JP2022143925A - Non-instantaneous interruption power supply switching device - Google Patents

Abstract

To provide a non-instantaneous interruption power supply switching device capable of effectively preventing an output of power when a phase of power supply of a switching source and a phase of voltage on an output side of the non-instantaneous interruption power supply switching device are different.SOLUTION: A non-instantaneous interruption power supply switching device 1 used for switching of a power supply device for supplying power to a load, comprises: a switching unit 13 that switches between a state where power is supplied to the load from a first power supply device and a state where power is supplied to the load from a second power supply device; a short-circuit prevention unit 14 that is placed between the power supply side and the load side, and reversibly switches between a conduction state and a disconnection state; a phase abnormality detection unit 20 that detects a phase difference between a voltage on the power supply side and a voltage on the load side; a wiring disconnector 31 that is placed on the power supply side between the phase abnormality detection unit and the short-circuit prevention unit, and interrupts a detection current when a value of a detection current flowing in the phase abnormality detection unit has become a predetermined threshold value or greater; and a detection unit that detects that the wiring disconnector 31 has interrupted the detection current.SELECTED DRAWING: Figure 1

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an uninterruptible power supply switching device that is suitable for use when switching a power supply such as an uninterruptible power supply.

2. Description of the Related Art An uninterruptible power supply (UPS) is known that supplies power from a built-in battery and continues power supply to a load in the event of a power failure or the like. Henceforth, an uninterruptible power supply (UPS) is also described as a "power supply device." Also known is an uninterrupted power supply switching device that can be replaced with a new power supply without stopping the power supply to the load when replacing the power supply.

When replacing a power supply device using a hitless power supply switching device, the phase of the voltage of the power supply device before replacement and the phase of the voltage of the power supply device after replacement need to match. For this reason, there is known an uninterrupted power supply switching apparatus equipped with a synchronization control circuit that controls the phase of the voltage of the power supply to enable switching even if the power supply is not synchronized (for example, See Patent Document 1.).

In addition, a sensor for comparing the voltage phase between the wiring lines is installed on the bus in the switch of the circuit, and when the voltage between the lines on both sides of the switch is out of phase, the switch is automatically prohibited from turning on. A multi-circuit switch is also known (see, for example, Patent Document 2).

Japanese Patent No. 3664902 JP-A-6-296331

In conventional uninterruptible power switching devices, for example, due to incorrect wiring, power is supplied from the uninterrupted power switching device in a state where the phase of the voltage of the switching source power supply and the phase of the voltage on the output side of the uninterrupted power switching device are different. is output, there is a problem that a short-circuit accident may occur.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. The present invention relates to an uninterrupted power supply switching device capable of effectively preventing power from being output from the switching device.

In order to achieve the above object, the present invention provides the following means.
An uninterruptible power switching apparatus of the present invention is an uninterruptible power switching apparatus used for switching a power supply apparatus that supplies power to a load, comprising: a first connection section to which a first power supply apparatus is connected; a second connection portion to which a second power supply device different from the first power supply device is connected; a third connection portion to which the load is connected; a state in which power is supplied from the first power supply device to the load; 2 a switching unit for switching between a state in which power is supplied from the power supply device to the load, a power source side on the side of the first connection portion and the second connection portion, and a load side on the side of the third connection portion. to reversibly switch between an energized state in which current flows between the power supply side and the load side and an interrupted state in which the current flow between the power supply side and the load side is interrupted. a switching short-circuit prevention unit; and a phase abnormality detection unit that detects a phase difference between a power-supply-side voltage in the short-circuit prevention unit and a load-side voltage in the short-circuit prevention unit. a phase abnormality detector and a short-circuit prevention unit disposed between the power supply side and interrupting the detected current when the value of the detected current flowing through the phase abnormality detector exceeds a predetermined threshold value; A protection unit and a detection unit that detects that the protection unit has interrupted the detection current are provided.

According to the uninterrupted power supply switching device of the present invention, the phase abnormality detection section is provided to detect the phase difference between the power supply side voltage and the load side voltage. The phase abnormality detection unit detects that the phases of the power supply voltage and the load voltage are different when the phase difference between the power supply voltage and the load voltage exceeds a predetermined range. Therefore, it is possible to determine that there is an erroneous connection in the wiring to the uninterrupted power supply switching device, and to take predetermined measures such as prohibiting the closing of the short-circuit prevention unit.

The uninterruptible power switching device also includes a protection unit that cuts off the current when a current greater than or equal to a predetermined threshold flows through the phase abnormality detection unit, and a detection unit that detects a state in which the protection unit cuts off the current. It has The protection unit operates when the value of the detected current flowing through the phase abnormality detection unit exceeds a predetermined threshold value, cuts off the current, and prevents excessive current from flowing through the phase abnormality detection unit. Also, the detection unit detects that the protection unit has cut off the current. In other words, the detection unit detects that the phase abnormality detection unit does not operate properly due to the operation of the protection unit. Therefore, it is possible to prevent the hitless power supply switching device from being used in a state in which the phase abnormality detection unit does not operate properly.

In the above invention, it is preferable that the protection section reversibly cut off the current.
By doing so, after removing the cause of the excessive current flowing through the phase error detection section, the protection section can be restored from the cut-off state, and the phase error detection section can be easily returned to an operable state. can be done.

In the above invention, when the phase abnormality detection section detects that the phase difference is equal to or greater than a predetermined magnitude, the short-circuit prevention section enters a state in which switching from the cut-off state to the energized state is restricted. It is preferable to be

By doing so, when the phase error detection section detects a phase difference equal to or greater than a predetermined magnitude, the short-circuit prevention section enters a state in which switching from the cut-off state to the energized state is restricted. That is, when the power supply side voltage and the load side voltage are out of phase due to miswiring or the like, the switching of the short-circuit prevention unit to the energized state is regulated, and the occurrence of a short-circuit accident can be prevented.

In the above invention, between the first connecting portion and the switching portion, between the second connecting portion and the switching portion, and between the third connecting portion and the short-circuit preventing portion. is provided with a reverse phase detection unit for detecting a reverse phase, and when at least one of the reverse phase detection units detects the reverse phase, the short circuit prevention unit is restricted from switching from the cut-off state to the energized state. It is preferable to be in a state where

By doing so, if any of the voltage input from the first connection portion, the voltage input from the second connection portion, and the voltage on the load side of the short circuit prevention portion is in reverse phase, the A reversed phase detector detects the reversed phase. Then, when any of the reverse phase detectors detects the reverse phase, the short circuit prevention unit enters a state in which switching to the energized state is restricted. This makes it possible to prevent the short-circuit prevention unit from switching to the energized state when the wiring to the uninterrupted power supply switching device is incorrect.

According to the hitless power switching device of the present invention, power is output from the hitless power switching device when the phase of the switching source power source and the phase of the voltage on the output side of the hitless power switching device are different. There is an effect that it is possible to effectively prevent it from being done.

FIG. 2 is a block diagram illustrating an overview of replacement work for an uninterruptible power supply using the uninterruptible power supply switching device according to the first embodiment of the present invention; 1 is a block diagram illustrating the configuration of an uninterrupted power switching device according to a first embodiment of the present invention; FIG. FIG. 3(a) is a block diagram for explaining the operation of the phase abnormality detection unit of the hitless power supply switching device of the first embodiment when the phases are the same. FIG. 3B is a block diagram for explaining the operation of the phase abnormality detection unit of the uninterrupted power supply switching device of the first embodiment when a phase abnormality occurs. 1 is a block diagram illustrating part of the configuration of an uninterrupted power switching device according to a first embodiment of the present invention; FIG. FIG. 7 is a block diagram illustrating the configuration of a hitless power supply switching device according to a second embodiment of the present invention;

[First Embodiment]
A hitless power supply switching device 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG.

The uninterruptible power supply switching device 1 of the present embodiment can replace an uninterruptible power supply that supplies power to a load such as an ICT device with a new uninterruptible power supply without stopping power supply to the load. It is a power supply switching device used. In this embodiment, the uninterruptible power supply switching device 1 is used for the work of replacing the existing uninterruptible power supply 4A with the newly installed uninterruptible power supply 4B without momentarily interrupting the power supply to the ICT devices 6a to 6c. The following description will be given by taking the case of use as an example (see FIG. 1). In the following description, the work of replacing the existing uninterruptible power supply 4A and the new uninterruptible power supply 4B is also referred to as "replacement work". Also, the ICT devices 6a to 6c are collectively referred to as "ICT device 6". The ICT device 6 of this embodiment is an example of the load.

In this embodiment, the uninterruptible power supply 4A and the uninterruptible power supply 4B are applied to an example that is a power supply that outputs an AC voltage of 200V. note that. The uninterruptible power supply 4A and the uninterruptible power supply 4B may be power supplies that output an AC voltage of 400V. Alternatively, it may be a power supply device that outputs a voltage of another magnitude.

1. Description of Configuration The uninterrupted power supply switching device 1 includes non-trip switches 11A and 11B, circuit breakers 12A and 12B for wiring, switching section 13, circuit breaker for wiring 14, input sections 15A and 15B, output section 16, and an external power supply terminal. 17a and 17b, a phase abnormality detector 20, and a circuit breaker 31 (see FIG. 2). The hitless power supply switching device 1 further includes an input power phase detection unit (not shown) for detecting a phase difference between the power input from the input unit 15A and the input unit 15B.

15 A of input parts are parts into which the electric power output from 4 A of existing uninterruptible power supplies is input. The input unit 15A is connected via a cable 52 to a branch board 41A provided on the output side of the uninterruptible power supply 4A during replacement work. The input unit 15B is a portion to which electric power is input from the newly installed uninterruptible power supply 4B. The input unit 15B is connected via a cable 54 to a branch board 41B provided at the output unit of the uninterruptible power supply 4B during replacement work. 15 A of input parts in this embodiment are an example of a 1st connection part. The input section 15B in this embodiment is an example of a second connection section.

The output section 16 is a section that outputs either power input from the input section 15A or the input section 15B. The output unit 16 is connected to the distribution board 5 via a cable 53 during replacement work. The output section 16 in this embodiment is an example of a third connection section. Hereinafter, the side provided with the input units 15A and 15B of the uninterrupted power switching device 1 is also referred to as the "power supply side", and the side provided with the output unit 16 is also referred to as the "load side".

The external power supply terminals 17a and 17b are portions to which a power cable (not shown) is connected, and are portions to which electric power necessary for operating the uninterrupted power switching device 1 is input. The non-trip switch 11A is a known switch provided on the side of the input section 15A. The non-trip switch 11B is a known switch provided on the side of the input section 15B.

The wiring circuit breaker 14 is a known wiring circuit breaker (MCCB) provided on the output section 16 side. When a predetermined operation is performed, the circuit breaker 14 has two states: an energized state in which current flows between the power supply side and the load side, and an interrupted state in which the current between the power supply side and the load side is interrupted. switches reversibly. When the circuit breaker for wiring 14 is energized, the power input from the input section 15A or the input section 15B is output from the output section 16 . When the circuit breaker 14 for wiring is in an interruption state, the electric power input from the input section 15A or the input section 15B is cut off by the circuit breaker 14 for wiring.

The circuit breaker 14 for wiring includes a signal input section (not shown) to which an abnormal signal is input from the phase abnormality detection section 20, which will be described later in detail. The circuit breaker 14 for wiring is configured to be in a cut-off state when an abnormality signal is input, and to restrict switching from the cut-off state to the energized state. Hereinafter, the state of the circuit breaker 14 in which an abnormal signal is input and switching from the cut-off state to the energized state is restricted is also referred to as a "tripped state". In addition, the circuit breaker 14 for wiring in this embodiment is an example of a short-circuit prevention part.

The switching unit 13 is a known wiring switching device provided on the power supply side of the circuit breaker 14 for wiring. The switching unit 13 switches between a state in which the input unit 15A and the circuit breaker 14 are electrically connected and a state in which the input unit 15B and the circuit breaker 14 are electrically connected according to the operation by the operator. In other words, the source of power output from the output unit 16 is switched between the uninterruptible power supply 4A and the uninterruptible power supply 4B.

The wiring circuit breaker 12A is a known wiring circuit breaker (MCCB) provided between the non-trip switch 11A and the switching unit 13 . The circuit breaker 12B for wiring is a known circuit breaker for wiring (MCCB) provided between the non-trip switch 11B and the switching unit 13 .

The phase abnormality detection unit 20 is a part that detects a phase shift between the voltage on the power supply side and the voltage on the load side of the circuit breaker 14 for wiring. The phase anomaly detector 20 is configured to output an anomaly signal notifying that the detected phase shift is greater than or equal to a predetermined range.

The phase abnormality detection section 20 includes a transformer 21, a transformer 22, and a voltage detection section 23 (see FIGS. 3A and 3B). The transformers 21 and 22 are known transformers that convert voltages input to their respective primary sides into voltages that can be operated by a voltage detection unit 23, which will be described later in detail, and output the voltages.

The primary side of the transformer 21 is connected to the power supply side of the circuit breaker 14 for wiring. In this embodiment, the voltage input sections 24a and 26a on the primary side of the transformer 21 are connected to the _U01 phase and _W01 phase on the power supply side of the wiring breaker 14 via wiring cables 28a and 29a, respectively. The following description will be made using the case as an example (see FIGS. 2 and 3(a) and (b)).

The primary side of the transformer 22 is connected to the load side of the circuit breaker 14 for wiring. In this embodiment, the voltage input sections 24b and 26b on the primary side of the transformer 22 are connected to the _U0 phase and _W0 phase on the load side of the circuit breaker 14 via wiring cables 28b and 29b. An example will be described below (see FIG. 2 and FIGS. 3A and 3B).

The voltage detection unit 23 is a part that detects a voltage difference between both ends and outputs an abnormal signal when the voltage difference exceeds a predetermined threshold value. In the present embodiment, the voltage detection unit 23 uses, as an example, a voltage sensitive relay that operates when the voltage difference between both ends becomes greater than a predetermined threshold value. It should be noted that the voltage detection unit 23 may be another known electrical component or the like that operates when a predetermined voltage difference occurs and outputs a signal that notifies the occurrence of the voltage difference.

One end of the voltage detection section 23 is connected to the voltage output section 44 a on the secondary side of the transformer 21 . The other end of the voltage detection section 23 is connected to the voltage output section 44 b on the secondary side of the transformer 22 . The voltage output section 46a on the secondary side of the transformer 21 and the voltage output section 46b on the secondary side of the transformer 22 are connected to each other so as to have the same potential (FIGS. 3A and 3B). reference.). The voltage output section 44a and the voltage output section 44b, and the voltage output section 46a and the voltage output section 46b are sections to which corresponding voltage phases are output.

When the transformer 21, the transformer 22, and the voltage detection unit 23 are connected in this way, the voltage detection unit 23 receives a The resulting voltage is applied. Specifically, when the circuit breaker for wiring 14 is in the cut-off state and the phase of the power supply on the power supply side of the circuit breaker for wiring 14 and the phase of the power supply on the load side are the same, the transformer 21 The voltage on the next side and the voltage on the secondary side of the transformer 22 have the same phase. At this time, no voltage is applied to the voltage detection section 23 because no potential difference occurs between the voltage output section 44a and the voltage output section 44b (see FIG. 3A). That is, the voltage detection unit 23 does not detect the voltage caused by the voltage phase shift.

On the other hand, if the phase of the voltage on the power supply side of the circuit breaker for wiring 14 is different from the phase of the voltage on the load side of the circuit breaker for wiring 14 when the circuit breaker for wiring 14 is in the interrupting state, the potential difference between the voltage output section 44a and the voltage output section 44b is occurs. That is, a phase difference voltage is applied to the voltage detection unit 23 (see FIG. 3B), and the voltage detection unit 23 detects that the phases of the voltages on the power supply side and the load side of the circuit breaker 14 are different. . That is, the phase abnormality detection section 20 detects a phase shift between the voltages on the power supply side and the load side of the circuit breaker 14 for wiring, based on the voltage detected by the voltage detection section 23 . When the magnitude of the voltage generated by this phase difference becomes equal to or greater than a predetermined range, the phase abnormality detection section 20 outputs an abnormality signal to notify that fact.

A circuit breaker 31 for wiring is provided on one side of the wiring connecting between the phase abnormality detection unit 20 and the power supply side of the circuit breaker 14 for wiring. This embodiment is applied to an example in which the wiring breaker 31 is provided on the wiring cable 28a that connects the voltage input section 24a on the primary side of the transformer 21 and the _U01 phase on the power supply side of the wiring breaker 14. The following description will be given.

The circuit breaker 31 for wiring is a known circuit breaker for wiring (MCCB) that is actuated to cut off the flow of current when the current flowing through the phase abnormality detection unit 20 exceeds a predetermined value. Hereinafter, the current flowing through the phase abnormality detection section 20 is also referred to as "detection current". That is, when the detected current exceeds a predetermined threshold value, the wiring circuit breaker 31 changes from an energized state in which current flows to a cut-off state in which the current flow is cut off, and an excessive current flows to the phase abnormality detection unit 20. prevent. The circuit breaker 31 for wiring in this embodiment is an example of the protection section.

An error lamp 32 is connected to the wiring circuit breaker 31 so as to be turned on when the wiring circuit breaker 31 is in a state of interrupting current flow (see FIG. 4). The fault lamp 32 has a control circuit (not shown), and is configured to turn off when the circuit breaker 31 for wiring is in an energized state and to light up when the circuit breaker 31 for wiring is in an interrupted state. . The abnormality lamp 32 in this embodiment is an example of the detection section.

2. Explanation of Action Next, the action of the uninterrupted power switching device 1 of the present embodiment will be explained according to its usage. First, mainly with reference to FIG. 1, an overview of the work of replacing the uninterruptible power supply 4A and the uninterruptible power supply 4B using the uninterruptible power supply switching device 1 will be described.

In the state before work, the existing uninterruptible power supply 4A is connected to the distribution board 5 via the branch board 41A and the cable 51, and supplies power to the ICT device 6. The uninterruptible power supply 4A is connected to a 200V commercial power supply 2A via an input panel 3A. A new uninterruptible power supply 4B replacing the uninterruptible power supply 4A is connected to a 200V commercial power supply 2B via an input panel 3B. The commercial power source 2A and the commercial power source 2B may be the same commercial power source.

Before starting the replacement work, the operation of the hitless power supply switching device 1 is checked. Specifically, using a dedicated test kit (not shown) or the like, a test voltage is input to a predetermined location to confirm that the hitless power supply switching device 1 operates correctly.

After confirming the operation of the uninterruptible power supply switching device 1, a cable 52 is used to connect the branch board 41A of the uninterruptible power supply 4A and the input unit 15A. Subsequently, the cable 54 connects between the branch board 41B of the uninterruptible power supply 4B and the input section 15B. At this time, the non-trip switch 11A and the non-trip switch 11B are kept open.

Next, a cable 55 for connecting the uninterruptible power supply 4B and the distribution board 5 is laid. Also, a cable 53 for connecting the uninterrupted power switching device 1 and the distribution board 5 is laid. At this time, both ends of the cables 53 and 55 are not connected to any part.

A power supply cable (not shown) is connected to the external power supply terminals 17a and 17b to supply power to the uninterrupted power supply switching device 1 . Power is preferably supplied to the uninterruptible power supply switching device 1 from a power supply device different from the uninterruptible power supply devices 4A and 4B.

By closing the non-trip switches 11A and 11B and energizing the circuit breaker 14, it is confirmed whether the phases of the power sources of the uninterruptible power supply 4A and the uninterruptible power supply 4B are synchronized. This confirmation is performed by a known input power source phase detector (not shown) of the uninterrupted power switching device 1 . Subsequently, the switching unit 13 is operated to set the power from the uninterruptible power supply 4B to be output from the output unit 16, and it is confirmed that the output voltage from the uninterruptible power supply switching device 1 is normal. do. Also, the switching unit 13 is operated to set the power from the uninterruptible power supply 4A to be output from the output unit 16, and it is confirmed that the output from the uninterruptible power supply switching device 1 is normal. This output is confirmed by connecting a known measuring instrument to the analyzer measuring terminal.

After confirming that there is no abnormality in the output from the uninterruptible power supply switching device 1 , the wiring circuit breaker 14 is set to the cut-off state, and the output section 16 is connected to the distribution board 5 using the cable 53 . At this time, the switching unit 13 is set to a state in which the power input from the uninterruptible power supply 4A is output from the output unit 16 .

Power is supplied from the uninterruptible power supply 4A to the distribution board 5 via a cable 51 . Therefore, when wiring is performed as described above, the voltage of the uninterruptible power supply 4A appears on the load side of the circuit breaker 14 for wiring. Further, the voltage of the uninterruptible power supply 4A input from the input section 15A appears on the power supply side of the circuit breaker 14 for wiring.

In this state, for example, if the cable 53 is wired with the wrong phase or the cable 52 is wired with the wrong phase, the phase of the power supply on the load side and the power supply side of the circuit breaker for wiring 14 will be different. becomes displaced. If the wiring circuit breaker 14 is energized in such a state, a short circuit accident will occur. On the other hand, in the uninterruptible power supply switching device 1 of the present embodiment, the phase abnormality detection section 20 detects this state of phase deviation, and the wiring circuit breaker 14 is restricted from being energized.

Specifically, when the load side and the power supply side of the circuit breaker 14 are out of phase with each other, the phase abnormality detection unit 20 detects the out-of-phase state, that is, phase and output an abnormal signal to the circuit breaker 14 for wiring. The circuit breaker 14 to which the abnormal signal is input is restricted from being energized. Specifically, when the abnormal signal is input, the circuit breaker 14 for wiring is in a tripped state, and the energized state is regulated. Therefore, even if the user operates the circuit breaker 14, the wiring circuit breaker 14 will not be energized, thereby preventing the occurrence of a short-circuit accident.

When the load side and the power supply side of the circuit breaker 14 are out of phase and an excessive current flows to the phase abnormality detection section 20, the circuit breaker 31 for wiring operates to cut off. That is, the circuit breaker 31 cuts off the detection current flowing through the phase abnormality detection unit 20 . Further, when the circuit breaker 31 for wiring is in the cutoff state, the abnormality lamp 32 is lit. That is, when the abnormality lamp 32 is lit, the operator can know that the wiring circuit breaker 31 is in an interrupted state and the phase abnormality detection section 20 is in a non-operating state.

When an abnormal signal is output from the phase abnormality detection unit 20 and the circuit breaker 14 for wiring is in a trip state, the operator checks the wiring state, reconnects the wiring correctly, and continues the work. After eliminating the cause of the operation of the circuit breaker 31 for wiring, the operator restores the circuit breaker 31 for wiring to the energized state. At this time, the operator confirms that the abnormality lamp 32 is extinguished and confirms that the phase abnormality detection section 20 is in a state of being able to operate properly.

After the cable 53 is connected, the wiring circuit breaker 14 is turned on. At this time, the distribution board 5 receives power from the uninterruptible power supply 4A via the cable 51, as well as power from the uninterruptible power supply 4A via the cable 52, the uninterruptible power switching device 1, and the cable 53. Power is supplied. After the wiring circuit breaker 14 is turned on, it is confirmed using a known ammeter or the like that current is correctly flowing through the cables 52 and 53 . After confirming that the current is correctly flowing through the cables 52 and 53, the connection between the uninterruptible power supply 4A and the distribution board 5 is cut off, and the cable 51 is removed.

After the cable 51 is removed, the switching unit 13 is switched so that the power from the uninterruptible power supply 4B is output to the output unit 16 . When switching unit 13 is switched, power from uninterruptible power supply 4B is supplied to distribution board 5 via cable 54 , uninterruptible power supply switching apparatus 1 and cable 53 . Then, using a known ammeter or the like, it is confirmed that the current is correctly flowing through the cables 53 and 54 , and the branch board 41 B is connected to the distribution board 5 using the cable 55 . Then, using a known ammeter or the like, it is confirmed that the current is correctly flowing through the cable 55 .

After confirming that the current is correctly flowing through the cable 55, the circuit breaker 14 for wiring is brought into a cut-off state, and an operation prohibition display is displayed. Subsequently, the circuit breakers 12A and 12B for wiring are put into the cut-off state. Using a known ammeter or the like, it is confirmed that no current is flowing through the cables 52, 53 and 54, respectively, and power supply to the uninterruptible power switching device 1 is stopped. Then, the cables 52, 53, 54 are removed to complete the work.

According to the uninterruptible power supply switching device 1 described above, the phase of the power supply side voltage and the load side voltage of the wiring circuit breaker 14 is different due to, for example, misconnection of the cable, and the phase abnormality detection unit 20 When the current flows, the circuit breaker 31 for wiring is in the breaking state. Therefore, the uninterrupted power supply switching device 1 can prevent an excessive current from flowing to the phase abnormality detection section 20, and can prevent an unintended problem such as a failure of the phase abnormality detection section 20 from occurring. Become.

On the other hand, when the hard-wired circuit breaker 31 is in the interrupting state, the phase abnormality detection unit 20 does not operate and the phase difference between the power supply side voltage and the load side voltage of the hard-wired circuit breaker 14 is not detected. If an operator turns on the circuit breaker 14 in such a state, the circuit breaker 14 may become energized with the voltage on the power supply side and the voltage on the load side out of phase.

However, in the uninterruptible power supply switching device 1 of the present embodiment, the error lamp 32 is lit when the circuit breaker 31 for wiring is in the interrupted state. It can be easily known that the voltage phase difference is not detected. In other words, it is possible to prevent the operator from turning on the circuit breaker 14 while the phase abnormality detector 20 is not operating.

Further, as the wiring circuit breaker 31, a known wiring circuit breaker (MCCB) is used. Therefore, the circuit breaker 31 for wiring cuts off the current reversibly when an excessive detected current flows. Therefore, the operator can switch from the cut-off state to the energized state with a simple operation. That is, after eliminating the cause of the interruption state, the circuit breaker 31 for wiring can be easily restored to the energized state in which the phase abnormality detection section 20 can operate.

Further, the phase anomaly detector 20 is configured to output an anomaly signal when the detected phase shift exceeds a predetermined range. When an abnormal signal is output from the phase abnormality detection unit 20, the circuit breaker 14 for wiring enters a trip state in which switching from the cut-off state to the energized state is restricted. Therefore, the hitless power supply switching device 1 can effectively prevent the wiring circuit breaker 14 from being energized when the phases of the power supply side voltage and the load side voltage are different. That is, it becomes possible to effectively prevent the occurrence of a short-circuit accident.

[Second embodiment]
Next, a second embodiment of the invention will be described mainly with reference to FIG.
The basic configuration of an uninterrupted power switching device 1A of this embodiment is the same as that of the first embodiment, but is different from the first embodiment in that it includes a reverse phase detector that detects a reverse phase. is doing. Therefore, in this embodiment, the same symbols are assigned to the same configurations as in the first embodiment, and the description thereof is omitted, and the points of difference are mainly described.

The uninterrupted power switching device 1A of this embodiment includes reverse phase detectors 33A, 33B, and . The reverse-phase detectors 33A, 33B, and 34 detect the phase of the voltage at the connected predetermined points, and operate when it is reverse-phase to output a reverse-phase notification signal to notify that fact. be.

In the present embodiment, the negative phase detectors 33A, 33B, and 34 are applied to an example in which a known electrical component called a positive phase detection relay or a negative phase relay is used for the following description. The reverse phase detectors 33A, 33B, and 34 are operated when the voltage at a predetermined connected point is reverse phase, and other known electric parts or the like are used as long as they output a reverse phase notification signal. may be used.

33 A of reverse phase detection parts detect the phase of the voltage input from the input part 15A. In the present embodiment, the negative phase detector 33A is applied to each phase between the non-trip switch 11A and the hard-wired circuit breaker 12A for the following description. The reverse phase detection unit 33A may be connected to a location different from the above as long as it is closer to the power source than the switching unit 13 and can detect the phase of the voltage input from the input unit 15A.

The reverse phase detection section 33B detects the phase of the voltage input from the input section 15B. In the present embodiment, the negative phase detector 33B is applied to each phase between the non-trip switch 11B and the circuit breaker 12B for the following description. The reverse phase detector 33B may be connected to a location different from the above as long as it is closer to the power source than the switching unit 13 and can detect the phase of the voltage input from the input unit 15B.

The reverse phase detection section 34 is a section that detects the phase of the voltage in the output section 16 . In the present embodiment, the reverse phase detection section 34 is applied to each phase of the output section 16 for the following description. The reverse phase detection unit 34 may be connected to a location different from the above as long as it can detect each phase of the voltage of the output unit 16 .

The wiring breaker 14A has a signal input section (not shown) to which the abnormal signal from the phase abnormality detection section 20 and the negative phase notification signals from the negative phase detection sections 33A, 33B, and 34 are input. The circuit breaker 14A for wiring is configured to be in a trip state when the reverse phase notification signal is input.

For example, if the cable 52 is erroneously connected and a reverse-phase voltage is input to the input section 15A, the reverse-phase detection section 33A detects this state and outputs a reverse-phase notification signal. Further, for example, if the cable 54 is erroneously connected and a reversed-phase voltage is input to the input section 15B, the reversed-phase detection section 33B detects this state and outputs a reversed-phase notification signal. If the cable 53 is erroneously connected and a reversed-phase voltage appears at the output section 16, the reversed-phase detection section 34 detects this state and outputs a reversed-phase notification signal. Then, when a negative phase notification signal is output from any one of the negative phase detectors 33A, 33B, and 34, the circuit breaker 14A for wiring enters a trip state, and switching from the cutoff state to the energized state is regulated.

According to the uninterruptible power switching device 1A of the present embodiment, when the voltage input from the input section 15A, the voltage input from the input section 15B, or the voltage appearing at the output section 16 is in reverse phase, The wiring circuit breaker 14A is restricted from being in a tripped state and in an energized state. Therefore, it is possible to prevent the wiring circuit breaker 14A from being turned on while the phase is reversed due to incorrect cable connection. In other words, it is possible to effectively prevent the wiring circuit breaker 14A from being energized while the cable is erroneously connected. In other words, in the uninterruptible power switching device 1A, the phases of the power supply side voltage and the load side voltage of the circuit breaker 14A are different, and the voltages of the input sections 15A and 15B and the voltage of the output section 16 are reversed. Even when it is in phase, it is regulated that the circuit breaker 14A for wiring is in an energized state. Therefore, it is possible to effectively prevent the circuit breaker 14A from being energized when the wiring to the hitless power supply switching device 1A is incorrect.

The technical scope of the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. For example, in the above-described embodiment, the configuration including the abnormality lamp 32 that lights up when the wiring circuit breaker 31 is in the cut-off state has been described, but the configuration is not limited to this. For example, a configuration including a buzzer or the like that emits an alarm sound or the like when the circuit breaker 31 for wiring is in the cut-off state may be employed. Alternatively, another known alarm device may be provided to notify the worker that the circuit breaker 31 for wiring is in the cut-off state. Alternatively, a configuration including a communication interface or the like that notifies an external management server or the like of a signal via a communication line and notifies an administrator or the like that the circuit breaker for wiring 31 is in the cut-off state may be used.

Furthermore, the present invention is not limited to the above-described embodiments as long as it conforms to the gist of the disclosure described in the above-described embodiments. Therefore, in the configuration in which at least two of the above-described embodiments are combined, or in the above-described embodiments, any one of the illustrated constituent elements or the constituent elements described with reference numerals is abolished. It may be a configuration that is

1, 1A Uninterruptible power supply switching device 2A, 2B Commercial power supply 3A, 3B Input panel 4A, 4B Uninterruptible power supply 5 Distribution board 6a to 6c ICT device 11A, 11B Non-trip switch 12A, DESCRIPTION OF SYMBOLS 12B... Circuit breaker for wiring 13... Switching part 14, 14A... Circuit breaker for wiring 15A, 15B... Input part 16... Output part 17a, 17b... External power supply terminal 20... Phase abnormality detection part 21, 22... Transformer 23... Voltage detection Part 24a, 24b, 26a, 26b... Voltage input part 28a, 28b, 29a, 29b... Wiring cable 31... Wiring circuit breaker 32... Abnormal lamp 33A, 33B, 34... Negative phase detector 41A, 41B... Branch board 44a, 44b, 46a, 46b... Voltage output section 51, 52, 53, 54, 55... Cable

Claims (4)

An uninterrupted power supply switching device used for switching a power supply device that supplies power to a load,
a first connection portion to which a first power supply device is connected; a second connection portion to which a second power supply device different from the first power supply device is connected;
a third connection portion to which the load is connected;
a switching unit for switching between a state in which power is supplied from the first power supply to the load and a state in which power is supplied to the load from the second power supply;
It is arranged between the power source side, which is the side of the first connecting portion and the second connecting portion, and the load side, which is the side of the third connecting portion, so that a current flows between the power source side and the load side. a short-circuit prevention unit that reversibly switches between an energized state in which the current flows and an interrupted state in which the current flow between the power supply side and the load side is interrupted;
a phase abnormality detection unit that detects a phase difference between a power supply side voltage that is the power supply side voltage in the short circuit prevention section and a load side voltage that is the load side voltage in the short circuit prevention section;
is disposed between the phase anomaly detector and the power supply side of the short-circuit prevention part, and cuts off the detected current when the value of the detected current flowing through the phase anomaly detector exceeds a predetermined threshold value; a protection part;
a detection unit that detects that the protection unit has cut off the detection current;
Uninterruptible power switching device with 2. The uninterruptible power switching device according to claim 1, wherein said protection unit reversibly cuts off said current. When the phase abnormality detection unit detects that the phase difference is equal to or greater than a predetermined magnitude,
The short-circuit prevention part is
A state in which switching from the cut-off state to the energized state is regulated,
The uninterrupted power switching device according to claim 1 or 2. Opposite phases are provided between the first connecting portion and the switching portion, between the second connecting portion and the switching portion, and between the third connecting portion and the short-circuit prevention portion. Equipped with a reversed-phase detector to detect,
When at least one of the reverse phase detection units detects the reverse phase,
The short-circuit prevention unit is in a state in which switching from the cut-off state to the energized state is restricted.
The uninterrupted power switching device according to any one of claims 1 to 3.

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