JPH0721072Y2 - Synchronous uninterruptible power supply - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) This invention is a relatively small device such as a personal computer or an FA device, and an electric / electronic device that may suffer some troubles due to unexpected power interruption. The present invention relates to a synchronous uninterruptible power supply unit used for.

(Prior Art) Conventionally, for example, in a system of a personal computer, an FA device, and an OA device, there has been no need to deal with a power supply accident such as an unexpected power outage of a commercial power supply or an abnormal voltage drop caused by a load used during its operation. There is an uninterruptible power supply, but such an uninterruptible power supply has, for example, a charging circuit, a battery, and an inverter, and in the case of the above power supply failure, the power supply abnormality is detected and the current is supplied from the battery. . Therefore, even software assets that have been transferred to a floppy disk or a hard disk and are not protected yet, which are on the RAM of the personal computer body or the like, can be protected within a range where the destruction thereof is prevented.

(Problems to be solved by the invention) However, when a power failure occurs, that is, when the power supply system is switched, the waveform output is not necessarily continuous. The output waveform from the conventional uninterruptible power supply 1 is often as shown in FIG. 3, but the frequency of appearance of such a waveform is 1/2. The above output waveforms are the commercial power supply waveform 22 before the power outage and the inverter output waveform
There is no good continuity at 23 and the phase in the waveform is opposite phase. Therefore, for example, when the load is a transformer etc., magnetic saturation occurs when switching the power supply system and a large inrush current flows to the load. There was an occasion. For example, even with a transformer of about 5 A, a rush current of 100 A or more flows, which sometimes has a serious adverse effect on the load.

The present invention has been made to solve the problems in the above-mentioned inverter type device, and an object thereof is to provide a synchronous uninterruptible power supply device in which the inrush current at the time of switching the power supply system is suppressed to a minimum.

(Means for Solving Problems) A charging circuit for converting alternating current supplied from a commercial power source into direct current, a battery for normally storing the direct current, and an inverter for converting current supplied from the battery into alternating current,
In the uninterruptible power supply device including a through circuit that outputs the alternating current supplied from the commercial power source as it is, and a circuit switching unit that switches between the inverter side and the through side,
An input phase detection circuit that is connected to the through circuit and outputs a pulse for reporting the positive side and the negative side of the AC waveform supplied from the commercial power source, and a square wave to the positive side power source waveform through the inverter. A two-phase division circuit that divides into an odd-numbered wave to be generated and an even-numbered wave to generate a negative side power supply waveform via the inverter is provided, and the two-phase division circuit is provided by the pulse of the input phase detection circuit immediately before a power supply abnormality An output waveform synchronizing device is provided which selects a waveform divided by a phase dividing circuit and brings the commercial power source waveform and the output waveform at the time of power source abnormality into close synchronization.

(Function) The input position detection circuit detects pulse waveforms that detect the positive and negative sides of the commercial power supply until a power failure and outputs them individually from the terminals. The square wave output from the square wave generation circuit is divided into an odd number wave and an even number wave by a two-phase division circuit by a well-known waveform division method, and can be output as a drive pulse of an inverter. The inverter is adapted to shift the phase of the waveform to the load to the positive side or the negative side by inputting either the odd-numbered wave or the even-numbered wave. When a power failure occurs, the input position detection circuit outputs the pulse waveform immediately before the power failure to the two-phase division circuit. The two-phase division circuit selects the number wave corresponding to the pulse waveform. The selected number wave is input to the inverter that starts operation due to a power failure. As a result, the phase of the first waveform of the inverter is determined, the switching means operates on the side of the inverter, and the waveform of the waveform before the power failure and the waveform of the inverter shown in FIG. Are supplied to the load. Therefore,
The inrush current to the load will be suppressed to a minimum.

(Embodiment) Next, a synchronous uninterruptible power supply according to an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a synchronous uninterruptible power supply 1 according to an example of the present invention. In the figure, an input terminal 2 is a normal commercial unit 10.
It is connected to the output terminal of 0V AC power supply, that is, the outlet. The charging circuit 3 converts the alternating current supplied from the commercial power source into at least the direct current as described above, and also converts the voltage level into a predetermined voltage according to the characteristics of the battery described later. As the battery 4, for example, a sealed lead storage battery or the like is used. The inverter 5 converts direct current supplied from the battery 4 into alternating current having a voltage of 100V, for example.

The through circuit 6 is used in a normal time without a power failure or the like, and operates when the current supplied to the input terminal 2 is output as it is. The input phase detection circuit 7 is formed of, for example, a comparator. The input phase detection circuit 7 outputs pulses 11 and 12 for reporting the time of the positive side 9 and the negative side 10 of the AC waveform 8 supplied from the through circuit 6. The square wave generation circuit 13 outputs a square wave 14. The two-phase division circuit 15 is formed using, for example, a D flip-flop. This two-phase dividing circuit 15
Is the input square wave 14 is an odd waveform 16 and an even waveform
It is divided into 17, and is formed by the pulse 11 and the pulse 12 so as to allow either of them. The odd-numbered wave 16 and the even-numbered wave 17 thus selected are 1 of the inverter 5.
It becomes a drive pulse for the switching elements on both ends of the next coil. The first contact 19 of the circuit switching means 18 is normally closed, and the first contact 19 is opened and the second contact 20 is closed when the commercial power supply is abnormal such as a power failure. 100V AC such as 50 or 60HZ is output to the output terminal 21, and therefore a power input terminal of a personal computer system or the like is connected to this.

Next, an example of the operation of the synchronous uninterruptible power supply of the present invention when the power supply is abnormal will be described.

When the commercial power supply terminates with a waveform on the negative side, such as the waveform 22 in FIG. 2, and a power failure S occurs, a pulse 12 is generated (“H” level) by the input position detection circuit 7 immediately before this power failure.
And is input to the two-phase division circuit 15. Further, the two-phase division circuit 15 is allowed to output a waveform to the inverter 5 due to a power failure. The drive pulse to the inverter 5 at this time is the odd-numbered wave 17 selected by dividing the square wave 14 from the square wave generating circuit 13 by the two-phase dividing circuit 15 by inputting the pulse 12 described above. . In this way, the inverter 5
The synchronized AC output is output to the output terminal 21 when the switching means 18 operates.

(Effect of the device) The synchronous uninterruptible power supply device of the present invention having the above-mentioned configuration, when a power supply accident such as a power failure occurs and when the power supply is switched,
Since the waveforms of the commercial power supply and the uninterruptible power supply output in synchronization with each other, there is no inrush current. Therefore, an industrially significant effect such as the provision of an uninterruptible power supply device that supplies high-quality alternating current that does not adversely affect the load is achieved.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the synchronous uninterruptible power supply synchronizer of the present invention, FIG. 2 is a diagram showing a normal waveform, and FIG. 3 is a diagram showing an abnormal waveform. In the figure, 2: input terminal, 3: charging circuit, 4: battery, 5: inverter, 7: input phase detection circuit 15: two-phase division circuit, 21: output terminal.

Claims (1)

[Scope of utility model registration request] 1. A charging circuit for converting an alternating current supplied from a commercial power source into a direct current, a battery for normally storing the direct current, an inverter for converting a current supplied from the battery to an alternating current, and a power source supplied from the commercial power source. In the uninterruptible power supply consisting of a through circuit that outputs an alternating current as it is, and a circuit switching unit that switches between the inverter side and the through side, a positive side of an AC waveform supplied from a commercial power source and connected to the through circuit. An input phase detection circuit that outputs a pulse for reporting the time on the negative side, an odd-numbered wave that generates a square-side power supply waveform through the inverter, and an odd-numbered wave that generates a negative-side power supply waveform through the inverter. A two-phase dividing circuit for dividing into even-numbered waves, and dividing by the two-phase dividing circuit by a pulse of the input phase detection circuit immediately before a power failure Synchronous uninterruptible power supply, comprising an output waveform synchronizer that selects a selected waveform and brings the commercial power supply waveform and the output waveform when the power supply is abnormal close to each other.