JP2022101349A - Uninterruptible power supply - Google Patents

Abstract

To suppress the delayed supply of power to an electric load when power outage occurs.SOLUTION: An uninterruptible power supply 1 includes: a power storage unit 40; a charge control unit 30 which controls to charge the power storage unit 40; a power supply switching unit 20 which supplies an electric load 90 with one of power supplied based on commercial power supply 5 and power output from the power storage part 40; and a controller 50 to which charging information ic related to the charging rate of the power storage part 40 is input. The power supply switching unit 20 supplies the electric load 90 with the power supplied based on the commercial power supply 5 in the case of not being in power outage, and supplies the electric load 90 with power output from the power storage part 40 in the case of being in power outage. In the case of not being in power outage, the controller 50 transmits to the charge control unit 30 instruction signals s1, s2 for starting or stopping charging the power storage unit 40, based on the charging information ic, and when becoming power outage, transmits to the charge control unit 30 an instruction signal s2 which stops charging the power storage part 40.SELECTED DRAWING: Figure 1

Description

The present invention relates to an uninterruptible power supply that supplies power to an electrical load.

Conventionally, an uninterruptible power supply that supplies electric power to an electric load is known. The uninterruptible power supply supplies the power supplied from the commercial power supply to the electric load and charges the battery when there is no power failure, and supplies the electricity already charged to the battery to the electric load when the power failure occurs. (See, for example, Patent Document 1).

Japanese Patent No. 4304624

In the conventional uninterruptible power supply, when a power failure occurs, the electricity charged in the battery is supplied to the electric load. However, for example, when the state of no power failure changes to the state of power failure, the supply of power to the electric load is delayed. , Instantaneous interruptions or voltage drops may occur.

Therefore, an object of the present invention is to provide an uninterruptible power supply capable of suppressing a delay in the supply of electric power to an electric load in the event of a power failure.

The uninterruptible power supply according to one aspect of the present invention is an uninterruptible power supply that supplies electric power to an electric load, and is a power storage device that charges electricity supplied based on a commercial power source and outputs the charged electricity as electric power. A charge control unit provided in a charging path connecting the unit, the commercial power supply, and the power storage unit to control charging of the power storage unit, electric power supplied based on the commercial power supply, and output from the power storage unit. Charging information regarding the charge rate of the power supply switching unit and the power storage unit, which is input with power and supplies either the power supplied based on the commercial power supply or the power output from the power storage unit to the electric load. The power supply switching unit is provided with a controller to which the power is input, and the power supply switching unit supplies the power supplied based on the commercial power supply to the electric load when there is no power failure, and outputs the power from the power storage unit when the power failure occurs. The supplied electric power is supplied to the electric load, and the controller transmits an instruction signal to start or stop charging of the power storage unit based on the charging information to the charging control unit when the power failure is not performed, and the power failure occurs. At that time, an instruction signal for stopping charging of the power storage unit is transmitted to the charge control unit.

In this way, the controller transmits an instruction signal to start or stop charging of the power storage unit based on the charging information to the charge control unit, so that it is possible to prevent the power storage unit from being charged to a charge amount more than necessary. .. As a result, it is possible to increase the chances that the power storage unit can be discharged, and it is possible to suppress the delay in the supply of electric power to the electric load in the event of a power failure.

Further, the power storage unit includes a battery that charges or discharges electricity supplied based on the commercial power source, and a battery management unit that detects the charge rate of the battery, and the battery management unit is the battery. The charging information including the charging rate of the above may be transmitted to the controller.

In this way, the battery management unit transmits the charging information to the controller, so that the controller can control the start or stop of charging of the storage unit based on the charging information. Therefore, it is possible to prevent the power storage unit from being charged to a charge amount more than necessary. As a result, it is possible to increase the chances that the power storage unit can be discharged, and it is possible to suppress the delay in the supply of electric power to the electric load in the event of a power failure.

Further, when the charge control unit shifts from the non-power failure state to the power failure state, the charge path is cut off, and the power supply switching unit outputs from the power storage unit after the charge path is cut off. The generated electric power may be supplied to the electric load.

In this way, the charge control unit cuts off the charging path, so that the electric power output from the power storage unit can be supplied to the electric load after the power storage unit is in a dischargeable state. As a result, it is possible to prevent the power supply to the electric load from being delayed in the event of a power failure.

Further, the uninterruptible power supply further includes a voltage detection unit that detects the voltage of the power supplied based on the commercial power supply, and the voltage detection unit is used when the voltage becomes equal to or less than the first threshold value. A power failure detection signal for detecting the transition to a power failure may be output to the charge control unit, and the charge control unit may cut off the charge path based on the power failure detection signal.

In this way, the charge control unit cuts off the charging path based on the failure detection signal of the voltage detection unit, so that the power output from the power storage unit is transferred to the electric load after the power storage unit is in a dischargeable state. Can be supplied. As a result, it is possible to prevent the power supply to the electric load from being delayed in the event of a power failure.

Further, the power supply switching unit has a second threshold voltage that is lower than the first threshold value, and when the voltage of the power supplied based on the commercial power source becomes the second threshold value, the power supply switching unit is described. The electric power output from the power storage unit may be supplied to the electric load.

In this way, when the voltage of the electric power supplied based on the commercial power source reaches the second threshold value, the electric power output from the power storage unit is supplied to the electric load, so that the charging path is set by the first threshold value. Power can be supplied after it is reliably shut off. As a result, it is possible to prevent the power supply to the electric load from being delayed in the event of a power failure.

Further, the power supply switching unit has a third threshold value which is a value between the first threshold value and the second threshold value, and the voltage of the power supplied based on the commercial power supply is equal to or lower than the second threshold value. When the third threshold value is reached, the electric power supplied based on the commercial power source may be supplied to the electric load.

According to this, it is possible to supply the electric power based on the commercial power source after the electric power is surely restored, and it is possible to supply the stable electric power to the electric load.

Further, the controller has the charging rate and the current charging rate after a predetermined standby time has elapsed after the voltage detected by the voltage detecting unit returns to the first threshold value or higher, or when a power failure occurs. When the difference from the value is equal to or greater than the predetermined value, an instruction signal for starting charging of the power storage unit may be transmitted to the charge control unit.

According to this, even if the power supply from the commercial power source is in an unstable state where power failure and power recovery are repeated in a short time, the charge control unit may malfunction or the battery may be stressed. It can be suppressed.

Further, the non-disruptive power supply device further includes an AC / DC converter that converts an AC voltage supplied from the commercial power source to output a DC voltage, and the AC / DC converter converts the power based on the DC voltage. The electricity supplied to the power supply switching unit and based on the DC voltage may be supplied to the power storage unit via the charge control unit.

According to this, it is possible to output electric power according to an electric load and electric power according to a storage unit by using an AC / DC converter.

The non-disruptive power supply device further includes an AC / DC converter that converts an AC voltage supplied from the commercial power supply to output a DC voltage, and the voltage detection unit is the DC output from the AC / DC converter. The voltage may be detected.

According to this, the charging path can be cut off based on the DC voltage output from the AC / DC converter. As a result, it is possible to appropriately detect the occurrence of a power failure and suppress the delay in the supply of electric power to the electric load.

Further, the electric load may be NAS (Network Attached Storage).

According to this, it is possible to suppress the delay in the supply of electric power to the NAS in the event of a power failure.

It should be noted that these comprehensive or specific embodiments may be realized in a recording medium such as a system, method, integrated circuit, computer program or computer-readable CD-ROM, and the system, method, integrated circuit, computer program. And may be realized by any combination of recording media.

The uninterruptible power supply according to one aspect of the present invention can suppress the delay in the supply of electric power to the electric load in the event of a power failure.

FIG. 1 is a block diagram showing a configuration of an uninterruptible power supply device according to an embodiment. FIG. 2 is a diagram showing a voltage threshold value set in a voltage detection unit and a power supply switching unit of the uninterruptible power supply according to the embodiment. FIG. 3 is a timing chart showing the operation of the uninterruptible power supply device according to the embodiment. FIG. 4 is a flowchart showing charge control of the uninterruptible power supply. FIG. 5 is a block diagram showing a configuration of an uninterruptible power supply device according to a modified example of the embodiment.

A known uninterruptible power supply supplies power supplied from a commercial power source to an electric load and charges the battery when there is no power failure, and when there is a power failure, the electricity already charged in the battery is used as an electric load. Supply to. Charging the battery is controlled by a charging circuit (eg, a charger IC) provided between the commercial power source and the battery. However, in this uninterruptible power supply, for example, if a power failure occurs while charging the battery, the voltage input to the charging circuit is supplied until it drops to the lower limit voltage of the operation of the charging circuit, and the battery is charged during that time. .. Therefore, there may be a time delay between the occurrence of a power failure and the switching of the battery state to discharge to supply power to the electric load.

On the other hand, the uninterruptible power supply according to the embodiment of the present invention has a configuration capable of suppressing a delay in the supply of electric power to an electric load in the event of a power failure.

Hereinafter, embodiments will be specifically described with reference to the drawings.

It should be noted that all of the embodiments described below are comprehensive or specific examples. The numerical values, shapes, materials, components, arrangement positions and connection forms of the components, steps, the order of steps, etc. shown in the following embodiments are examples, and are not intended to limit the scope of claims. Further, among the components in the following embodiments, the components not described in the independent claim indicating the highest level concept are described as arbitrary components. In addition, each figure is not necessarily exactly illustrated. In each figure, substantially the same configuration is designated by the same reference numerals, and duplicate explanations are omitted or simplified.

(Embodiment)
[Uninterruptible power supply configuration]
An uninterruptible power supply (UPS: Uninterruptible Power Supply) according to an embodiment will be described.

FIG. 1 is a block diagram showing a configuration of an uninterruptible power supply device 1 according to an embodiment.

As shown in FIG. 1, the uninterruptible power supply device 1 includes a power supply switching unit 20, a charge control unit 30, a power storage unit 40, a controller 50, and a voltage detection unit 60. Further, the uninterruptible power supply device 1 includes an AC / DC converter 10 and a DC / DC converter 70.

In addition to the uninterruptible power supply 1, FIG. 1 also shows a commercial power supply 5 and an electric load 90. Further, FIG. 1 shows a first power supply path r1 connecting the commercial power supply 5 and the electric load 90, a second power supply path r2 connecting the power storage unit 40 and the electric load 90, and the commercial power supply 5 and the power storage unit 40. The charging path rc to connect is also shown.

The AC / DC converter 10 is a circuit that converts an AC voltage supplied from a commercial power source 5 into a DC voltage and outputs it. For example, the AC / DC converter 10 converts an AC voltage of 100V or 200V into a DC voltage of 12V and outputs it. The AC / DC converter 10 has an input side connected to a commercial power source 5, and an output side connected to a power supply switching unit 20, a charge control unit 30, and a voltage detection unit 60. The AC / DC converter 10 supplies electric power based on the DC voltage to the power supply switching unit 20, and supplies electric power (electricity) based on the DC voltage to the power storage unit 40 via the charge control unit 30. The AC / DC converter 10 may be provided outside the uninterruptible power supply device 1 and between the commercial power supply 5 and the uninterruptible power supply device 1.

The charge control unit 30 is provided on the charging path rc connecting the commercial power source 5 and the power storage unit 40, and controls the charging of the power storage unit 40. The charge control unit 30 is composed of, for example, a charger IC 31 and an open / close switch 32 connected in series. In this example, the charger IC 31 is arranged between the AC / DC converter 10 and the power storage unit 40, and the open / close switch 32 is arranged between the charger IC 31 and the power storage unit 40. Each of the charger IC 31 and the open / close switch 32 can be driven by using the electric power supplied from the AC / DC converter 10 as a drive source. The open / close switch 32 may be built in the charger IC 31.

The charger IC 31 is a circuit that converts a DC voltage output from the AC / DC converter 10 into a voltage and a current suitable for charging by the storage unit 40, and is, for example, a DC / DC converter. The charger IC 31 is connected to the controller 50, and based on a command transmitted from the controller 50, starts or stops charging of the power storage unit 40 and controls the voltage, current, and the like of electricity to be charged.

The open / close switch 32 is a switch that puts the charging path rc in a cutoff state or a conduction state, and is, for example, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The open / close switch 32 is connected to the voltage detection unit 60 and the controller 50 via a signal line. The open / close switch 32 cuts off or conducts the charging path rc based on the power failure detection signal sb output from the voltage detection unit 60, the instruction signal s1 for starting charging and the instruction signal s2 for stopping charging transmitted from the controller 50. do.

The power storage unit 40 charges the electricity supplied based on the commercial power source 5, that is, the electricity output from the AC / DC converter 10, when there is no power failure (when the commercial power source 5 does not have a power failure). Further, the power storage unit 40 outputs the already charged electricity as electric power when a power failure occurs (when the commercial power source 5 fails). The power storage unit 40 is connected to the AC / DC converter 10 via the charging path rc, and is connected to the power supply switching unit 20 via the second power feeding path r2. The power storage unit 40 has a battery 41 and a battery management unit 42.

The battery 41 is a secondary battery that charges or discharges electricity supplied based on the commercial power source 5, that is, electricity output from the AC / DC converter 10. The battery 41 is, for example, a lithium ion battery composed of a plurality of battery cells. Since the lithium ion battery has low resistance to overcharging, appropriate charging using the charge control unit 30 is executed. The battery 41 is charged when there is no power failure, but when the charging rate exceeds a predetermined charging rate, the battery 41 is not charged and is in a self-discharged state. The self-discharge state is a state in which the battery is not yet connected to the electric load 90, but can be discharged and output power as soon as it is connected to the electric load 90, for example.

The battery management unit 42 is a circuit that manages the charging state of the battery 41 and the like. The battery management unit 42 is communicatively connected to the controller 50 by the system management bus (SMBus). The battery management unit 42 detects the charge information ic regarding the charge rate (SOC: System of Charge) of the battery 41. Further, the battery management unit 42 transmits the detected charge information ic to the controller 50 at regular time intervals, for example, every 10 seconds. The charging information ic includes the internal temperature of the battery 41, the voltage value of the battery 41, the current value passing through the input / output terminals of the battery 41, the estimated remaining battery level, the estimated battery full charge capacity, the number of charge / discharge cycles, and the like. May contain information about.

The voltage detection unit 60 is a circuit that detects the voltage of the power supplied based on the commercial power source 5, in other words, a circuit that detects the voltage of the power supplied to each of the power supply switching unit 20 and the power storage unit 40. .. For example, the voltage detection unit 60 is connected to the output side of the AC / DC converter 10 and detects the output voltage of the AC / DC converter 10. The voltage detection unit 60 may be built in the charge control unit 30.

The voltage detection unit 60 is connected to the open / close switch 32 of the charge control unit 30 and the controller 50 via a signal line. The voltage detection unit 60 is set with a first threshold value Vth1, which is a voltage for detecting the transition to a power failure. The first threshold value Vth1 is a value lower than the specified voltage output from the AC / DC converter 10, and is, for example, 11V. When the detected voltage becomes equal to or less than the first threshold value Vth1, the voltage detection unit 60 outputs a power failure detection signal sb for detecting the transition to a power failure to the open / close switch 32 and the controller 50. For example, the voltage detection unit 60 outputs a Hi level power failure detection signal sb when the detected voltage exceeds the first threshold value Vth1, and the Low level power failure detection signal sb when the detected voltage is equal to or less than the first threshold value Vth1. Is output (see Fig. 3).

The controller 50 is a circuit that controls the operation of the power storage unit 40 and the charge control unit 30, and is connected to the power storage unit 40, the charge control unit 30, and the voltage detection unit 60 via a signal line. Further, the controller 50 is also connected to the electric load 90 via a signal line (not shown). The controller 50 acquires the charge information ic including the charge rate from the power storage unit 40, and when there is no power failure, the controller 50 receives the instruction signal s1 for starting charging or the instruction signal s2 for stopping charging based on the charge information ic. Send to 30. For example, the controller 50 operates the charge control unit 30 to charge the battery 41 so that the battery 41 has a capacity that can safely back up the electric load 90. On the other hand, the controller 50 performs charge control so that the battery 41 is not charged to a charge amount more than necessary and the battery 41 is not overcharged.

Further, when a power failure occurs, the controller 50 transmits an instruction signal s2 for stopping charging to the charge control unit 30 based on the power failure detection signal sb output from the voltage detection unit 60. The controller 50 may send a shutdown command to the electric load 90 in order to safely shut down the electric load 90 when the remaining amount of the battery 41 becomes low in the scene of a power failure.

The power supply switching unit 20 is provided on the first power supply path r1 connecting the commercial power source 5 and the electric load 90, and on the second power supply path r2 connecting the power storage unit 40 and the electric load 90. The power supplied based on the commercial power source 5 and the power output from the power storage unit 40 are input to the power supply switching unit 20.

The power supply switching unit 20 has, for example, a plurality of load switches using MOSFETs, and by exclusively opening and closing the plurality of load switches, the power supply path to the electric load 90 is set to the first power supply path r1. Alternatively, the second power supply path r2 is switched to either one. That is, the power supply switching unit 20 supplies either the power supplied based on the commercial power source 5 or the power output from the power storage unit 40 to the electric load 90. For example, the power supply switching unit 20 supplies the power supplied based on the commercial power source 5 to the electric load 90 when there is no power failure, and the power output from the power storage unit 40 to the electric load 90 when there is a power failure. Supply. The power supply switching unit 20 can be driven by using the power output from the AC / DC converter 10 or the power storage unit 40 as a drive source.

The DC / DC converter 70 is provided on a path connecting the power supply switching unit 20 and the electric load 90. In FIG. 1, each of the first power supply path r1 and the second power supply path r2 is shown as a path between the power supply switching unit 20 and the electric load 90, and the first power supply path r1 and the second power supply path r2 between them are shown. The power supply path r2 is the same power supply line. The DC / DC converter 70 outputs one of the electric power supplied from the AC / DC converter 10 and the power storage unit 40 by stepping down or boosting the voltage according to the voltage corresponding to the electric load 90. The electric power (DC voltage) output from the DC / DC converter 70 is input to the electric load 90. The electric power output from the DC / DC converter 70 is also used to drive the controller 50.

The electric load 90 is, for example, a PC (personal computer) or a network server. The electric load 90 may be NAS (Network Attached Storage). In FIG. 1, the electric load 90 is connected to the uninterruptible power supply 1, but the electric load is not limited to that, and the electric load may be an electric device including the uninterruptible power supply 1.

In the present embodiment, the controller 50 transmits instruction signals s1 and s2 for starting or stopping charging of the power storage unit 40 to the charge control unit 30 based on the charge information ic. Therefore, it is possible to prevent the power storage unit 40 from being charged to a charge amount more than necessary. As a result, it is possible to increase the chances that the power storage unit 40 can be discharged, and it is possible to suppress the delay in the supply of electric power to the electric load 90 in the event of a power failure. Further, since it is possible to prevent the power storage unit 40 from being charged to a charge amount more than necessary, it is possible to prevent the power storage unit 40 from being overcharged and deteriorated.

Further, in the uninterruptible power supply 1, the charge control unit 30 cuts off the charging path rc based on the power failure detection signal sb. According to this, after the charging path rc is cut off and the power storage unit 40 is in a state where it can be discharged, the electric power output from the power storage unit 40 can be supplied to the electric load 90. As a result, it is possible to prevent the power supply to the electric load from being delayed in the event of a power failure.

[Setting of voltage detection unit and power supply switching unit]
Here, an example of setting of the voltage detection unit 60 and the power supply switching unit 20 will be described.

FIG. 2 is a diagram showing threshold values of voltages set in the voltage detection unit 60 and the power supply switching unit 20 of the uninterruptible power supply 1. FIG. 2 shows the first threshold value Vth1, the second threshold value Vth2, and the third threshold value Vth3 as the threshold values to be set.

The voltage detection unit 60 is set with a first threshold value Vth1, which is a voltage indicating a transition from a non-power failure state to a power failure state. Further, a second threshold value Vth2, which is a voltage lower than the first threshold value Vth1, is set in the power supply switching unit 20. The second threshold value Vth2 is a voltage indicating that the power failure transition period T12 has ended and the power failure period T2 has started. Further, the power supply switching unit 20 is set with a third threshold value Vth3, which is a value between the first threshold value Vth1 and the second threshold value Vth2.

Here, when the voltage output from the AC / DC converter 10 is used as the specified voltage when there is no power failure, each threshold value has a relationship of specified voltage> first threshold value Vth1> third threshold value Vth3> second threshold value Vth2. Have. In this example, the specification voltage is 12V, the first threshold value is Vth1 = 11V, the second threshold value is Vth2 = 10V, and the third threshold value is Vth3 = 10.5V.

The first threshold value Vth1 is set based on the drop in the specified voltage at the maximum load of the electric load 90. The third threshold value Vth3 has the first threshold value Vth1 and the second threshold value Vth3 in order to give hysteresis to the change in the voltage output from the AC / DC converter 10 from the start of the power failure period T2 to the recovery of power and the return to the normal period T1. It is set to a value between the threshold value Vth2 and the threshold value Vth2. Further, the difference between the thresholds is appropriately set based on the degree of bluntness of the waveform of the voltage output from the AC / DC converter 10, the responsiveness of the voltage detection unit 60, the switchover time of the power supply switching unit 20, and the like. Will be done. The setting of the second threshold value Vth2 and the third threshold value Vth3 is realized, for example, by adding a comparator circuit corresponding to the threshold value to the load switch of the power supply switching unit 20.

Under the settings of the voltage detection unit 60 and the power supply switching unit 20 shown above, the operation of the uninterruptible power supply 1 shown below is executed.

[Operation of uninterruptible power supply]
Next, the operation of the uninterruptible power supply device 1 according to the embodiment will be described in chronological order. Here, a scene in which a power failure occurs while charging the power storage unit 40 will be described.

FIG. 3 is a timing chart showing the operation of the uninterruptible power supply device 1. In FIG. 3A, a normal period T1 which is a non-power failure period, a power failure transition period T12 which is a period of transition from a non-power failure state to a power failure state, and a power failure period which is a power failure period are shown. The period T2 is shown.

First, the operation of the uninterruptible power supply device 1 during the normal period T1 will be described. In the normal period T1, the voltage output from the AC / DC converter 10 is supplied to each of the electric load 90 and the power storage unit 40. The voltage output from the AC / DC converter 10 is 12V, which is the specified voltage. Electric power is supplied to the electric load 90 via the first power supply path r1. The electricity storage unit 40 is charged with electricity output from the AC / DC converter 10 by the charge control of the charge control unit 30.

Next, the operation of the uninterruptible power supply 1 during the power failure transition period T12 and the power failure period T2 will be described. When an abnormality occurs in the commercial power supply 5, the voltage output from the AC / DC converter 10 drops from 12V as shown in FIG. 3B. When the voltage drops and the output voltage of the AC / DC converter 10 reaches the first threshold value Vth1 = 11V, the power failure transition period T12 starts. In the power failure transition period T12, as shown in FIG. 3C, the power failure detection signal sb output from the voltage detection unit 60 changes from the Hi level to the Low level. By this power failure detection signal sb, the open / close switch 32 of the charge control unit 30 is opened, and the charge path rc is cut off. Due to the interruption of the charging path rc, electricity is not supplied to the power storage unit 40. As a result, the battery 41 changes from the charged state to the self-discharged state as shown in FIG. 3D. The voltage of the battery 41 changes from the charge voltage to a voltage equivalent to self-discharge.

Further, as shown in FIG. 3B, when the voltage output from the AC / DC converter 10 drops from 11V to the second threshold value Vth2 = 10V, the power failure transition period T12 ends and the power failure period T2 is reached. come in. In the power failure period T2, the path for supplying electric power to the electric load 90 is switched to the second power supply path r2 by the operation of the electric power supply switching unit 20. As a result, as shown in FIGS. 3 (d) and 3 (e), the battery 41 starts discharging the electric load 90, that is, supplying electric power. The voltage of the battery 41 becomes a voltage corresponding to the load of the electric load 90.

In the power failure transition period T12, a voltage drop occurs in the output voltage of the power supply switching unit 20, but the low voltage dropped is adjusted by the DC / DC converter 70 and is output as a stable voltage (FIG. 3). (F)). Further, in the power failure period T2, since the voltage output from the battery 41 is higher than the specified voltage, a high voltage is also output from the power supply switching unit 20, but this high voltage is adjusted by the DC / DC converter 70. It is output as a stable voltage.

Next, the operation of the uninterruptible power supply device 1 when the power failure period T2 changes to the normal period T1 will be described. When the commercial power supply 5 is restored, as shown in FIG. 3B, the voltage output from the AC / DC converter 10 rises toward the specified voltage of 12V. Then, when the output voltage of the AC / DC converter 10 reaches the third threshold value Vth3 = 10.5V, the normal period returns to T1. In the normal period T1, the path for supplying electric power to the electric load 90 is switched to the first power supply path r1 by the operation of the electric power supply switching unit 20. As a result, the electric power output from the AC / DC converter 10 is supplied to the electric load 90.

On the other hand, in the normal period T1, the electric storage unit 40 does not discharge to the electric load 90, so that the voltage of the battery 41 changes to a voltage equivalent to self-discharge as shown in FIG. 3D. When the voltage output from the AC / DC converter 10 rises and the voltage detected by the voltage detection unit 60 reaches the first threshold Vth1, as shown in FIGS. 3 (b) and 3 (c), the power failure detection signal sb Changes from Low level to Hi level. As a result, the open / close switch 32 is closed and the charging path rc becomes conductive.

As described above, the power supply switching unit 20 supplies the electric power supplied based on the commercial power source 5 to the electric load 90 via the first power supply path r1 when there is no power failure. The voltage detection unit 60 outputs a power failure detection signal sb to the charge control unit 30 when the voltage of the power supplied based on the commercial power source 5 reaches the first threshold value Vth1. The charge control unit 30 cuts off the charge path rc based on the power failure detection signal sb. The power supply switching unit 20 stores electricity via the second power supply path r2 when a power failure occurs, that is, when the voltage of the power supplied based on the commercial power source 5 changes from the specified voltage to the second threshold voltage Vth2. The electric power output from the unit 40 is supplied to the electric load 90. Further, the power supply switching unit 20 is the third when the power is restored, that is, when the voltage of the power supplied based on the commercial power source 5 becomes the second threshold Vth2 or less and then becomes the third threshold Vth3. 1 The electric power supplied based on the commercial power source 5 is supplied to the electric load 90 via the power supply path r1.

In the controller 50, after a predetermined standby time tw has elapsed after the voltage detected by the voltage detection unit 60 returns to the first threshold value Vth1 or higher (see (c) in FIG. 3), or when a power failure occurs. When the difference between the charging rate and the current charging rate is equal to or greater than the default value (%), the instruction signal s1 for starting charging of the power storage unit 40 may be transmitted to the charging control unit 30. When the instruction signal s1 for starting charging is input to the charge control unit 30, charging in the power storage unit 40 is restarted.

For example, in the above, the predetermined waiting time tw is 10 seconds, and the default value is 5%. If the power supply by the commercial power source 5 is in an unstable state in which a power failure and a power recovery are repeated in a short time, a problem may occur in the charging operation. By confirming that the difference in charge rate is equal to or greater than the default value, it is possible to prevent the charge control unit 30 from malfunctioning or stressing the battery 41.

[Charge control of uninterruptible power supply]
Next, the charge control of the uninterruptible power supply device 1 will be described. The charge control of the uninterruptible power supply 1 is executed, for example, so that the battery 41 is not charged to a charge amount more than necessary and the safety of the electric load 90 is ensured.

FIG. 4 is a flowchart showing charge control of the uninterruptible power supply 1.

First, electric power is supplied from the commercial power source 5, and the uninterruptible power supply device 1 is activated (step S11). The controller 50 starts charge control by float charge or trickle charge.

Next, the controller 50 determines whether or not the charge rate of the battery 41 is less than a predetermined value based on the charge information ic acquired from the power storage unit 40 (step S12). The predetermined value of the charge rate used in the determination in step S12 is, for example, 75%.

When the charge rate of the battery 41 is not less than a predetermined value (No in S12), the charge amount of the battery 41 is considered to be sufficient, and the battery 41 is not charged more than necessary. Next, the controller 50 determines whether or not the power supply from the commercial power source 5 is cut off and a power failure occurs (step S21). If it is determined that there is no power failure in the state where the battery 41 is not being charged (No in S21), the process returns to step S12, and it is continuously determined whether or not the charge rate of the battery 41 is less than the predetermined value. If it is determined that a power failure has occurred (Yes in S21), step S16, which will be described later, is executed.

On the other hand, when the charge rate of the battery 41 is less than a predetermined value in step S12 (Yes in S12), the controller 50 transmits an instruction signal s1 instructing the charge control unit 30 to start charging (step S13). .. The charge control unit 30 starts charging the power storage unit 40, and the power storage unit 40 is charging.

Next, the controller 50 determines whether or not a power failure has occurred while charging the power storage unit 40 (step S14). Specifically, it is determined whether or not the power failure detection signal sb of the voltage detection unit 60 has changed to a signal level indicating a power failure.

When it is determined that there is no power failure (No in S14), the controller 50 further determines whether or not the charge rate of the battery 41 has reached the charge completion value at which charging should be completed (step S25). ). The charging completion value is, for example, 80%, which is higher than the predetermined value of the charging rate in step S12. If the charging rate has not reached the charging completion value (No in S25), the process returns to step S14 in order to continuously monitor the presence or absence of a power failure. On the other hand, when the charging rate has reached the charging completion value (Yes in S25), the controller 50 transmits an instruction signal s2 instructing the charging control unit 30 to stop charging (step S26). The charge control unit 30 stops charging the power storage unit 40, and the power storage unit 40 is in a state of stop charging. The controller 50 returns to step S12 and continues to monitor the charge rate of the battery 41.

If it is determined in step S14 that a power failure has occurred (Yes in S14), the controller 50 transmits an instruction signal s2 to stop charging to the charge control unit 30 (step S15). In this example, when the power failure detection signal sb changes to a signal level indicating a power failure, the charge path rc of the power storage unit 40 is cut off by the open / close switch 32. Therefore, there may be a certain time delay between the transmission of the instruction signal s2 for stopping charging by the controller 50 and the stopping of the charging operation by the charging control unit 30.

Since the discharge state of the power storage unit 40 continues in the event of a power failure, the controller 50 determines whether or not the charge rate of the battery 41 is at a value that can safely back up the electric load 90 (step S16). The value that can safely back up the electric load 90 is, for example, 25%, which is 1/4 of the full charge capacity of the battery 41. Here, when the charge rate of the battery 41 is not a value that can safely back up the electric load 90 (No in S16), the controller 50 transmits a shutdown command to the electric load 90 (step S31). .. After the shutdown of the electric load 90 is completed, the controller 50 goes into a power-off or sleep state (step S32).

On the other hand, when the charge rate of the battery 41 is at a value that can safely back up the electric load 90 (Yes in S16), the controller 50 further recovers the power supplied from the commercial power source 5 from the power failure state. It is determined whether or not the state of electricity has been restored (step S17). Specifically, it is determined whether or not the power failure detection signal sb of the voltage detection unit 60 has changed to a signal level indicating a state in which no power failure has occurred. When the controller 50 determines that the power recovery state has not been restored (No in S17), the controller 50 returns to step S16. On the other hand, when the controller 50 determines that the power recovery state has been restored (Yes in S17), the controller 50 further executes the determination in step S18. In step S18, the controller 50 determines whether or not a predetermined standby time tw has elapsed since the voltage detected by the voltage detection unit 60 returned to the first threshold value Vth1 or higher, or the charge rate of the battery 41 when a power failure occurs. It is determined whether or not the difference from the charge rate of the current battery 41 is equal to or greater than the default value (step S18).

In step S18, when the predetermined waiting time tw has not elapsed and the difference in the charging rates is not equal to or more than the default value (No in S18), the step is taken until the determination in step S18 becomes Yes. The judgment of S18 is repeated. In step S18, when the predetermined waiting time tw has elapsed, or when the difference in the charging rates is equal to or greater than the default value (Yes in S18), the process returns to step S12. Then, in step S12, when the charge rate of the battery 41 is less than a predetermined value (Yes in S12), the charge control unit 30 starts charging the power storage unit 40, and the power storage unit 40 is charging. ..

According to the charge control by the uninterruptible power supply device 1, it is possible to prevent the power storage unit 40 from being charged to a charge amount more than necessary. As a result, it is possible to increase the chances that the power storage unit 40 can be discharged, and it is possible to suppress the delay in the supply of electric power to the electric load 90 in the event of a power failure. In addition, the power storage unit 40 can be appropriately charged, and deterioration of the power storage unit 40 can be suppressed. In addition, it is possible to prevent the charging operation of the power storage unit 40 from becoming unstable after a power failure. Further, when the charge rate of the battery 41 reaches a value at which the electric load 90 cannot be safely backed up, the electric load 90 can be safely shut down.

[Modified example of the embodiment]
The uninterruptible power supply 1A according to the modified example of the embodiment will be described. In the modified example, an example in which the uninterruptible power supply 1A further includes a DC / AC inverter 80 will be described.

FIG. 5 is a block diagram showing the configuration of the uninterruptible power supply device 1A according to the modified example.

As shown in FIG. 5, the uninterruptible power supply 1A includes a power supply switching unit 20, a charge control unit 30, a power storage unit 40, a controller 50, and a voltage detection unit 60. Further, the uninterruptible power supply 1A includes an AC / DC converter 10 and a DC / DC converter 70, and further includes a DC / AC inverter 80.

The DC / AC inverter 80 is provided on a path connecting the power supply switching unit 20 and the electric load 90A. FIG. 5 shows a first power supply path r1 and a second power supply path r2 as a path between the power supply switching unit 20 and the electric load 90A, and the first power supply path r1 and the second power supply path between them are shown. r2 is actually the same power supply line. The DC / AC inverter 80 converts one of the electric powers supplied from the AC / DC converter 10 and the power storage unit 40 into alternating current according to the voltage and frequency corresponding to the electric load 90A, and outputs the alternating current. The electric power (AC voltage) output from the DC / AC inverter 80 is input to the electric load 90A.

[Effects, etc.]
As described above, according to the uninterruptible power supply 1 according to one aspect of the present invention, the controller 50 sets the instruction signals s1 and s2 for starting or stopping the charging of the power storage unit 40 based on the charge information ic to the charge control unit. By transmitting to 30, it is possible to prevent the power storage unit 40 from being charged to a charge amount more than necessary. As a result, it is possible to increase the chances that the power storage unit 40 can be discharged, and it is possible to suppress the delay in the supply of electric power to the electric load 90 in the event of a power failure.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, the battery management unit 42 transmits the charge information ic to the controller 50, so that the controller 50 charges the power storage unit 40 based on the charge information ic. Can be controlled to start or stop. Therefore, it is possible to prevent the power storage unit 40 from being charged to a charge amount more than necessary. As a result, it is possible to increase the chances that the power storage unit 40 can be discharged, and it is possible to suppress the delay in the supply of electric power to the electric load 90 in the event of a power failure.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, the charge control unit 30 cuts off the charging path rc, so that the power storage unit 40 is in a dischargeable state, and then the power storage unit 40 outputs the power. The generated power can be supplied to the electric load 90. As a result, it is possible to prevent the power supply to the electric load 90 from being delayed in the event of a power failure.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, the charge control unit 30 shuts off the charging path rc based on the power failure detection signal sb of the voltage detection unit 60, so that the power storage unit 40 is discharged. After the possible state, the electric power output from the power storage unit 40 can be supplied to the electric load 90. As a result, it is possible to prevent the power supply to the electric load 90 from being delayed in the event of a power failure.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, the power output from the power storage unit 40 is used when the voltage of the power supplied based on the commercial power supply 5 reaches the second threshold voltage Vth2. By supplying the electric load 90, the electric power can be supplied after the charging path rc is surely cut off by the first threshold voltage Vth1. As a result, it is possible to prevent the power supply to the electric load 90 from being delayed in the event of a power failure.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, it is possible to supply power based on the commercial power supply 5 after the power is reliably restored, and stable power is supplied to the electric load 90. Can be done.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, even if the power supply by the commercial power supply 5 is in an unstable state in which a power failure and a power recovery are repeated in a short time, the charge control unit is used. It is possible to prevent the 30 from malfunctioning and the battery 41 from being stressed.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, the AC / DC converter 10 can be used to output electric power corresponding to the electric load 90 and electric power corresponding to the power storage unit 40. ..

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, the charging path rc can be cut off based on the voltage of the electric power output from the AC / DC converter 10. As a result, it is possible to appropriately detect the occurrence of a power failure and suppress the delay in the supply of electric power to the electric load 90.

Further, according to the uninterruptible power supply 1 according to one aspect of the present invention, it is possible to suppress the delay in the supply of electric power to the NAS in the event of a power failure.

(Other embodiments)
Although the uninterruptible power supply device according to one or more aspects of the present invention has been described above based on the embodiments and the like, the present invention is not limited to the embodiments and the like. As long as it does not deviate from the gist of the present invention, one or more of the present embodiments may be modified by those skilled in the art, or may be constructed by combining components in different embodiments. It may be included within the scope of the embodiment.

The present invention can be widely used in a network server provided with an uninterruptible power supply.

1, 1A Uninterruptible power supply 5 Commercial power supply 10 AC / DC converter 20 Power supply switching unit 30 Charge control unit 31 Charger IC
32 Open / close switch 40 Power storage unit 41 Battery 42 Battery management unit 50 Controller 60 Voltage detection unit 70 DC / DC converter 80 DC / AC inverter 90, 90A Electric load ic Charging information r1 1st power supply path r2 2nd power supply path rc Charging path s1 , S2 Instruction signal sb Power failure detection signal T1 Normal period T2 Power failure period T12 Power failure transition period tw Standby time Vth1 1st threshold Vth2 2nd threshold Vth3 3rd threshold

Claims (10)

An uninterruptible power supply that supplies power to an electrical load
A power storage unit that charges electricity supplied based on commercial power and outputs the charged electricity as electric power.
A charge control unit provided in a charging path connecting the commercial power source and the power storage unit to control charging of the power storage unit,
The electric power supplied based on the commercial power source and the electric power output from the electric storage unit are input, and either the electric power supplied based on the commercial power source or the electric power output from the electric storage unit is used as the electric load. Power supply switching unit to supply to
A controller for inputting charging information regarding the charging rate of the power storage unit, and
Equipped with
The power supply switching unit supplies the electric power supplied based on the commercial power source to the electric load when there is no power failure, and supplies the electric power output from the power storage unit to the electric load when the power failure occurs. ,
The controller transmits an instruction signal to start or stop charging of the power storage unit based on the charging information when the power failure occurs, and charges the power storage unit when the power failure occurs. Sending an instruction signal to stop to the charge control unit,
Uninterruptible power system. The power storage unit includes a battery that charges or discharges electricity supplied based on the commercial power source, a battery management unit that detects the charge rate of the battery, and a battery management unit.
Have,
The battery management unit transmits the charging information including the charging rate of the battery to the controller.
The uninterruptible power supply according to claim 1. The charge control unit cuts off the charging path when shifting from the non-power failure state to the power failure state.
The power supply switching unit supplies the power output from the power storage unit to the electric load after the charging path is cut off.
The uninterruptible power supply according to claim 1 or 2. Further, it is provided with a voltage detection unit that detects the voltage of the electric power supplied based on the commercial power supply.
The voltage detection unit outputs a power failure detection signal for detecting the transition to the power failure to the charge control unit when the voltage becomes equal to or lower than the first threshold value.
The charge control unit cuts off the charge path based on the power failure detection signal.
The uninterruptible power supply according to claim 3. The power supply switching unit has a second threshold voltage that is lower than the first threshold value, and when the voltage of the power supplied based on the commercial power source reaches the second threshold value, the power storage unit Supplying the electric power output from the electric load to the electric load,
The uninterruptible power supply according to claim 4. The power supply switching unit has a third threshold value that is a value between the first threshold value and the second threshold value, and the voltage of the power supplied based on the commercial power source becomes equal to or lower than the second threshold value. Then, when the third threshold is reached, the electric power supplied based on the commercial power source is supplied to the electric load.
The uninterruptible power supply according to claim 5. The controller has the charging rate and the current charging rate after a predetermined standby time has elapsed after the voltage detected by the voltage detecting unit returns to the first threshold value or higher, or when a power failure occurs. When the difference is equal to or greater than a predetermined value, an instruction signal for starting charging of the power storage unit is transmitted to the charge control unit.
The uninterruptible power supply according to claim 6. Further, it is equipped with an AC / DC converter that converts the AC voltage supplied from the commercial power source and outputs the DC voltage.
The AC / DC converter supplies the power based on the DC voltage to the power supply switching unit, and supplies the electricity based on the DC voltage to the power storage unit via the charge control unit. The uninterruptible power supply according to any one of 1 to 7. Further, it is equipped with an AC / DC converter that converts the AC voltage supplied from the commercial power source and outputs the DC voltage.
The uninterruptible power supply according to any one of claims 4 to 7, wherein the voltage detection unit detects the DC voltage output from the AC / DC converter. The electric load is NAS (Network Attached Storage).
The uninterruptible power supply according to any one of claims 1 to 9.

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