JPH0613353U - Uninterruptible power system - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an uninterruptible power supply device capable of easily and reliably managing the power supplied from an inverter to a load. [Composition] A commercial power supply terminal 1 and an inverter 4 are selectively connected to a load 3 via first and second switches 2 and 5. Buzzer 1 when a power failure is detected by the power failure detection circuit 8
0 sounds. Switch 11 for stopping the buzzer 10
Is turned on and the buzzer 10 is not operating,
When the voltage of the storage battery 6 as the power source of the inverter 4 drops, the buzzer 10 sounds again.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an uninterruptible power supply configured to supply power from an inverter to a load when a commercial power supply fails.

[0002]

[Prior art]

 An uninterruptible power supply for a computer system or the like is configured to connect an inverter power supply to a load when the commercial power supply fails.

[0003]

[Problems to be solved by the device]

 By the way, since the inverter power supply is configured to drive the inverter with the storage battery, if the power supply from the inverter is continued, the voltage of the storage battery drops and it becomes impossible to supply the power to the load. If the power supply from the inverter power supply suddenly becomes impossible, the problem of data loss or destruction will occur in the load of the computer. Some uninterruptible power supplies are equipped with an alarm buzzer to inform them of a power failure. However, this kind of device is equipped with a switch to turn off the buzzer sound when it is hard to hear. Therefore, if the load continues to operate with this switch turned off, the power supply to the load suddenly becomes impossible and a failure may occur.

Therefore, an object of the present invention is to provide an uninterruptible power supply device capable of easily and reliably managing the power supply from the inverter.

[0005]

[Means for Solving the Problems]

 The present invention for achieving the above object includes a commercial power supply terminal, a storage battery, an inverter connected to the storage battery, and a switch means for selectively connecting the commercial power supply terminal and the inverter to a load. In the provided uninterruptible power supply device, an amount of stored electricity that detects whether or not the amount of stored electricity in the storage battery has decreased below a predetermined value due to discharge of the storage battery based on the stop of the supply of commercial AC power from the commercial power supply terminal. The present invention relates to an uninterruptible power supply device, comprising: a detection circuit; and an alarm device that issues an alarm in response to a signal indicating that the storage amount detection circuit detects the predetermined value or less. As described in claim 2, an alarm can be generated even when the output of the power failure detection circuit is provided, and further, operation means for arbitrarily setting the transmission period of the signal indicating the power failure detection can be provided.

[0006]

[Operation and effect of the device]

 The storage amount detection circuit of the uninterruptible power supply of the present invention determines the storage amount of the storage battery (remaining storage amount) by the output voltage of the storage battery, the discharge time, the product of the discharge current and the discharge time, or a combination thereof. It is detected whether it is less than or equal to the value. When the amount of electricity stored falls below a predetermined value, an alarm is issued, so it is possible to take measures so that no trouble occurs even if the power supply from the inverter to the load is stopped. According to the second aspect of the present invention, even if the period for sending out the alarm based on the detection of the power failure is arbitrarily set by the operating means, the warning is generated when the storage amount of the storage battery becomes equal to or less than the predetermined value. It is possible to operate the load so that no fault occurs in the load.

[0007]

【Example】

 Next, an uninterruptible power supply according to an embodiment of the present invention will be described with reference to FIGS. In FIG. 1, a commercial power supply terminal 1 connected to a commercial power supply is connected to a load 3 composed of a computer system via a first switch 2. The inverter (DC-AC converter) 4 is connected to the load 3 via the second switch 5. The first and second switches 2 and 5 are switch means for selectively connecting the commercial power supply terminal 1 and the inverter 4 to the load 3, and are shown as mechanical switches in FIG. It can be replaced by an electronic switch such as a transistor.

The inverter 4 is connected to the storage battery 6, converts the DC voltage of the storage battery 6 into an AC voltage, and supplies the AC voltage to the load 3. The storage battery 6 is, for example, a lead battery and is charged by a charging circuit 7 between the commercial power supply terminal 1 and the storage battery 6.

The power failure detection circuit 8 connected to the commercial power supply terminal 1 includes a voltage comparator, which detects that the commercial power supply voltage has fallen below a predetermined reference value, and indicates a power failure at a high level ( The detection signal of H) is output. The output line of this power failure detection circuit 8 is connected to the control terminals of the first and second switches 2 and 5, and the high level power failure detection signal turns off the first switch 2 and vice versa. The switch 5 of 2 is turned on. While the power is being supplied from the commercial power source, the output of the power failure detection circuit 8 is at a low level (L), and the first switch 2 is turned on and the second switch 5 is turned off.

The output line 8a of the power failure detection circuit 8 is connected to the control circuit 9, and the control circuit 9 is connected to the buzzer 10 as an alarm means via the output line 9a. A normally open buzzer stop switch 11 is provided between the power supply terminal 12 and the control circuit 9 as an operating means for arbitrarily setting the energizing period of the buzzer 10 according to the power failure detection signal.

The voltage drop detection circuit 13 as a storage amount detection circuit connected to the storage battery 6 detects whether or not the storage amount (remaining amount) of the storage battery 6 is below a predetermined value. The voltage comparator is configured to detect whether or not the voltage of 6 has become a predetermined value or less, and when the voltage has become a predetermined value or less, a signal indicating a high level (H) voltage drop is output. The output line 13a of the voltage drop detection circuit 13 is connected to the control circuit 9. The control circuit 9 activates the buzzer 10 in response to a signal indicating a voltage drop on the line 13a. The urging of the buzzer 10 by the signal indicating the voltage drop occurs regardless of the operation of the buzzer stop switch 11.

The output line 14 a of the overcurrent / overvoltage detection circuit 14 is also connected to the control circuit 9. The overcurrent overvoltage detection circuit 14 generates a high level alarm signal when the inverter 4 and the load 3 are overcurrent and overvoltage.

As shown in FIG. 2, the control circuit 9 includes resistors R1 and R2, a capacitor C1, a D flip-flop 20, a NOT circuit 21, a pulse generation circuit 22, an AND gate 23, and an OR gate 24. It is composed of an AND gate 25 and an OR gate 26. The output line of the switch 11 connected to the power supply terminal 12 is connected to the clock input terminal CK of the flip-flop 20 through a chattering prevention circuit composed of resistors R1 and R2 and a capacitor C1. Therefore, when the switch 11 is turned on to generate the pulse shown in FIG. 3D, the state of the data input terminal D of the flip-flop 20 is latched. This phase inversion output terminal is connected to the data input terminal D of the flip-flop 20, the reset terminal R is connected to the ground, and the set terminal S is connected to the output line 8a of the power failure detection circuit 8 via the NOT circuit 21. ing. In the non-power-off state, the line 8a is at the low level, the output of the NOT circuit 21 is at the high level, the flip-flop 20 is in the set state, the positive phase output line 20a is at the high level, and the negative phase output line 20b is at the low level. Becomes Even if the output of the flip-flop 20 is high during this non-power failure period, the output of the AND gate 25 becomes low because the line 8a is low, and the buzzer 10 is not activated. Further, when there is no power failure, the output state of the flip-flop 20 does not change even if the switch 11 is erroneously turned on because the set terminal S is at a high level. On the other hand, in the power failure state, the set terminal S of the flip-flop 20 becomes low level. Therefore, when the switch 11 is turned on, a clock pulse is given to the clock input terminal CK of the flip-flop 20, and the flip-flop 20 becomes the data input terminal. The low level of the child D is latched, and the positive phase output line 20a is converted to the low level.

Since one input terminal of the AND gate 23 is connected to the output line 20 a of the flip-flop 20 and the other input terminal is connected to the pulse generation circuit 22, the output of the flip-flop 20 is at a high level. At times, a pulse train that is repeatedly generated from the pulse generation circuit 22 at a constant cycle is passed, and when the output of the flip-flop 20 is at a low level, the passage of the above pulse train is blocked. One input terminal of the OR gate 24 is connected to the AND gate 23, and the other input terminal is connected to the output line 13a of the voltage drop detection circuit 13. One input terminal of the AND gate 25 is connected to the OR gate 24, and the other input terminal is connected to the output line 8a of the power failure detection circuit 8. One input terminal of the OR gate 26 is connected to the AND gate 25, and the other input terminal is connected to the output line 14a of the overvoltage / overcurrent detection circuit 14, and this output line 9a is connected to the buzzer 10 of FIG. ing. The output pulse train of the pulse generation circuit 22 passes through the AND gate 23 and the OR gate 24 at the time of non-power failure, but is blocked by the AND gate 25. That is, since the output of the AND gate 25 is at a low level when there is no power failure, the buzzer 10 does not sound unless an abnormal overvoltage and overcurrent occurs.

When a power failure occurs at t 1 in FIG. 3, the pulse train passes through the AND gate 25 and is input to the buzzer 10, so that the buzzer 10 sounds intermittently. When the switch 11 is turned on at time t2, the output line 20a of the flip-flop 20 is inverted to the low level, and the output of the AND gate 23 becomes the low level. Therefore, even if the power failure detection output line 8a is at the high level, the AND The output of the gate 25 goes low and the energization of the buzzer 10 is interrupted.

When the power supply from the inverter 4 starts at t1 in FIG. 3 and the voltage of the storage battery 6 gradually decreases as shown in FIG. 3 (E), and becomes a predetermined level Lr or less at t3, the voltage drop detection circuit. As shown in FIG. 3 (F), a signal indicating a high level voltage drop is generated from 13 and all the outputs of the OR gate 24, AND gate 25 and OR gate 26 become high level, and the buzzer 10 operates as shown in FIG. It is energized as shown in (C), and the voltage drop of the storage battery 6 is notified. The user of the load 3 handles the load 3 in anticipation that the power supply from the inverter 4 will end when an alarm occurs after t3. For example, when the load 3 is a computer system, necessary data is saved.

As is clear from the above, if the voltage drops due to the discharge of the storage battery 6 after a power failure, the buzzer 10 sounds, so that the occurrence of a failure in the load 3 can be prevented. Further, even if the switch 11 is operated to interrupt the energization of the buzzer 10 at the time of power failure, the voltage drop of the storage battery 6 can be known regardless of the interruption. Further, since the buzzer 10 is intermittently energized by the pulse train during the period from t1 to t2, and the buzzer 10 is continuously energized after t3, the two can be distinguished.

[0018]

[Modification]

 The present invention is not limited to the above-mentioned embodiments, and the following modifications are possible, for example. (1) Instead of detecting the remaining charge of the storage battery 6 based on the detection of the voltage drop, measure the power supply time by the inverter 4 or the drive time of the load 3 at the time of a power failure, and when this exceeds the predetermined time, the remaining charge Is less than or equal to a predetermined value, or when the product of the output current of the storage battery 6 or the inverter 4 and the power supply time is greater than or equal to a certain value, the remaining charge can be less than or equal to the predetermined value. (2) Instead of the buzzer 10, a light emitting element or a display can be used as an alarm means. Also, another sounding device can be used instead of the buzzer 10.

[Brief description of drawings]

FIG. 1 is a block diagram showing an uninterruptible power supply according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing the control circuit of FIG. 1 in detail.

FIG. 3 is a diagram showing states of points A to F in FIG.

[Explanation of symbols]

 1 Commercial power supply terminal 6 Storage battery 10 Buzzer 13 Voltage drop detection circuit

Claims (2)

[Scope of utility model registration request] 1. An uninterruptible power supply comprising: a commercial power supply terminal; a storage battery; an inverter connected to the storage battery; and a switch means for selectively connecting the commercial power supply terminal and the inverter to a load. A storage amount detection circuit that detects whether or not the storage amount of the storage battery has decreased to a predetermined value or less due to discharge of the storage battery based on a stop of supply of commercial AC power from the commercial power supply terminal; And an alarm device that issues an alarm in response to a signal indicating detection of the predetermined value or less. 2. An uninterruptible power supply device comprising a commercial power supply terminal, a storage battery, an inverter connected to the storage battery, and switch means for selectively connecting the commercial power supply terminal and the inverter to a load. A power failure detection circuit that detects a stop of commercial AC power supply from the commercial power supply terminal; a power storage amount detection circuit that detects whether or not the power storage amount of the storage battery has become a predetermined value or less; Alarm means for issuing an alarm in response to a signal indicating the detection of a power failure and a signal indicating detection of the storage amount detection circuit or less, and a signal given to the alarm means based on the signal of the power failure detection circuit And an operating means for arbitrarily setting the sending period of the uninterruptible power supply.