JPH10262347A - Backup apparatus and switching power device equipped therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a backup apparatus and a switching power source equipped with this apparatus being low-cost and not so large in size. SOLUTION: A backup apparatus 30 has a battery 32, a charger 31 for charging this battery 32, and a boosting section 35 which boosts the voltage of the battery 32 up and outputs it, and the input end of the charger 31 and the output end of the boosting section 35 are connected to the input smoothing section of a switching power section 10. Besides, a switching power device 1 is equipped with a backup apparatus 30 of the above-mentioned structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backup device for coping with problems such as a stop of output of a switching power supply device or a decrease in output voltage at the time of a power failure or a voltage drop of a power supply, and a switching power supply equipped with this device. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, as a device for maintaining constant power quality such as voltage, frequency and waveform of power supplied to a load even when a power failure, voltage drop, surge or the like occurs in a commercial power supply system. , UPS (Uninterruptible Power Supply). The UPS is basically composed of an AC / AC converter, converts input AC (alternating current) into DC (direct current), and then converts DC into AC. A battery is provided in parallel with the DC portion. It is what is being done.

When a power failure, voltage drop, surge, or the like occurs in the AC power input to the UPS, the power of the charged battery is converted to AC instead of the supplied AC power and supplied to the load. Is done.

[0004] For this reason, the UPS is used as an emergency power source in large-scale computer systems such as power plants and banks online, protection systems for substations, instrumentation systems for chemical plants, and operating rooms in hospitals. Also recently,
Since the converter is stationary and miniaturized, it is used in offices and the like for the purpose of preventing malfunctions of FA equipment and OA equipment due to instantaneous voltage drop and surge.

It is natural that the UPS is also used for stabilizing the output of the switching power supply. In this case, the UPS is connected between the commercial power system and the input terminal 11 of the switching power supply device 10, as shown in FIG. The AC from the commercial system input to the UPS is converted to DC and charges the battery, and is further converted to AC to supply power to the switching power supply 10. Even in the event of a power outage, voltage drop, surge, etc.
The output of the switching power supply does not change, and a malfunction of the load can be prevented.

[0006]

However, in the above-mentioned UPS, since the input AC is converted into DC once and then converted into AC, the circuit becomes complicated and costly, and the shape is large. Therefore, it cannot be said to be suitable as a backup device for a switching power supply.

Accordingly, an object of the present invention is to provide a backup device which is inexpensive and not large in size, and a switching power supply device provided with the backup device.

[0008]

In order to achieve the above object, a backup device according to the present invention comprises a battery, a charger for charging the battery, and a booster for boosting and outputting the voltage of the battery. Wherein the input terminal of the charger and the output terminal of the booster are connected to an input smoother of a switching power supply.

According to this configuration, when the switching power supply is connected to the commercial power supply system, the DC of the input power smoothing unit of the switching power supply is always supplied to the charger of the backup device, and the battery is charged. It is in the state that has been done. The voltage of the battery is output as DC boosted by the boosting unit to the input smoothing unit of the switching power supply device. In this case, the DC voltage boosted by the boosting unit is set to be equal to the DC voltage of the input smoothing unit of the switching power supply device.

[0010] Once a power failure or a voltage drop occurs in the commercial power supply system that supplies power to the switching power supply, the DC voltage of the input smoothing unit attempts to decrease, but the voltage from the battery boosted by the boosting unit is reduced. Since the voltage is applied to the input smoothing unit, the DC voltage of the input smoothing unit keeps its normal value. Therefore, the output of the switching power supply is not affected, and there is no possibility that the load may malfunction.

That is, with the backup device having such a simple circuit configuration, it is possible to prevent the output voltage of the switching power supply from fluctuating due to a power failure or a voltage drop of the power supply.

Further, a switching power supply unit according to the present invention converts an AC input into a DC, and further converts the DC into a desired DC output by switching, a battery, and a charger for charging the battery. A backup device having a booster for boosting and outputting the voltage of a battery, and having an input terminal of the charger and an output terminal of the booster connected to an input smoothing unit of the switching power supply unit; It is characterized by having.

With such a configuration, the switching power supply has a simple configuration and a small backup device incorporated therein, so that it can be incorporated in an OA apparatus or the like as a switching power supply with a backup device.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a switching power supply device 1 according to the present invention, which comprises a switching power supply unit 10 and a backup device 30.

First, the switching power supply unit 10 will be described. In the figure, reference numeral 11 denotes A from the commercial power system.
C is a terminal for inputting, and reference numerals 12 and 13 are output terminals of the switching power supply device 1. Reference numeral 12 is DC plus and reference numeral 13 is DC minus. 14 is a noise filter, 15 and 15 ′ are rectifiers, 16 is a smoothing capacitor,
17 is a transformer, 18 is a transistor, 19 is a switching control circuit, 20 is a photocoupler, 21 is an output detector, 22 is a rectifier, and 23 is a smoothing capacitor.

The AC input to the input terminal 11 is sent to the rectifier 15 via the noise filter 14 and rectified,
C. The noise filter 14 is inserted so that noise generated mainly by the switching operation of the switching power supply device 10 is not returned to the commercial power supply system.

A smoothing capacitor 16 for removing ripples is attached between the positive and negative terminals of the DC rectified by the rectifiers 15 and 15 '. The negative terminal is connected to one end, and the negative terminal is connected to the emitter of the transistor 18. The collector of the transistor 18 is connected to the other end on the input side of the transformer 17, and the base is configured to receive a control signal from the switching control circuit 19.

The positive terminal on the output side of the transformer 17 is connected via a rectifier 22 to the DC positive terminal 12 which is the output terminal of the switching power supply 1.
The negative terminal 13 on the output side of 7 is connected to the DC negative terminal 13 which is the output terminal of the switching power supply device 1. A smoothing capacitor 23 is attached between the DC plus terminal 12 and the minus terminal 13 as an output smoothing unit to smooth the rectified output DC voltage.

The DC voltage output between the output terminals 12 and 13 of the switching power supply 1 is detected by an output detector 21 and sent to a photocoupler 20. In the photocoupler 20, the detected electric signal sent from the output detector 21 is modulated into light by the light emitting diode, and the light is received by the phototransistor, converted into an electric signal, and input to the switching control circuit 19. The switching control circuit 19 controls the switching of the transistor 18 based on this signal so that the output terminal voltage of the switching power supply 10 becomes a predetermined value.

Next, the backup device 30 will be described.

The backup device 30 includes the charger 3
1, a battery 32, a booster 33 and a booster 35 including a rectifier 34. An input terminal of the charger 31 is connected to an output terminal of the rectifier 15 of the switching power supply 10, and a DC plus voltage is provided. Has been applied. Charger 3
A battery 32 is connected to the output terminal of the battery 1 and is charged to 24 V in this example.

A booster 33 is attached to the plus terminal of the battery 32. The output terminal of the booster 33 is connected to the positive side of the smoothing capacitor 16 of the input smoothing unit of the switching power supply 10 via the rectifier 34. It is connected. The 24 V voltage of the battery 32 is boosted by a booster 33 to an AC of 96 V in this example, and further increased by a rectifier 34.
The DC voltage is rectified and supplied to the smoothing capacitor 16 of the input smoothing unit.

In this switching power supply device 1, when an AC input from a commercial power supply system is normally applied, an output to a load is supplied only by the switching power supply unit 10.
If the AC input is stopped, that is, if there is a power failure or a voltage drop or surge, the DC voltage of the input smoothing unit will drop as it is. Accordingly, the output voltage also drops. At this time, the voltage from the battery 32 boosted by the boosting unit 35 is applied to the smoothing capacitor 16 of the input smoothing unit. The normal value will be kept as it is. Therefore, the output voltages at the output terminals 12 and 13 of the switching power supply device 1 are not affected, and there is no possibility that the load may malfunction.

[0025]

As described above, according to the present invention,
Since the circuit configuration is simple, the cost can be reduced, and the size can be reduced, so that it is suitable for use in an OA device or the like.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a switching power supply unit with a backup device according to the present invention.

FIG. 2 is a diagram in which a UPS serving as a conventional backup device is used for a switching power supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Switching power supply device 10 Switching power supply part 11 Input terminal 12, 13 Output terminal 14 Noise filter 15 Rectifier 16 Smoothing capacitor 17 Transformer 18 Transistor 19 Switching control circuit 20 Photocoupler 21 Output detector 22 Rectifier 23 Smoothing capacitor 30 Backup device 31 Battery charger 32 Battery 33 Booster 34 Rectifier 35 Booster

Claims (2)

[Claims] 1. A switching power supply device comprising: a battery; a charger for charging the battery; and a booster for boosting and outputting the voltage of the battery, wherein an input terminal of the charger and an output terminal of the booster are connected to a switching power supply. A backup device, wherein the backup device is connected to an input smoothing unit. 2. Converting the AC input to DC,
A switching power supply for converting C into a desired DC output by switching; a battery; a charger for charging the battery; and a booster for boosting and outputting the voltage of the battery, and an input of the charger. And a backup device in which an output terminal of the booster is connected to an input smoothing unit of the switching power supply.