JPS62213571A - High-frequency phase difference control type power unit - Google Patents

Abstract

PURPOSE:To obtain an arbitrary DC output and a sinusoidal AC output with a simple power source by connecting switch elements with the primary and secondary sides of a transformer, and controlling the phase difference of switching timings of the elements. CONSTITUTION:Switches 21, 22 are connected from a power source 1 with the primary side of a transformer 3. Switches 23, 24 are connected with the secondary winding, and a reactor 8 is connected from a load 4 with the switches 23, 24. The switches 21-24 are driven by a controller 9. The controller 9 compares a sinusoidal or DC reference signal applied from a reference signal generator 91 with a voltage or current signal applied from the output to control the phase difference of switch signals applied to the switches 21, 22 and applied to the switches 23, 24, thereby controlling the output.

Description

Detailed Description of the Invention (Field of Application) The present invention relates to a power supply device that obtains arbitrary DC output, sine wave AC output, etc. from a DC power supply by switching switching elements, and particularly relates to a power supply device that provides DC isolation between the power supply side and the load side. The present invention relates to a high frequency phase difference control type power supply device that transmits power to and from the load side of the TL power supply via a high frequency transformer and controls the output voltage at the same time when it is necessary to do so. This device requires conversion from DC to AC and is uninterruptible.
It can be effectively used in a power supply device, a control drive device for an electric motor, a DC constant voltage power supply device, a constant current device, etc.

(Prior art) Many of the latest information processing devices cannot tolerate instantaneous power outages, and for this reason, AC uninterruptible power supplies that output sine wave AC output by switching switching elements rather than DC power supplies are generally widely used. used. Also in this case,
DC @ source and sine wave AC output often require DC insulation.The differences between the present invention and the prior art will be explained below using an AC uninterruptible power supply as an example.

Fig. fIs], wT2 Fig. 3, and Fig. 3 are block diagrams each showing a schematic configuration diagram of an AC power supply device that obtains a sine wave AC output from a conventional DC 1 source by switching a switch element. Codes refer to the same or equivalent parts.

In the power supply device shown in FIG. 1, power from a DC power source 1 is converted into AC by a switch device r112 that controls on/off of a switching element to obtain a sine wave AC output, and is converted to AC by a transformer 3.
Electric power is supplied to the load 4 via. However, since this device transmits low-frequency AC power to the load 4 via the transformer 3, the volume of the transformer 3 is 1! The disadvantage is that the quantity is large.

Next, in the power supply device of FIG. 2, electric power from the DC power supply 1 is converted into high-frequency AC by the DC-AC converter 5 and transmitted to the rectifier 6 via the transformer 3.

The direct current obtained by the rectifier 6 is converted into alternating current by the switching device 2 which turns on/off switching elements fft'J n to obtain a sine wave alternating current output, and power is supplied to the load 4 . Since this TLR device transmits power by high-frequency alternating current, it is possible to reduce the volume and fi amount of the transformer 3, but it has the disadvantage that the 8-circuit configuration is complicated.

Next, in the power supply device of FIG. 3, the electric power from the DC power source 1 is converted into high-frequency alternating current that is sinusoidally pulse width modulated by the switch device 2, and is transmitted to the rectifier W6 via the transformer 3, and is transmitted to the bridge circuit etc. The waveform shaping device 7 converts the signal into a sinusoidal alternating current, and supplies power to the load 4. Similar to the power supply device shown in FIG. 2, this power supply device can also reduce the volume of the transformer 3 and the amount of ffi, but has the disadvantage that the circuit configuration is complicated.

(Purpose) The present invention was made to eliminate the above-mentioned drawbacks, and its purpose is to provide a circuit for a power supply device that obtains arbitrary DC output, sine wave AC output, etc. from a DC power supply by switching a switch element. In addition to simplifying the configuration, we aim to reduce the weight per unit volume of the device, increasing the reliability of the device,
It is an object of the present invention to provide a high frequency phase difference controlled power supply device that can achieve high economic efficiency.

(Basic Principle) Fig. 4 is a diagram showing the principle of the high frequency phase difference controlled power supply device of the present invention. Further, FIG. 5 shows principle waveforms for explaining the operation of FIG. 4. In the principle diagram of the fIsd diagram, switches 21 and 22 are connected to the primary winding of the transformer 3, and switches 23 and 24 are connected to the secondary winding.The black dot shown on the 0 winding represents the polarity of the winding, and Nl:N2 represents the turns ratio of the primary and secondary windings. In principle waveforms a and b shown in FIG. 5, Sl, S2, 83 and S4 indicate on periods of the switches 21, 22, 23 and 24, respectively.

Here, the on period S3 of the switch 23 and the switch 24 is
If there is a phase difference of θ between S4 and the on-periods S1 and S2 of switches 21 and 22 as shown in FIG. A voltage waveform is generated. Here, as shown in FIG. 4, when the alternating current component is removed by filters L and C, the voltage Eo, which is the average value of the voltages shown in FIG. 5C, is obtained as an output.

Here, if the input voltage is El, the relationship between the output voltage EO and the phase difference θ is expressed by the following equation.

Eo = (1-2θ/π) Ei N2 /Nl FIG. 6 shows the result of determining the relationship between the output voltage Eo and the phase difference θ using the above equation. It can be seen from this figure that the output voltage Eo changes linearly from a positive voltage to a negative voltage with respect to a change in the phase difference θ.

By utilizing this principle, a power supply device that can obtain any DC output, sine wave AC output, etc. can be easily constructed.

(Embodiment) FIG. 7 is a block diagram showing the configuration of an embodiment of the present invention.

A switch 21 and a switch 22 are connected between the power supply 11i1 and the primary winding of the transformer 3.

A border 23 and a switch 24 are connected to the secondary winding.
A beam axle 8 is connected between the 4 and 4. Switches 21, 22, 23 and 24 are driven by control device 9. Control wave g! 9 compares a sine wave or DC reference signal provided by the reference signal generator 91 with a voltage or current signal provided from the output;
The output is controlled by controlling the phase difference between the switch signal applied to switch 22 and the switch signal applied to switches 23 and 24.

FIG. 8 is a block diagram showing a specific example of the switch element of the present invention. This figure shows an example in which bipolar transistors 21 to 24 are used as switching elements. The diodes 60-69 are for operating the transistors 21-24 as bidirectional switching elements.

In FIG. 8, a rectangular wave drive signal is applied from the control device 9 to the transistors 21-22 and the transistors 23-24 via transformers 31 and 32. Here, while one of the transistors 21 and 22 is in a conductive state, a positive voltage is generated between the base and emitter of the transistor.・Reverse voltage occurs between emitters. Therefore, transistors 21 and 22 will not become conductive at the same time, which means that transistor 23
The same applies to and 24. Therefore, there is no need to provide a special blank period or the like to prevent simultaneous conduction of the transistors, so the switching frequency can be increased. 8th
Although the figure shows an example in which a bipolar transistor is used as the switch element, it is also easy to use a switch element such as an FET (field effect transistor) as the switch element.

As is clear from the above description, 1. By using the high frequency phase difference controlled power supply device according to the present invention, it is possible to reduce the size and weight of the transformer used for insulating the DC power side and the load side. The power supply device can be implemented with a simple device, and an economical power supply device can be achieved.

[Brief explanation of drawings]

1, 2, and 3 are block diagrams showing a schematic configuration diagram of an AC power supply device that obtains a sine wave AC output by switching a switch element from a conventional DC power supply, respectively, and FIG. 5 shows waveforms for explaining the operation of FIG. 4, FIG. 6 shows the relationship between output voltage Eo and phase difference θ, and FIG.
The figure is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 8 is a block diagram showing a specific example of the switch element of the present invention. ■ ... DC power supply, 2 ... Switch device, 3 ・
...Transformer, 4...Load, 5...DC/AC converter. 6... Rectifier, 7... Waveform shaping device, 8.
...Reactor, 9 ...Control device, 21~
24...Switch, 31-32...Transformer, 60
~69...Diode, 91...Reference signal generator Fig. 1 Fig. 2! J4 figure

Claims (1)

[Claims] In a power supply device that obtains arbitrary DC output, sine wave AC output, etc. from a DC power source via a transformer by turning on and off a switch element, a switch element is connected to the primary side and secondary side of the transformer, respectively, A high frequency phase difference controlled power supply device characterized in that an arbitrary DC output, sine wave AC output, etc. can be obtained by controlling the phase difference between the switch timings of the switching elements on the primary side and the secondary side.