JP2006246616A - Uninterruptible power supply - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an uninterruptible power supply that supplies electric power without interruption to a load device having a redundant power supply system. <P>SOLUTION: The uninterruptible power supply 10 comprises a first power supply system having a main power supply system 14 and a bypass line 15, and a second power supply system having a main power supply system 24 and another bypass line 25. The first power supply system supplies electric power to a first power supply module 41 of a load device 40, while the second power supply system supplies electric power to a second power supply module 42 of the load device 40. Normally, electric power is supplied from a common DC-AC inverter 34 belonging to the main power supply system, and upon a failure of commercial power supply, back-up power supply is performed by a battery 33. If the DC-AC inverter 34 fails, electric power is supplied with bypass lines 15, 25. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an uninterruptible power supply, and more particularly to an uninterruptible power supply that supplies redundant power to a load device having a redundant input power supply system.

  The uninterruptible power supply is widely used to supply AC power to various load devices. An uninterruptible power supply system has multiple power supply systems, and in the event of a commercial power failure, for example, a DC power supply for a battery installed for backup purposes is converted into an AC power supply via an inverter and supplied to a load. ing.

  By the way, power load redundancy having a plurality of input power supply systems is performed in important load devices such as a server of a computer system and a disk array device. When supplying power to such a load device having a plurality of input power supply systems, generally, a plurality of uninterruptible power supply devices (UPS devices) are operated in parallel to supply power to the load device. For this reason, the battery and the inverter of the capacity | capacitance which can supply the power consumption of a load apparatus are used by the number of UPS apparatuses. In this case, for example, a cost close to twice is required for duplexing, and a cost close to triple is required for triplexing. Also, the size and weight of the UPS device will increase to a size and weight that is nearly double and triple.

  Patent Document 1 describes a UPS device that supplies AC power to a load device having a redundant power supply system. FIG. 2 shows the configuration of the UPS device described in Patent Document 1. The UPS device 50 includes an overcurrent detection unit 51, a first AC power supply system 52 that supplies AC power to a first input terminal of the changeover switch 55, and an overcurrent detection unit 53. A second AC power supply system 54 for supplying AC power to the second input terminal; an AC-DC converter 57 for supplying power from the first and second AC power supply systems 42 and 54 to charge the battery 56; And an inverter 58 that converts the DC power from the battery 56 to AC power and supplies AC power to the third input terminal of the changeover switch 55.

In the UPS device, when the first and second AC power supply systems 52 and 54 are normal, the changeover switch 55 supplies power to the load device 60 from the first and second AC power supply systems 52 and 54, respectively. When an abnormality occurs in one or both of the first and second AC power supply systems 52, 54, AC power is supplied to the inverter 58 load device using the battery 56. Further, the battery 56 and the inverter 58 are shared by the two power supply systems 52 and 54, so that cost, size, and weight can be reduced.
JP 2004-254470 A (FIG. 1)

  In the UPS device described in Patent Document 1, two commercial power supplies are always input as they are to the input power supply system of the redundant load device 60, and when an abnormality occurs in the commercial power supply or the like, the abnormality is detected. Based on this, the AC power supply is switched and controlled. In this case, for example, when two commercial power supplies are simultaneously cut off, the two input power supplies disappear simultaneously and the inverter 58 is started. However, since a time delay occurs in the rise of the inverter 58, there is a problem that necessary power is not supplied to the load device 60 during that time. Further, since there is only one AC / DC converter, there is a problem that backup cannot be performed in the case of maintenance or failure.

  The present invention is a UPS device particularly suitable for supplying power to a load device in which an input power supply system is made redundant, and can be reduced in cost, size and weight. Even if a power failure occurs, the power is supplied to the load without any interruption, so the object is to provide a UPS device with excellent backup capability.

To achieve the above object, an uninterruptible power supply of the present invention is an uninterruptible power supply that supplies power to a load device having a redundant input power supply system including first and second input power supply systems.
A common power supply portion having a battery and a DC / AC converter to which direct current power is supplied from the battery;
A first changeover switch having first and second input terminals and an output terminal connected to the first input power supply system; via a first power circuit breaker and a first AC / DC converter A first main power source for supplying a DC power source to the battery and supplying an AC power source from the battery to the first input terminal of the first changeover switch via the DC / AC converter. A first bypass power supply system that supplies AC power from the first power breaker to a second input terminal of the first power supply switch; and an output terminal of the first switch is connected to the first power switch. A first power supply system including a first switching control unit that switches to and connects to one of the input terminals of the first input terminal or the second input terminal;
A second changeover switch having first and second input terminals and an output terminal connected to the second input power supply system; via a second power circuit breaker and a second AC / DC converter A second main power source for supplying a DC power source to the battery and supplying an AC power source from the battery to the first input terminal of the second changeover switch via the DC / AC converter. A second bypass power supply system for supplying AC power from the second power circuit breaker to a second input terminal of the second power supply changeover switch, and an output terminal of the second changeover switch connected to the second power supply switch. And a second power supply system including a second switching control unit that switches to and connects to one of the first input terminal and the second input terminal.

  In the uninterruptible power supply of the present invention, since the battery is always charged and the common DC / AC converter (inverter) is operated in the power supply system, the structure of the power supply is simplified and the power supply When switching to a bypass line when a failure occurs in a device or a load device, it is possible to switch the power source without interruption. In addition, since the converter is provided in both the first and second power supply systems so that the battery can be charged from any of the converters, an uninterruptible power supply device having excellent backup capability when a failure occurs can be obtained.

  In the uninterruptible power supply according to a preferred aspect of the present invention, each of the first and second switching control units detects a power supply abnormality at least at an output terminal of the first and second power supply switching switches, respectively. It is preferable to switch the second power switch.

  It is also a preferred aspect of the present invention that each of the first and second AC / DC converters has a current capacity equal to or greater than the load current of the load device. In this case, it is possible to charge the battery while supplying power to the load device with only one AC-DC converter, and it is possible to perform backup with the battery in the event of a commercial power supply power failure that occurs thereafter.

  Hereinafter, the present invention will be described in more detail based on embodiments of the present invention with reference to the drawings. FIG. 1 shows the configuration of a UPS device according to an embodiment of the present invention. The UPS device 10 includes a first power supply system 31 and a second power supply system 32 to which power is supplied from a distribution board 43 to which commercial power is supplied via power supply lines 11 and 21, respectively. The power supply system 32 includes a battery 33 and a DC / AC inverter 34 which are common power supply parts common to both power supply systems 31 and 32.

  The load device 40 is, for example, a server of a computer system, a disk array, or the like, has two input power supply systems, and power supply modules 41 and 42 are respectively provided.

  The first power supply system 31 of the UPS device 10 is used for commercial purposes when the first main power supply system 14 constantly supplies power to the first power supply module 41 of the load device 40 and when the first main power supply system 14 is abnormal. A first bypass line 15 that supplies power by bypass, a first uninterruptible switching device 16, and a first switching control unit 17 are provided. The second power supply system 32 has a second main power supply system 24 that supplies power to the second power supply module 42, and a second power supply that bypasses and supplies commercial power when the second main power supply system 24 is abnormal. The bypass line 25, the second uninterruptible switching device 26, and the second switching control unit 27 are provided. In the second main power supply system 24, a battery 33, which is a power source common to the first and second main power supply systems, and a DC / AC inverter 34 to which direct current power is supplied from the battery 33 are disposed. The

  The main power supply system 14 of the first power supply system 31 is composed of an input breaker 12, a first AC / DC converter 13, a battery 33, and a DC / AC inverter 34 that constitute a first power breaker. The output of the DC / AC inverter 34 is connected to the first input terminal of the first uninterruptible switching device 16. The first bypass line 15 is configured as a wiring that connects the load-side terminal of the power breaker 12 and the second input terminal of the uninterruptible switching device 16. The main power supply system 24 of the second power supply system 32 includes an input breaker 22, a second AC / DC converter 23, a battery 33, and a DC / AC inverter 34 that constitute a second power breaker. The output of the DC / AC inverter 34 is connected to the first input terminal of the second uninterruptible switching device 26. The second bypass line 25 is configured as a wiring connecting the load side terminal of the power breaker 12 and the second input terminal of the second uninterruptible switching device 26.

  The UPS device 10 of the present embodiment is a redundant power supply device that supplies two systems of power to a load device 40 having an input power supply system that is redundant into two systems. When the load device has a power supply system multiplexed in three or more layers, one or more power supply systems corresponding to the first power supply system 31 are additionally provided. That is, one or more first power supply systems are added according to the degree of multiplexing. In this case, depending on the number of additional power supply systems, the same number or less batteries and DC / AC inverters may be added.

  The UPS device 10 according to the embodiment includes two power supply systems 31 and 32 corresponding to the power supply configuration of the load device 40 having a redundant configuration. For this reason, even if one power supply system becomes unable to supply power due to a trip of the power breaker or the like, a redundant configuration is adopted in which power can be supplied from the other normal power supply system. At the same time, in order to suppress an increase in cost, size, and weight of the UPS device 10, the inverter and the battery are not redundant, and constitute the UPS device.

  The UPS device 10 having the above configuration has the following functions. Normally, the main power supply systems 14 and 24 of the power supply systems 31 and 32 receive power from the commercial power supplied from the distribution board 43, and the AC / DC converters 13 and 23, the DC / AC inverter 34, and the Power is supplied to the power supply modules 41 and 42 of the load device 40 via the instantaneous interruption switching devices 18 and 28, respectively. A part of the DC power supplied from the AC / DC converters 13 and 23 is stored in the battery 33.

  The power circuit breakers 11 and 21 are normally supplied with commercial power, supply the commercial power to the first and second power supply systems 31 and 32 of the UPS device 10, and trip when an overcurrent occurs. The internal circuit of the device 10 and the internal circuit of the load device 40 are protected. The AC / DC converters 13 and 23 convert commercial power into direct current and supply the output to the battery 33 and the DC / AC inverter 34. The battery 33 is normally charged by the DC output of the AC / DC converters 13 and 23, and supplies a DC current to the DC / AC inverter 34 during a power failure of the commercial power supply. The inverter 34 converts the direct current fed from the AC / DC converters 13 and 23 into an alternating current and outputs the alternating current. Further, in the event of a power failure of the commercial power supply, the direct current from the battery 33 is converted into an alternating current and output.

  The uninterruptible switching devices 16 and 26 select and output an alternating current power source that is an output of the DC / AC inverter 34 supplied to the first input terminal in a normal state, and switch control units 17 and 27 in an abnormal state. In accordance with the control, the commercial power supplied to the second input terminal is selected and output, and power is supplied to the power modules 41 and 42 of the load device 40, respectively. The switching control units 17 and 27 constantly monitor the output lines 18 and 28 of the uninterruptible switching devices 16 and 26, and supply the power sources of the respective power supply systems 31 and 32 to the output of the DC / AC inverter 34 or the bypass line. Switch between 15 and 25 outputs. For example, when an overcurrent occurs in the output lines 18 and 28 of the uninterruptible switching devices 16 and 26, the switching is made to the bypass lines 15 and 25, and in other normal times, the output is switched to the inverter output.

  The operation corresponding to the occurrence of a failure in the UPS device of the above embodiment will be described in more detail. First, at a normal time, commercial power is supplied to the distribution board 43, and commercial power is supplied to both power systems 31, 32 of the UPS device 10 via the power lines 11, 21. The commercial power supply passes through the AC / DC converters 13 and 23, the inverter 34, the uninterruptible switching devices 16 and 28, and the output lines 18 and 28, and the first and second power supply modules 41 and 42 of the load device 40. Are supplied respectively.

  When the load device 40 is turned on, an overcurrent may temporarily flow through the output lines 18 and 28 of the uninterruptible switching devices 16 and 26 due to a large starting current of the load device 40. In this case, the switching control units 17 and 27 detect this overcurrent, control the uninterruptible switching devices 16 and 26, and switch the load current to the bypass lines 15 and 25. This protects the internal circuit of the UPS device 10 from a large overcurrent. When the overcurrent returns to the normal current, the switching control units 17 and 27 again control the uninterruptible switching devices 16 and 26 to switch to the output of the DC / AC inverter 34.

  When an overcurrent occurs in the output lines 18 and 28 of the UPS device 10, the switching control units 17 and 27 switch only the corresponding uninterruptible switching devices 16 and 26 to the outputs of the bypass lines 15 and 25. It is considered that the overcurrent caused by the starting current of the load device 40 occurs simultaneously in both the output lines 18 and 28. Therefore, in this case, it is considered that switching to the bypass lines 15 and 25 occurs in both the power supply systems 31 and 32. However, in the case of a short circuit failure of the power supply modules 41 and 42, it is considered that overcurrent occurs only in one of the output lines 18 and 28. In this case, only one power supply system is switched to the bypass line.

  When an overcurrent exceeding the current capacity of the power breakers 12 and 22 occurs, one of the power breakers 12 and 22 where the overcurrent has occurred is cut off, and the other power breaker continues to supply power. In this case, the battery 33 is charged by the AC / DC converters 14 and 24, and a backup operation that is switched to battery power feeding is possible even if the commercial power supply subsequently fails.

  When a failure occurs in the AC / DC converter 13 of the first power supply system 31, the failed AC / DC converter 13 is stopped and switched to the bypass line 15 to supply power to the first power supply module 41. To do. Also in this case, the battery 33 is charged from the other converter 23, and the backup operation can be performed by the power supply from the battery 33 even if the commercial power supply subsequently fails.

  When the DC / AC inverter 34 fails or when both AC / DC converters 13 and 23 fail, power is supplied via the bypass lines 15 and 25 of both power systems 31 and 32. In this case, the commercial power from the distribution board 43 is used as it is as the AC output of the UPS device 10 to continue power supply, and the power is supplied to the load device 40. In this case, when a power failure occurs thereafter, the backup operation using the battery 33 cannot be performed.

  As described above, the UPS device of the above embodiment has the following effects. The first effect is to reduce the cost, size, and weight of the redundant UPS device because the battery and the inverter are common to both power supply systems. The second effect is that the AC / DC converter is made redundant, so that even if one AC output switches to the bypass line or one power breaker trips, the remaining normal AC / DC Since the power supply system including the converter can continue to supply AC output and the battery is charged, the battery can be backed up even if a power failure occurs thereafter. The third effect is that the inverter power is always supplied, so that backup without interruption is possible when a failure occurs in the power supply device or the load device.

  Although the present invention has been described based on the preferred embodiment, the UPS device of the present invention is not limited to the configuration of the above embodiment, and various modifications and changes can be made from the configuration of the above embodiment. Those applied are also included in the scope of the present invention. In addition, each configuration described as a preferred aspect of the present invention or each configuration described in the embodiment is preferably used together with the essential configuration of the present invention, but about a configuration that exhibits a beneficial effect even when used alone. However, it is not always necessary to use all the configurations described as the essential configurations of the present invention.

  The UPS device of the present invention can be used as an uninterruptible power supply for a load device in which an input power supply system is made redundant.

It is a block diagram of the uninterruptible power supply concerning one embodiment of the present invention. It is a block diagram of the conventional uninterruptible power supply.

Explanation of symbols

10: UPS device (uninterruptible power supply)
11, 21: Power line 12, 22: Input circuit breaker (input breaker)
13, 23: AC / DC converter 14, 24: Main power supply system 15, 25: Bypass line 16, 26: Uninterruptible switching device 17, 27: Control unit 18, 28: Output line 33: Battery 34: DC / AC Inverter 40: load device 41, 42: power supply module 43: distribution board 50: UPS device 51, 53: overcurrent detection unit 52: first power supply system 54: second power supply system 55: switching unit 56: battery 57 : AC / DC converter 58: Inverter 60: Load device

Claims (3)

In an uninterruptible power supply for supplying power to a load device having a redundant input power supply system including a first and a second input power supply system,
A common power supply portion having a battery and a DC / AC converter to which direct current power is supplied from the battery;
A first changeover switch having first and second input terminals and an output terminal connected to the first input power supply system; via a first power circuit breaker and a first AC / DC converter A first main power source for supplying a DC power source to the battery and supplying an AC power source from the battery to the first input terminal of the first changeover switch via the DC / AC converter. A first bypass power supply system that supplies AC power from the first power breaker to a second input terminal of the first power supply switch; and an output terminal of the first switch is connected to the first power switch. A first power supply system including a first switching control unit that switches to and connects to one of the input terminals of the first input terminal or the second input terminal;
A second changeover switch having first and second input terminals and an output terminal connected to the second input power supply system; via a second power circuit breaker and a second AC / DC converter A second main power source for supplying a DC power source to the battery and supplying an AC power source from the battery to the first input terminal of the second changeover switch via the DC / AC converter. A second bypass power supply system for supplying AC power from the second power circuit breaker to a second input terminal of the second power supply switch, and an output terminal of the second switch switch for the second A second power supply system including a second switching control unit that switches to and connects to one of the input terminals of the first input terminal or the second input terminal;
An uninterruptible power supply comprising:   The first and second switching control sections detect a power supply abnormality at output terminals of the first and second power supply switching switches, respectively, and switch the first and second power supply switching switches. Uninterruptible power supply described in 1.   The uninterruptible power supply according to claim 1 or 2, wherein each of the first and second AC / DC converters has a current capacity equal to or greater than a load current of the load device.

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