bridge-connect the transistors TR5 to TR8, and the transistors TR5 and TR are connected.
8 and the transistors TR6 and TR7 are controlled by the control circuit 26 so as to be turned on at the same time.

Next, the operation of this embodiment will be described with reference to the waveforms shown in FIG. 6A to 6C are similar to FIGS. 2A to 2C.

The high frequency wave of C in FIG. 6 output from the inverter 14 is induced in the secondary coil L4 of the transformer 16 and full-wave rectified by the diodes D5 to D8 so that the pulsating current shown in D of FIG. It is output from the rectifier circuit 18. This pulsating flow is shaped by the waveform shaping circuit 20 including the coil L5, the capacitor C5, and the resistor R1 and converted into the low-frequency pulsating flow indicated by E in FIG. 6 and output to the switching circuit 22.

The control circuit 26 controls the control terminals B5 and B8 when the alternating current input to the power supply terminal POW is positive.
Outputs an ON signal from the transistors and simultaneously turns on the transistors TR5 and TR8. When the alternating current input to the power supply terminal POW has a negative polarity, ON signals are output from the control terminals B6 and B7 to simultaneously turn on the transistors TR6 and TR7 and invert the polarity of the pulsating current. by this,
From the switching circuit 22, an alternating current having a waveform shown by F in FIG. 6 is obtained. Note that, conversely to the above, when the alternating current is the positive electrode, the pulsating flow may be reversed.

Needless to say, this embodiment has substantially the same advantages as the first embodiment.

Next, a third embodiment of the present invention will be described with reference to FIG. In this embodiment, a smoothing circuit and a switch for designating an output frequency are provided in the first embodiment. Therefore, in FIG. 3, parts corresponding to those in FIG. As shown in FIG. 3, the output terminal of the first full-wave rectifier circuit 12 is connected to a capacitor CO that constitutes a smoothing circuit. A half-wave rectifier circuit may be used instead of the first full-wave rectifier circuit. Control circuit 26
Has an input terminal F for designating the frequency of the output waveform to 50Hz or 60Hz. To designate the frequency of the output waveform to 50Hz or 60Hz regardless of the frequency of the input waveform at this terminal F. The frequency specifying switch Fr is provided. For example, when the switch Fr is on, the designated frequency is 50 Hz, and when it is off, the designated frequency is 60 Hz.

Next, the operation of this embodiment will be described with reference to the waveforms shown in FIG. In addition, below, the example which converts 60 Hz input into 50 Hz and outputs it is demonstrated. The 60 Hz alternating current indicated by the waveform of A in FIG. 4 is input from the input end, noise is removed by the first high frequency filter 10, and then the first
Power supply terminal POW of the full-wave rectifier circuit 12 and the control circuit 26
Entered in. The first full-wave rectifier circuit 12 full-wave rectifies the input alternating current, and the capacitor CO smoothes the output of the first full-wave rectifier circuit and outputs the direct current shown in B of FIG. The control circuit 26 controls the base currents of the transistors TR1 to TR4 to control the transistors TR1 to TR4.
And off and converted into a high frequency the frequency of the waveform had been several tens to several hundreds of KH _Z about a and a peak showing the direct current is smoothed by the capacitor CO to C in FIG. 4 is 100 Hz.
In order to generate such a high frequency, the generation frequency shown in G of FIG.
A reference signal of 0 Hz is generated, the output of the inverter 14 becomes a predetermined value or less based on the detection value of the sensor SH1, and the frequency of the waveform in which the peaks of the output of the inverter 14 are continuous is 10
The transistors TR1 to TR4 may be pulse-modulated so that the frequency becomes 0 Hz. In this way, when the detection value of the sensor SH1 exceeds the predetermined value, the ON output to the transistor is stopped, so that the transistor can be protected even if the input AC voltage fluctuates to increase.

The high frequency output from the inverter 14 is
It is input to the primary coil L3 of the transformer 16. Transformer 16
In the secondary coil L4, two high frequencies with the middle tap at zero potential are induced. One high frequency is diode D
After the full-wave rectification by 5, D6, the coil L5, the capacitor C5, and the resistor R1 convert the frequency in which the peaks of the full-wave rectified high frequencies are combined into a pulsating flow of 100 Hz. On the other hand, the other high frequency wave is full-wave rectified by the diodes D7 and D8, and then the coil L6 and the capacitor C
The frequency in which the peaks of the high-frequency waves that are full-wave rectified by 6 and the resistor R2 are connected are converted into a pulsating flow of 100 Hz. As a result, the positive pulsating flow shown in D of FIG. 4 is output to the cathode side of the second full-wave rectifying circuit 18, and the negative pulsating flow shown to E of FIG. 4 is output to the anode side. ..

The control circuit 26 alternately outputs the ON signal synchronized with the reference signal of 100 Hz from the control terminals B5 and B6 so that the frequency designated by the terminal F becomes an alternating current of 50 Hz, and the transistors TR5 and TR6 are turned on. Turn on alternately. As a result, the switching circuit 22 obtains an alternating current having a waveform indicated by F in FIG. Sensor SH
2 detects the current output from the switching circuit 22, and the control circuit 26 uses the detected value to prevent the output of the switching circuit 22 from exceeding a predetermined value.
It controls the on time of R5 and TR6. As a result, the transistors TR5 and TR6 can be protected.
The output of the switching circuit 22 is the second high frequency filter 24.
After noise is removed by, the signal is output from the output end.

Although an example of converting 60 Hz to 50 Hz has been described above, the frequency of the waveform of the high frequency peaks output from the inverter 14 is 120 Hz.
If the transistors TR5 and TR6 are alternately turned on by the ON signal synchronized with the 120 Hz reference signal, 50H
z can be converted to 60 Hz. Further, if the frequency of the above waveform is set to a predetermined value, an alternating current having a frequency half the predetermined value can be obtained.

In the third embodiment, as in the first embodiment, a circuit example using a transformer with an intermediate tap has been described, but a transformer without an intermediate tap as in the second embodiment is used. However, it goes without saying that it can be implemented.

As described above, according to the third embodiment,
The same effects as those of the first embodiment can be obtained, and the following advantages can be obtained.

(1) It is easy to change the output frequency between 50/60 Hz. (2) The input and output are operated synchronously and the capacitor CO
It is possible to improve the power factor by reducing the capacity of.

Further, by using the input side circuit of the transformer 16, that is, the first high-frequency filter 10, the first full-wave rectifier circuit 12 and the inverter 14, three sets of circuits are connected in parallel, respectively. A phase power source can be input, and a three-phase / single-phase converter with good load balance can also be obtained.

Further, such a power supply unit is used in a developing processor for a photographed photo film or a 200 V / printer in a printing processor.
When applied as a 100V step-down device, the following effects can be obtained.

(1) The overall size and weight of the device can be reduced. (2) The output frequency can be made uniform irrespective of the frequency of the input power source, the processor side need not be changed, and the processing quality can be maintained.

Further, the specifications of the processing machine and the types of parts used can be unified, and parts management during manufacturing becomes easy.

(3) Since the output frequency is automatically set by receiving the frequency designation signal corresponding to the specified frequency on the processor side, the user can use the output power frequency without being aware of the input power frequency.

(4) Since the transformer and the like can be made compact and lightweight, it is easy to add a DC output function of ± 5V / ± 12V by making a plurality of secondary coils, rectifier circuits, switching circuits, etc. Is.

[0050]

As described above, according to the first, second and third aspects of the present invention, since the high frequency is converted into the high frequency by the inverter and then input to the transformer, the size of the transformer is reduced and the weight is reduced. Therefore, it is possible to provide a power supply device having a small size and a small weight. According to the inventions of claims 4, 5, and 6, claims 1, 2, and
It is possible to provide a power supply device having a small size and weight and a frequency conversion function by combining the invention of 3 with a frequency switching function.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a first embodiment of the present invention.

FIG. 2 is a diagram showing a waveform of each part of FIG.

FIG. 3 is a circuit diagram of a third embodiment of the present invention.

FIG. 4 is a diagram showing a waveform of each part of FIG.

FIG. 5 is a circuit diagram of a second embodiment of the present invention.

6 is a diagram showing a waveform of each part of FIG.

[Explanation of symbols]

 CO-C6 capacitors L1, L2, L5, L6 coil L3 primary coil L4 secondary coil 10 first high-frequency filter 12 first full-wave rectifier circuit 14 inverter 16 transformer 18 second full-wave rectifier circuit 20 waveform shaping Circuit 22 Switching circuit 24 Second high frequency filter 26 Control circuit

Claims (6)

[Claims] 1. A first full-wave rectifier circuit for full-wave rectifying the input alternating current, an inverter for converting the output of the first full-wave rectifier circuit to a high frequency, and a transformer for converting the inverter output to a high frequency of a predetermined voltage. And a second full-wave rectification circuit for full-wave rectifying the high frequency of the predetermined voltage, and a waveform for shaping the high frequency wave full-wave rectified by the second full-wave rectification circuit to output a low-frequency pulsating flow. A power supply device comprising: a shaping circuit; and a switching circuit that outputs the low-frequency pulsating flow according to the polarity of the alternating current. 2. A first full-wave rectifier circuit for full-wave rectifying the input alternating current, an inverter for converting the output of the first full-wave rectifier circuit to a high frequency, and an intermediate tap for converting the inverter output into two high frequencies. With a transformer, a second full-wave rectifier circuit for full-wave rectifying each of the two high frequencies, and two positive and negative polarities obtained by waveform-shaping the two high-frequency waves rectified by the second full-wave rectifier circuit. And a switching circuit that alternately outputs the positive and negative pulsating currents according to the polarity of the alternating current. 3. A first full-wave rectifier circuit for full-wave rectifying the input alternating current, an inverter for converting the output of the first full-wave rectifier circuit to a high frequency, and an intermediate for converting the inverter output to a high frequency of a predetermined voltage. A transformer without a tap, a second full-wave rectification circuit for full-wave rectifying the high frequency of the predetermined voltage, and a low-frequency pulse by waveform-shaping the high-frequency rectified by the second full-wave rectification circuit. A power supply device comprising: a waveform shaping circuit that outputs a flow; and a switching circuit that changes the polarity of the low-frequency pulsating flow so as to have a polarity according to the polarity of the alternating current and outputs the polarity. 4. A rectifying circuit for rectifying the input alternating current, a smoothing circuit for converting the output of the rectifying circuit into a direct current, an inverter for converting the output of the smoothing circuit into a high frequency, and a transformer for converting the inverter output into a high frequency of a predetermined voltage. A full-wave rectifier circuit for full-wave rectifying the high frequency of the predetermined voltage, a waveform shaping circuit for waveform shaping the high frequency wave which is full-wave rectified by the full-wave rectifier circuit, and outputting a low-frequency pulsating flow, A switching circuit that outputs the low-frequency pulsating flow based on a reference signal that is twice the output frequency. 5. A rectifying circuit for rectifying the input alternating current, a smoothing circuit for converting the output of the rectifying circuit into a direct current, an inverter for converting the output of the smoothing circuit into a high frequency, and an intermediate tap for converting the inverter output into two high frequencies. With a transformer, a full-wave rectifier circuit for full-wave rectifying each of the two high frequencies, and two high-frequency waves that have been full-wave rectified by the full-wave rectifier circuit for waveform shaping to output positive and negative pulsating currents. A power supply device comprising: a waveform shaping circuit; and a switching circuit that alternately outputs the positive and negative pulsating currents based on a reference signal whose frequency is twice the output frequency. 6. A rectifier circuit for rectifying the input alternating current, a smoothing circuit for converting the output of the rectifier circuit into a direct current, an inverter for converting the output of the smoothing circuit into a high frequency, and an intermediate for converting the inverter output into a high frequency of a predetermined voltage. A transformer without a tap, a full-wave rectifier circuit that full-wave rectifies the high frequency of the predetermined voltage, and a waveform shaping that outputs a low-frequency pulsating current by shaping the high-frequency wave that is full-wave rectified by the full-wave rectifier circuit. A power supply device including: a circuit; and a switching circuit that changes and outputs the polarity of the low-frequency pulsating flow so that the frequency becomes a polarity corresponding to the polarity of the alternating current based on a reference signal that is twice the output frequency. ..