JP2010016995A - Uninterruptible power supply unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an uninterruptible power supply unit capable of prolonging the service life of a storage battery even when instantaneous power failure and instantaneous voltage drop of an AC power supply occur frequently. <P>SOLUTION: The uninterruptible power supply unit has: a spare uninterruptible power supply section 3 connected to an AC power supply and a storage battery 11, outputting first AC power based on a switching signal and charging and discharging the storage battery; and a usual uninterruptible power supply section 1 connected to the AC power supply, the output side of the spare uninterruptible power supply section and an electric double layer capacitor 9, supplying second AC power to a load and charging and discharging the electric double layer capacitor. When instantaneous power failure and instantaneous voltage drop occur in the AC power supply, the usual uninterruptible power supply section discharges the electric dual layer capacitor to supply the second AC power to the load, and transmits a discharge pre-completion signal as a switching signal to the spare uninterruptible power supply section when the both end voltage of the electric double layer capacitor becomes not more than a predetermined value, and the spare uninterruptible power supply section discharges the storage battery based on the discharge pre-completion signal to supply the first AC power to the usual uninterruptible power supply section. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an uninterruptible power supply.

  An uninterruptible power supply (UPS) converts alternating current of alternating current power into direct current with an AC-DC converter, converts it into desired alternating current with a DC-AC converter, and supplies it to a load such as a computer. The uninterruptible power supply supplies a stable AC power from a DC-AC converter to a load using a lead-acid battery (hereinafter abbreviated as a storage battery) as a DC input source when the voltage of the AC power supply is reduced or during a power failure. .

  In addition, as an uninterruptible power supply, there is also a regular standby uninterruptible power supply that supplies an uninterruptible power supply from the standby uninterruptible power supply when the normal uninterruptible power supply is inspected or malfunctioned. An example of the apparatus is shown (Patent Document 1).

  This uninterruptible power supply device has a regular uninterruptible power supply unit 101A and a standby uninterruptible power supply unit 101B, each of the regular uninterruptible power supply unit 101A and the standby uninterruptible power supply unit 101B has a storage battery, At the time of instantaneous voltage drop of AC power supply or power failure, DC power from the storage battery is converted to AC power and supplied to the load.

  Then, in a state where the common uninterruptible power supply unit 101A is supplying a load, the standby uninterruptible power supply unit 101B stands by in an unloaded operation by the bypass power supply 114, and the AC-DC converter 105 and the DC-AC converter 106 are stopped. is doing.

On the other hand, when the common uninterruptible power supply unit 101A fails, when the standby uninterruptible power supply unit 101B receives a failure signal from the regular uninterruptible power supply unit 101A, the load is supplied to the load by the bypass power supply 114 using the AC power supply. The stopped AC-DC converter 105 and DC-AC converter 106 are automatically operated to automatically switch from the bypass power supply 114 to the UPS power supply 113 and supply the load 116 with the UPS power supply 113.
JP 2003-87798 A

  However, since the uninterruptible power supply of Patent Document 1 uses a storage battery, if frequent backup is performed in the case of an instantaneous power failure or instantaneous voltage drop of an AC power supply, the storage battery is repeatedly charged and discharged, and the storage battery Life is shortened. In addition, the storage battery normally has an allowable temperature of approximately 40 ° C., but its life becomes shorter as the ambient temperature increases.

  An object of the present invention is to provide an uninterruptible power supply capable of extending the life of a storage battery even during frequent instantaneous blackouts and instantaneous voltage drops of an AC power supply.

  In order to solve the above-mentioned problem, the invention of claim 1 is a standby battery that is connected to a storage battery, an AC power source, and the storage battery, outputs a first AC power based on a switching signal, and charges and discharges the storage battery. A power failure power supply unit, an electric double layer capacitor, the AC power source, an output side of the backup uninterruptible power supply unit and the electric double layer capacitor are connected to supply a second AC power to the load and the electric double layer capacitor A normal uninterruptible power supply unit that performs charging and discharging of the battery, and the normal uninterruptible power supply unit discharges the electric double layer capacitor when the AC power supply is instantaneously interrupted and when the instantaneous voltage drops. When the second AC power is supplied to the load, and the voltage across the electric double layer capacitor becomes equal to or lower than a specified value before the end of discharge, the pre-discharge end signal is used as the switching signal. The standby uninterruptible power supply unit supplies the first AC power to the regular uninterruptible power supply unit by discharging the storage battery based on the pre-discharge signal. To do.

  According to a second aspect of the present invention, in the uninterruptible power supply according to the first aspect, the common uninterruptible power supply unit is configured to connect the electric double layer capacitor when the AC power is restored and when the voltage drop is recovered. The charging is performed, and when the charging of the electric double layer capacitor is substantially completed, a charging completion signal is sent to the standby uninterruptible power supply unit as the switching signal.

  According to the present invention, during an instantaneous power failure and an instantaneous voltage drop of the AC power supply, AC power is supplied to the load by a discharge operation by the electric double layer capacitor connected to the normal uninterruptible power supply, and the voltage across the electric double layer capacitor is When the voltage becomes equal to or lower than the predetermined discharge end voltage, the AC power is continuously supplied to the load by the discharging operation by the storage battery connected to the standby uninterruptible power supply. Thereby, only when the power failure time of the AC power source becomes longer and when the voltage drop time becomes longer, the AC power is supplied to the load by the discharging operation by the storage battery instead of the discharging operation by the electric double layer capacitor. For this reason, even in the case of frequent instantaneous power failures and instantaneous voltage drops of the AC power supply, the storage battery does not repeat charging and discharging frequently, and the number of charge / discharge cycles is reduced, thereby extending the life of the storage battery.

  Embodiments of the uninterruptible power supply apparatus of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of an uninterruptible power supply according to Embodiment 1 of the present invention. The uninterruptible power supply apparatus shown in FIG. 1 includes a regular uninterruptible power supply unit 1, a standby uninterruptible power supply unit 3, an electric double layer capacitor 9 that can be backed up for a short time, and a storage battery 11 that can be backed up for a long time. The storage battery 11 may be a lead storage battery or a storage battery such as lithium ion or nickel metal hydride.

  The common uninterruptible power supply unit 1 is connected to an AC input terminal, converts an AC from an AC power source into a DC, and converts the DC converted by the AC-DC converter into an AC again (reverse conversion). A DC-AC converter, and an uninterruptible switching circuit interposed between the output of the DC-AC converter and a load. Further, the service uninterruptible power supply unit 1 includes a bypass circuit between the bypass AC input terminal and the uninterruptible switching circuit, and the AC power supplied to the bypass AC input terminal includes the bypass circuit and the uninterruptible switching circuit. To be supplied to the load.

  The normal uninterruptible power supply unit 1 converts the alternating current of the alternating current power input to the alternating current input terminal through the alternating current input terminal AC IN into direct current, converts this direct current into a desired alternating current, and through the alternating current output terminal AC OUT. Supply to load.

  The standby uninterruptible power supply unit 3 is connected between the AC input terminal AC IN and the bypass AC input terminal of the normal uninterruptible power supply unit 1. When the AC-DC converter and the DC-AC converter are inspected or failed, the AC-DC converter and the DC-AC converter are operated by a switching signal from the normal uninterruptible power supply unit 1 to supply desired AC power to the bypass circuit of the normal uninterruptible power supply unit 1.

  In addition, an electric double layer capacitor 9 is connected to the service uninterruptible power supply unit 1, and the service uninterruptible power supply unit 1 charges and discharges the electric double layer capacitor 9. A storage battery 11 is connected to the standby uninterruptible power supply unit 3, and the standby uninterruptible power supply unit 3 charges and discharges the storage battery 11.

  That is, the standby uninterruptible power supply unit 3 uses the AC power obtained by converting the DC power stored in the storage battery 11 based on the switching signal from the regular uninterruptible power supply unit 1 as the “first AC power” of the present invention. The power can be supplied to the load via the bypass circuit and the uninterruptible switching circuit of the power failure power supply unit 1. Further, the uninterruptible power supply unit 1 is an AC power obtained by converting input AC power from an AC power source into DC power and converting the DC power again as “second AC power” of the present invention, and an electric double layer capacitor 9. At least one of the AC power converted from the DC power stored in the first AC power and the first AC power can be supplied to the load.

  When the AC power supply has an instantaneous power failure or voltage drop, the service uninterruptible power supply unit 1 discharges the electric double layer capacitor 9 and converts the DC power from the electric double layer capacitor 9 into AC power. Supply to load. The normal uninterruptible power supply unit 1 sends the pre-discharge signal Sg1 to the standby uninterruptible power supply unit 3 as a switching signal when the voltage (discharge voltage) of the electric double layer capacitor 9 becomes equal to or less than the specified value before the discharge. Send it out.

  The normal uninterruptible power supply unit 1 charges the electric double layer capacitor 9 when the AC power supply is restored and when the voltage drop is recovered, and the switching signal when the charging of the electric double layer capacitor 9 is almost completed. As a result, a charge completion signal Sg2 is sent to the backup uninterruptible power supply 3.

  The standby uninterruptible power supply unit 3 discharges the storage battery 11 based on the pre-discharge signal Sg1 from the regular uninterruptible power supply unit 1 and converts the DC power from the storage battery 11 into AC power to convert the uninterruptible power supply unit 1 To the load via a bypass circuit (not shown).

  Next, the operation of the uninterruptible power supply according to the first embodiment configured as described above will be described in detail with reference to the flowchart shown in FIG.

  First, during normal times when the AC power supply is normal, the uninterruptible power supply unit 1 converts AC to DC, converts the DC power to AC power, and supplies stable AC power to the load (step S1). The standby uninterruptible power supply 3 is in a standby state.

  At the same time, each of the normal uninterruptible power supply unit 1 and the standby uninterruptible power supply unit 3 performs a charging operation, and the electric double layer capacitor 9 and the storage battery 11 are charged.

  Next, the normal uninterruptible power supply unit 1 determines whether the AC power supply has an instantaneous power failure or whether the instantaneous voltage has dropped (step S3). When the voltage drops, the electric double layer capacitor 9 is switched from charging to discharging (step S5), and stable electric power is continuously supplied from the electric double layer capacitor 9 to the load.

  Next, the utility uninterruptible power supply unit 1 determines that the voltage across the electric double layer capacitor 9 is increased due to reasons such as when the power failure time of the AC power source becomes longer rather than instantaneous or when the voltage drop time becomes longer than instantaneous. When the value becomes equal to or less than the specified value before the end of discharge (step S7), a pre-discharge end signal Sg1 is sent to the standby uninterruptible power supply 3 (step S9).

  The standby uninterruptible power supply unit 3 switches from charging to discharging based on the pre-discharge signal Sg1 from the regular uninterruptible power supply unit 1 (step S11), discharges the storage battery 11 (step S13), and uses the storage battery 11 for normal use. Electric power is supplied to the load via the bypass circuit of the uninterruptible power supply unit 1.

  When the standby uninterruptible power supply unit 3 is a constant commercial power supply system, the pre-discharge end signal Sg1 is input to the standby uninterruptible power supply unit 3 and the inverter operation is performed without instantaneous interruption (the operation of the DC-AC converter). ).

  Next, the uninterruptible power supply unit 1 charges the electric double layer capacitor 9 (step S17) when the AC power is restored and when the voltage drop is recovered (step S15). When the charging is almost completed, a charging completion signal Sg2 is sent to the standby uninterruptible power supply 3 (step S19).

  The backup uninterruptible power supply unit 3 completes the backup operation by the storage battery 11 based on the charging completion signal Sg2 from the regular uninterruptible power supply unit 1 (step S21). Thereafter, the backup uninterruptible power supply 3 performs the charging operation of the storage battery 11.

  In addition, when the AC-DC converter and DC-AC converter of the common uninterruptible power supply unit 1 break down, the standby uninterruptible power supply unit 3 is uninterrupted via the bypass circuit of the common uninterruptible power supply unit 1. Continue to supply power to the load.

  Thus, according to the uninterruptible power supply of Example 1, when the AC power supply has an instantaneous power failure and an instantaneous voltage drop, the electric double layer capacitor 9 connected to the regular uninterruptible power supply unit 1 is discharged to the AC When power is supplied and the power failure time of the AC power source becomes longer or when the voltage drop time becomes longer, AC power is supplied to the load by the discharge operation of the storage battery 11 connected to the backup uninterruptible power source 3. to continue. For this reason, even at the time of frequent instantaneous power failure and instantaneous voltage drop of the AC power supply, the storage battery 11 has fewer charge / discharge cycles without repeating charge / discharge frequently, and the life of the storage battery 11 is extended.

  Moreover, the short-time backup is borne by the normal uninterruptible power supply unit 1 using the electric double layer capacitor 9, and the long-time backup is borne by the standby uninterruptible power supply unit 3 using the storage battery 11, which is economically shared. is doing.

  In addition, even when the storage battery 11 has previously deteriorated due to insufficient charging of the storage battery or due to temperature abnormality, the electric double layer capacitor 9 can be backed up in the event of an instantaneous power failure or an instantaneous voltage drop of the AC power supply.

  In addition, when the standby uninterruptible power supply unit 3 is always in the commercial power supply system, the standby uninterruptible power supply unit 3 is moved ahead by the process of sending the pre-discharge end signal Sg1 of the electric double layer capacitor 9 to the standby uninterruptible power supply unit 3. It is possible to switch to inverter operation, and AC power can be supplied to the load from the backup uninterruptible power supply unit 3 without interruption.

  In addition, after the AC power supply is restored and the voltage drop is recovered, the electric double layer capacitor 9 is charged before the backup of the backup uninterruptible power supply unit 3 is completed and the charging operation of the storage battery 11 is started. The capacitor 9 can be charged quickly and prepared for a subsequent instantaneous power failure.

It is a figure which shows the structure of the uninterruptible power supply of Example 1 of this invention. It is a flowchart which shows operation | movement of the uninterruptible power supply of Example 1 of this invention. It is a figure which shows the structure of the conventional uninterruptible power supply.

Explanation of symbols

1 Uninterruptible power supply unit 3 Backup uninterruptible power supply unit 9 Electric double layer capacitor 11 Storage battery

Claims (2)

A storage battery,
A standby uninterruptible power supply unit connected to an AC power source and the storage battery, and outputs a first AC power based on a switching signal and charges and discharges the storage battery;
An electric double layer capacitor;
A normal uninterruptible power supply unit that is connected to the AC power supply, the output side of the backup uninterruptible power supply unit and the electric double layer capacitor, and supplies the second AC power to the load and charges and discharges the electric double layer capacitor. And
The common uninterruptible power supply unit discharges the electric double layer capacitor to supply the second AC power to the load when the AC power supply is instantaneously interrupted and when the voltage drops instantaneously, and the electric double layer When the voltage across the capacitor is equal to or less than the specified value before the end of discharge, the signal before the end of discharge is sent to the backup uninterruptible power supply as the switching signal,
The backup uninterruptible power supply unit discharges the storage battery based on the pre-discharge signal and supplies the first AC power to the regular uninterruptible power supply unit.   When the AC power supply is restored and the voltage drop is recovered, the regular uninterruptible power supply unit charges the electric double layer capacitor, and the charging of the electric double layer capacitor is almost completed. 2. The uninterruptible power supply according to claim 1, wherein a charge completion signal is sent as a switching signal to the standby uninterruptible power supply.

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