JPH07336884A - Dc power device - Google Patents

Abstract

PURPOSE:To provide a DC power device inhibiting inrush currents at a time when an AC power supply is turned on. CONSTITUTION:A DC power device 11 is constituted while having an SSR 12, an AC/DC converter 13, a DC power-supply backup circuit 14, a switch 15 and a DC voltage source 16 in response to an AC power supply 17 and power-supply output terminals 18 and 19, and the DC voltage of the DC voltage source 16 is input to the SSR 12 when a power supply is turned on by the switch 15. Accordingly, the AC voltage of the AC power supply 17 is applied to the AC/DC converter 13 at timing when the phase of AC voltage is zero- crossed, and converted into DC voltage, and desired DC voltage is output through the power-supply output terminals 18 and 19. The output voltage is input to the DC power-supply backup circuit 14, and the DC power supply 16 is supplied with the output DC voltage, and the output DC voltage is used jointly for charging. Inrush currents flowing into load are limited to a minimum current value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DC power supply device, and more particularly to a DC power supply device for rectifying and smoothing at least a commercial power supply to output a DC current.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a DC power supply 31 for rectifying and smoothing a general commercial power supply corresponds to an AC power supply 35 and a load 36, and a switch 32 and an AC.
The / DC converter 33 and the resistor (thermistor) 34 are provided. In FIG. 3, when the power is turned on by the switch 32, the AC / DC
AC voltage is converted to DC voltage by the converter 33,
The desired DC voltage is supplied to the load 36 through the resistor 34. In this case, as a measure against the inrush current flowing into the load 36 when the power is turned on by the switch 32, the above-mentioned resistor (thermistor) 34 is inserted in series to suppress the inrush current. Is.

[0003]

Generally, in a DC power supply device, there is a close relationship between the magnitude of the inrush current and the phase of the voltage waveform of the AC power supply when the power is turned on. However, the inrush current is minimum when the phase of the voltage waveform of the AC power supply corresponds to 0 degrees, 180 degrees, 360 degrees, ..., and the phase of the voltage waveform corresponds to 90 degrees, 270 degrees, ... When it does, it becomes the maximum.

In the above-mentioned conventional DC power supply device, a resistor (thermistor) 34 is provided in consideration of the case where the inrush current is maximum, and the rated power and the resistance value of the resistor (thermistor) 34 are set. However, there is a difference in the magnitude of the inrush current as described above depending on the timing of power-on, and the resistance value of the resistor (thermistor) 34 is set to a smaller value, and it becomes unnecessary during steady operation. There are many states in which the power consumption can be reduced. Therefore, in the conventional example, the resistance value of the resistor (thermistor) on average reduces the efficiency of the DC power supply device more than necessary. There is a drawback that.

The object of the present invention is to control the AC power source to be turned on at the time of zero crossing of the phase of the AC power source voltage waveform, regardless of the timing of turning on the AC power source. It is an object of the present invention to provide a DC power supply device capable of suppressing a low value.

[0006]

A DC power supply device according to a first aspect of the present invention comprises an AC / DC converter for inputting an AC voltage, converting the AC voltage into a DC voltage, and outputting a desired DC voltage, and a predetermined AC power supply for converting the AC / DC converter. It is inserted and connected in series to an AC voltage input line connected to the input side of the AC / DC converter, and is controlled by a predetermined DC voltage when the AC power source is turned on to control the phase of the AC voltage from the AC power source. A solid state relay which becomes conductive at the timing of zero crossing and acts so that the AC voltage is supplied to the AC / DC converter, and a DC voltage for control of the solid state relay are generated to generate the solid state relay. .DC power supply for supplying power to relay and power supply for supplying DC power to solid state relay A switch for, by inputting the DC voltage outputted from the AC / DC converter is characterized in that it comprises at least, a DC power supply backup circuit for generating and outputting a charging voltage to the DC power supply.

The DC power supply device of the second invention is an AC / DC converter which inputs an AC voltage, converts the AC voltage into a DC voltage, and outputs a desired DC voltage, and the AC / DC converter from a predetermined AC power supply. At the timing of zero crossing of the phase of the AC voltage by the AC power supply, which is inserted and connected in series with the AC voltage input line connected to the input side of the AC power supply and is controlled by a predetermined DC voltage when the AC power supply is turned on. It becomes conductive, and the AC voltage is A
A solid-state relay that operates so as to be supplied to a C / DC converter, a direct-current power supply that generates a direct-current voltage for controlling the solid-state relay, and supplies the direct-current power to the solid-state relay, and the direct-current power supply. And a switch that functions to turn on the power supplied to the solid state relay.

In the first and second aspects of the invention, the switch is used as a dedicated switch for supplying a DC voltage for control by the DC power source to the solid state relay in advance, and the AC / DC converter is used. It is also possible to newly provide a power-on switch which is inserted and connected in series to the AC voltage input line connected to the input side of.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention. As shown in FIG. 1, the DC power supply device 11 of the present embodiment corresponds to the AC power supply 17 and the power supply output terminals 18 and 19 and corresponds to a solid state relay (SO
LID STATE RELAY (hereinafter, abbreviated as SSR) 12, an AC / DC converter 13, a DC power supply backup circuit 14, a switch 15, and a DC voltage source 16.

In FIG. 1, when the power is turned on by the switch 15, the DC voltage source 16 is first supplied.
Is input to the SSR 12 as a DC voltage for control. When this power is turned on, an AC voltage from the AC power supply 17 is applied to the SSR 12 via the input impedance of the AC / DC converter 13. S
The SR12 becomes conductive at the timing when the phase of the AC voltage crosses zero, and the AC voltage of the AC power supply 17 becomes AC / DC via the SSR12 in the conductive state.
The DC voltage is applied as a regular AC voltage to the converter 13, converted into a DC voltage in the AC / DC converter 13, and a desired DC voltage is supplied to the power output terminals 18 and 19.
Is output via. In this case, in the SSR 12, in the state in which the control DC voltage is input, the SSR 12 is in the non-conduction state except at the timing when the phase of the applied AC voltage crosses zero.
Therefore, the AC / DC in the AC / DC converter 13
No voltage conversion is performed, and the voltage output terminals 18 and 19
No more DC voltage is output. The DC voltage output from the AC / DC converter 13 is output from the voltage output terminals 18 and 19 as described above, and is also input to the DC power supply backup circuit 14 to output the DC power supply device during operation. The DC voltage is supplied to the DC power supply 16 and is also used for charging the DC power supply 16.

Accordingly, the SS is controlled by the control DC voltage supplied from the DC power supply 16 to the SSR 12.
Due to the conduction characteristic of R12, the AC voltage of the AC power supply 17 is normally input to the AC / DC converter 13 at the time when the phase of the AC voltage crosses zero, so that the rush current flowing from the voltage output terminals 18 and 19 into a predetermined load when the power is turned on. Is always suppressed to the minimum current value, there is no need to use a resistor (thermistor) as in the conventional example, and unnecessary power consumption of the DC power supply device is completely eliminated.

FIG. 2 is a block diagram showing a second embodiment of the present invention. As shown in FIG. 2, the DC power supply device 21 of this embodiment includes an AC power supply 26 and a power supply output terminal 27.
Corresponding to Nos. 28 and 28, an SSR 22, an AC / DC converter 23, a switch 24, and a DC voltage source 25 are provided.

In FIG. 2, when the power is turned on by the switch 24, first, the DC voltage source 25 is supplied.
Is input to the SSR 22 as a DC voltage for control. When the power is turned on, the AC voltage from the AC power supply 26 is applied to the SSR 22 via the input impedance of the AC / DC converter 23. S
The SR22 becomes conductive at the timing when the phase of the AC voltage crosses zero, and the AC voltage of the AC power supply 26 becomes AC / DC via the SSR22 that has become conductive.
The DC voltage is applied as a regular AC voltage to the converter 23, converted into a DC voltage in the AC / DC converter 23, and a desired DC voltage is output to the power output terminals 27 and 28.
Is output via. In this case, in the SSR 22, in the state in which the control DC voltage is input, the SSR 22 is in the non-conductive state except at the timing when the phase of the applied AC voltage crosses zero.
Therefore, the AC / DC in the AC / DC converter 23
The voltage conversion function is not performed, and the voltage output terminals 27 and 28
No more DC voltage is output.

The above operation is the same as that of the first embodiment except for the operation by the DC voltage backup circuit 14.
The operations performed by the corresponding components are exactly the same. The operational difference of this embodiment from the first embodiment is that the DC / DC converter 23 shown in FIG. Is done via a direct current voltage,
That is, the charging action on the DC power supply 25 during operation is not taken into consideration. However, also in the case of the second embodiment, it can be operated as a DC power supply device without any trouble by replacing the DC power supply 25 or charging by another charging device.

Also in the case of this embodiment, the DC power supply 25
From the control DC voltage supplied to the SSR22,
Due to the conduction characteristic of the SSR 22, AC / AC is generated at the timing when the phase of the AC voltage of the AC power supply 26 crosses zero.
Since the DC converter 13 is normally input, the inrush current flowing into the predetermined load from the voltage output terminals 27 and 28 when the power is turned on is always suppressed to the minimum current value. Further, this eliminates the need to use the resistance (thermistor) found in the conventional example, and completely eliminates unnecessary power consumption of the DC power supply device.

It should be noted that the above-mentioned first shown in FIG. 1 and FIG.
In the second embodiment, the switch 15 (first embodiment) and the switch 24 (second embodiment) are connected to the SSRs corresponding to the DC voltages of the DC power supplies 16 and 25, respectively.
Used as a dedicated switch for supplying to 12 and 22, AC / DC from AC power supplies 17 and 26, respectively.
A switch for turning on the power may be separately provided on each of the voltage input lines for the converters 13 and 23.

[0018]

As described above, according to the present invention, the AC / AC
By inserting SSM in the voltage input line on the input side of the DC converter, it is possible to turn on the power by zero cross start through the control action by the predetermined DC voltage of the SSM. It is possible to suppress the electric current to the minimum level, and it is possible to remarkably reduce the power consumption.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a conventional example.

[Explanation of symbols]

 11, 21, 31 DC power supply device 12, 22 SSR 13, 23, 33 AC / DC converter 14 DC power supply backup circuit 15, 24, 32 switch 16, 25 DC power supply 17, 26, 35 AC power supply 18, 19, 27, 28 Power output terminal 34 Resistance (thermistor) 36 Load

Claims (3)

[Claims] 1. An AC voltage is input and converted into a DC voltage,
An AC / DC converter that outputs a desired DC voltage and an AC voltage input line that is connected to an input side of the AC / DC converter from a predetermined AC power source are inserted and connected in series, and when the power source is turned on by the AC power source. , Is controlled by a predetermined DC voltage, and becomes conductive at the timing when the phase of the AC voltage by the AC power supply crosses zero,
A solid state relay that acts to supply the AC voltage to the AC / DC converter; and a DC power supply that generates a DC voltage for control of the solid state relay and supplies the DC voltage to the solid state relay. A switch for supplying the DC power supply to the solid-state relay to function as a power source and a DC voltage output from the AC / DC converter are input to generate and output a charging voltage for the DC power supply. A DC power supply device comprising at least a DC power supply backup circuit. 2. An AC voltage is input and converted into a DC voltage,
An AC / DC converter that outputs a desired DC voltage and an AC voltage input line that is connected to an input side of the AC / DC converter from a predetermined AC power source are inserted and connected in series, and when the power source is turned on by the AC power source. , Is controlled by a predetermined DC voltage and becomes conductive at the timing of zero crossing of the phase of the AC voltage by the AC power source,
A solid state relay that acts to supply the AC voltage to the AC / DC converter; and a DC power supply that generates a DC voltage for control of the solid state relay and supplies the DC voltage to the solid state relay. A switch for supplying the DC power to the solid-state relay and functioning to turn on the power, at least a DC power supply device. 3. The AC / D, wherein the switch is used as a dedicated switch for previously supplying a DC voltage for control by the DC power supply to the solid state relay.
3. The DC power supply device according to claim 1, further comprising a power-on switch that is inserted and connected in series with an AC voltage input line connected to the input side of the C converter.