Vibration sensing device

Abstract

To provide a vibration sensing device which can suppress the malfunction of a switch.SOLUTION: A vibration sensing device is attached to a switch which includes: overcurrent detection means which detects an overcurrent accident at an electric path; power failure detection means which detects a power failure at the electric path; and a control device. The vibration sensing device includes: a power failure detection circuit to which an output signal of the power failure detection means is input; and a vibration detection circuit which detects vibration. When the vibration detection circuit detects vibration and the power failure detection circuit continues to detect the power failure of the electric path for a predetermined time, the vibration sensing device outputs a signal to an overcurrent detection circuit in the control device. When the overcurrent detection means detects the overcurrent accident of the electric path, the control device makes a switch body in a trip operation ready state. The control device controls to perform the trip operation of the switch body when the power failure of the electric path is detected by the power failure detection means in addition to the detection of an overcurrent accident by the overcurrent detection means, or when the power failure of the electric path is detected by the power failure detection means while a signal is output from the vibration sensing device to the overcurrent detection circuit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This specification discloses a technique relating to a vibration sensing device attached to a switch that opens and closes an electric circuit. [Background technology]

[0002] Patent Document 1 discloses a switch that can prevent secondary disasters, such as fires, caused by energization of electrical equipment of an electric power consumer after the power supply is resumed when a power outage occurs due to a disaster such as an earthquake. The switch of Patent Document 1 does not trip (does not open) the switch when an overcurrent accident occurs in an electric circuit, but keeps the tripped state in a standby state. The switch then trips (opens) the switch when a power outage is detected by a power outage detection means, or when vibration is detected by a vibration detection means and a power outage is detected by the power outage detection means. In other words, the switch of Patent Document 1 does not trip when vibration is detected by the vibration detection means alone, but trips when a power outage is detected together with vibration. This prevents the switch from tripping (misoperating) when vibrations that are not caused by a disaster such as an earthquake are detected, such as when a large vehicle passes around the switch and causes vibrations. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-273389 Summary of the Invention [Problem to be solved by the invention]

[0004] The switch disclosed in Patent Document 1 trips when both a power outage and vibration are detected. This prevents the switch from malfunctioning (false opening). However, if the voltage of the electric circuit temporarily drops coincidentally with the detection of vibration, the switch may determine that a power outage has been detected along with the vibration and trip. A temporary voltage drop in an electric circuit refers to a voltage drop of approximately 90% or less of the normal voltage for approximately two seconds or less, and is sometimes referred to as a "voltage drop." In other words, the switch disclosed in Patent Document 1 may malfunction by tripping even when a tripping operation is unnecessary if a special condition occurs, such as the coincidence of an extremely short power outage (voltage drop) that is not generally considered a power outage and the detection of vibration that is not caused by a disaster such as an earthquake. Therefore, there is a demand for a vibration sensing device that can prevent the switch from malfunctioning. The present specification aims to provide a vibration sensing device that can prevent the switch from malfunctioning. [Means for solving the problem]

[0005] One embodiment of the vibration sensing device disclosed herein is attached to a switch equipped with an overcurrent detection means for detecting an overcurrent fault in an electric circuit, a power outage detection means for detecting a power outage in the electric circuit, and a control device. The vibration sensing device may include a power outage detection circuit to which an output signal from the power outage detection means is input, and a vibration detection circuit for detecting vibration. The vibration sensing device may also output a signal to an overcurrent detection circuit in the control device when the vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit for a predetermined period of time. By attaching this vibration sensing device to the switch, the control device can prepare to trip the switch body when the overcurrent detection means detects an overcurrent fault in the electric circuit, and can trip the switch body when the overcurrent detection means detects an overcurrent fault and the power outage detection means detects a power outage in the electric circuit, or when the vibration sensing device outputs a signal to the overcurrent detection circuit and the power outage detection means detects a power outage in the electric circuit.

[0006] Another embodiment of the vibration sensing device disclosed in this specification is attached to a switch equipped with overcurrent detection means for detecting overcurrent faults in an electric circuit, ground fault detection means for detecting ground faults in the electric circuit, power outage detection means for detecting power outages in the electric circuit, and a control device. The vibration sensing device may include a power outage detection circuit to which an output signal from the power outage detection means is input, and a vibration detection circuit for detecting vibrations. The vibration sensing device may also output a signal to an overcurrent detection circuit in the control device when the vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit for a predetermined period of time. By attaching this vibration sensing device to a switch, the control device can prepare for tripping of the switch main body when the overcurrent detection means detects an overcurrent fault in the electric circuit, and trip the switch main body in any of the following cases (1) to (3): (1) When the overcurrent detection means detects an overcurrent fault and the power outage detection means detects a power outage in the electric circuit; (2) When the ground fault detection means detects a ground fault and the overcurrent detection means does not detect an overcurrent fault. (3) When a signal is output from the vibration sensing device to the overcurrent detection circuit and a power outage in the electrical circuit is detected by the power outage detection means.

[0007] Another embodiment of the vibration sensing device disclosed in this specification is attached to a switch equipped with a ground fault detection means for detecting a ground fault in an electric circuit, a vibration sensing means for detecting vibrations, and a control device. The vibration sensing device may include a power outage detection circuit to which a signal indicating a power outage has occurred in the electric circuit is input, and a vibration detection circuit for detecting vibrations. By attaching this vibration sensing device to the switch, the control device can trip the switch body when the ground fault detection means detects a ground fault, or when the vibration sensing device detects vibrations and the power outage detection means detects a power outage in the electric circuit for a predetermined period of time. [Brief explanation of the drawings]

[0008] [Figure 1] A schematic diagram of a switch is shown. [Figure 2] 1 shows a block diagram of a vibration sensing device according to a first embodiment. [Figure 3] FIG. 10 shows a block diagram of a vibration sensing device according to a second embodiment. [Figure 4] FIG. 10 shows a block diagram of a vibration sensing device according to a third embodiment. [Figure 5] FIG. 10 shows a block diagram of a vibration sensing device according to a fourth embodiment. [Figure 6] FIG. 10 shows a block diagram of a vibration sensing device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The vibration sensing device disclosed in this specification may include a power failure detection circuit, a vibration detection circuit, and a circuit (or group of circuits) to which output signals from the power failure detection circuit and the vibration detection circuit are input. The power failure detection circuit may be connected to a transformer for a control power supply of a switch. When the power failure detection circuit is connected to the transformer for a control power supply of a switch, the power failure detection circuit can detect a power failure in the electrical circuit when a power failure occurs in the electrical circuit. The output section of the circuit to which the output signals from the power failure detection circuit and the vibration detection circuit are input may be connected to an overcurrent detection circuit in the control device. Furthermore, the circuit to which the output signals from the power failure detection circuit and the vibration detection circuit are input may delay the output signal from the power failure detection circuit and output a signal to the overcurrent detection circuit (when the output signal from the power failure detection circuit has been input continuously for a predetermined period of time).

[0010] An example of a circuit (circuit group) that delays the output signal of a power failure detection circuit and outputs a signal to an overcurrent detection circuit is an operation delay timer circuit that outputs a signal when a signal is continuously input for a predetermined period of time. Alternatively, in addition to the operation delay timer circuit, a signal output circuit that outputs a signal when the output signal of the operation delay timer circuit is continuously input for a predetermined period of time may be provided. Another example of a circuit (circuit group) that delays the output signal of a power failure detection circuit and outputs a signal to an overcurrent detection circuit is a combination of a power failure continuation confirmation circuit and an AND circuit to which the output signal of the power failure continuation confirmation circuit and the output signal of the vibration detection circuit are input when the output signal of the power failure detection circuit is continuously input for a predetermined period of time. Alternatively, in addition to the power failure continuation confirmation circuit and the AND circuit, a signal output circuit that outputs a signal when the output signal of the AND circuit is continuously input for a predetermined period of time may be provided. Another example of a circuit (circuit group) that delays the output signal of a power failure detection circuit and outputs a signal to an overcurrent detection circuit is a combination of an AND circuit to which the output signal of the power failure detection circuit and the output signal of the vibration detection circuit are input, and a signal output circuit that outputs a signal when the output signal of the AND circuit is continuously input for a predetermined period of time.

[0011] When the vibration sensing device is attached to a switch, the switch prepares the tripping operation of the switch body and closes the circuit when the overcurrent detection means detects an overcurrent fault in the electrical circuit. The switch body then trips when both an overcurrent fault and a power outage in the electrical circuit are detected by the power outage detection means. The switch body also trips when vibration is detected by the vibration sensing means and a power outage in the electrical circuit continues for a predetermined period of time by the power outage detection circuit. That is, when the vibration sensing device is attached to a switch, even if vibration is detected by the vibration detection circuit, the switch body does not trip unless the power outage detection circuit detects a power outage in the electrical circuit for a predetermined period of time. This prevents tripping when the voltage in the electrical circuit temporarily drops (in the case of a so-called voltage sag). The vibration sensing device disclosed in this specification can suppress erroneous tripping of the switch when the electrical circuit momentarily drops (when no tripping is required). [Example]

[0012] With reference to FIG. 1, a high-voltage air switch 100 will be outlined. The high-voltage air switch 100 is an example of a switch, and is an overcurrent lock type (SOG type) high-voltage air switch. The high-voltage air switch 100 includes a switch body 50, a control device 30 that controls the operation of the switch body 50, and a vibration sensor 10. The switch body 50 and the control device 30 are connected by a cable. The switch body 50 is installed at the top of a utility pole (not shown), and the control device 30 is installed at the bottom of the utility pole. The vibration sensor 10 is connected to the control device 30 by wiring 92, 94. More specifically, the vibration sensor 10 is connected to the output part of a control power supply transformer 80 and the input part of an overcurrent detection circuit 36, which will be described later. First, the internal configuration of the switch body 50 will be described.

[0013] (Structure of the switch body) The switch body 50 is provided on an electric circuit 52. More specifically, the switch body 50 is connected to an electric power supply side (power supply side) electric circuit 52a and a consumer side (load side) electric circuit 52b, electrically connecting the two (closing the electric circuit 52). The electric circuit 52 has an R phase, an S phase, and a T phase. On the electric circuit 52, a zero-phase current transformer 58, a switching unit 54, a control power supply transformer 80, and a current detection unit 60 are arranged in this order from the power supply side to the load side.

[0014] The zero-phase-sequence current transformer 58 detects a zero-phase-sequence current (ground fault current) occurring in the electric circuit 52. Both ends of the zero-phase-sequence current transformer 58 are connected to the control device 30. As will be described in detail later, both ends of the zero-phase-sequence current transformer 58 are connected to terminals 90d of a terminal block 90 provided in the control device 30, and are connected to the ground fault detection circuit 31 (see FIG. 2). When the zero-phase-sequence current is detected by the zero-phase-sequence current transformer 58, a detection signal is output to the control device 30 (ground fault detection circuit 31).

[0015] The switching unit 54 includes switches 54r, 54s, and 54t. The switches 54r, 54s, and 54t are respectively provided on the R phase, S phase, and T phase of the electric circuit 52. When the switching unit 54 is opened, the electric circuit 52 is opened, and when the switching unit 54 is closed, the electric circuit 52 is closed.

[0016] The control power supply transformer 80 has two coils with different numbers of turns. The primary coil is connected to two phases (S-phase and T-phase) of the electric circuit 52. The secondary coil is connected to a terminal 90b of a terminal block 90 provided in the control device 30, and is connected to the power supply circuit 33 and the energy storage circuit 35 (see FIG. 2). A wiring 92 is also connected to the terminal 90b. The wiring 92 is connected to a terminal 96b of a terminal block 96 provided in the vibration sensing device 10, and is connected to the power supply circuit 16 (see FIG. 2). That is, the secondary coil is also connected to the power supply circuit 16 in the vibration sensing device 10. The control power supply transformer 80 can generate power to drive the circuits in the control device 30. The high-voltage air contactor 100 can secure power to drive the circuits in the control device 30 and the vibration sensing device 10 by utilizing the voltage of the electric circuit 52, so it is possible to omit providing a separate power supply just for driving the circuits in the control device 30 and the vibration sensing device 10.

[0017] The current detection unit 60 includes current transformers 60r and 60t. As described above, the current detection unit 60 is provided downstream (on the consumer-side electric circuit 52b side) of the switching unit 54. Therefore, the current transformers 60r and 60t can detect the load currents flowing through the R phase and T phase of the electric circuit 52, respectively. The current detection unit 60 is connected to a microswitch 70. The microswitch 70 is a double-throw type and includes a normally closed contact 72, a normally open contact 74, and a common contact 76. The normally closed contact 72 and the common contact 76 are connected to a terminal 90a of a terminal block 90 provided in the control device 30, and are connected to the overcurrent detection circuit 36 ​​(see FIG. 2). A wire 94 is also connected to the terminal 90a. The wire 94 is connected to a terminal 96a of a terminal block 96 provided in the vibration sensing device 10, and is connected to the operation delay timer circuit 4 (see FIG. 2). In other words, the current detection unit 60 is also connected to the operation delay timer circuit 4 in the vibration sensing device 10.

[0018] When the current detection unit 60 (current transformers 60r, 60t) detects a current equal to or greater than the overcurrent detection value, the microswitch 70 connects the normally closed contact 72 and the common contact 76 (the normally closed contact 72 closes). When the normally closed contact 72 and the common contact 76 are connected, a detection signal is output to the control device 30. The normally closed contact 72 is also connected to a trip coil 56. The trip coil 56 is connected to a terminal 90c of a terminal block 90 provided in the control device 30, and is also connected to the normally open contact 41 (see FIG. 2). The trip coil 56 trips (opens) the switches 54r, 54s, and 54t of the opening / closing unit 54.

[0019] The control device 30 will be described with reference to Fig. 2. A plurality of circuits and normally open contacts 41 are provided within the control device 30. The ground fault detection circuit 31 is connected to the zero-phase-sequence current transformer 58 via terminal 90d of the terminal block 90 (see also Fig. 1), and outputs a ground fault detection signal to the operation determination circuit 32 when it detects an output signal from the zero-phase-sequence current transformer 58.

[0020] The power supply circuit 33 is connected to the control power supply transformer 80 via terminal 90b of the terminal block 90 (see also FIG. 1), and smooths the line voltage between the S phase and the T phase of the electric circuit 52 and converts it into a DC voltage. The power supply circuit 33 is also connected to a power outage detection circuit 34. Therefore, when a power outage occurs in the electric circuit 52, the power supply from the power supply circuit 33 stops, and the power outage detection circuit 34 can determine that the electric circuit 52 has experienced a power outage. When the power outage detection circuit 34 determines that the electric circuit 52 has experienced a power outage, it outputs a power outage detection signal to the AND circuit 37. Although not shown, the DC voltage converted by the power supply circuit 33 is also supplied to circuits other than the power outage detection circuit 34 within the control device 30.

[0021] The energy storage circuit 35 is also connected to the control power supply transformer 80 via terminal 90b of the terminal block 90. ​​The energy storage circuit 35 stores the line voltage between the S phase and the T phase of the electric circuit 52 as a power source for exciting the trip coil 56 (see also FIG. 1). A normally open contact 41 is provided between the energy storage circuit 35 and the trip coil 56. When the normally open contact 41 closes, the power stored in the energy storage circuit 35 is supplied to the trip coil 56, which is excited and causes the switching unit 54 to trip.

[0022] The overcurrent detection circuit 36 ​​is connected to the current detection unit 60 via terminal 90a of the terminal block 90 (see also FIG. 1), and when an overcurrent detection signal is input from the current detection unit 60, it outputs an abnormality detection signal to the AND circuit 37 and the lock circuit 38. The overcurrent detection circuit 36 ​​also receives the output signal of the operation delay circuit 4 in the vibration sensor 10. When the abnormality detection signal is input, the lock circuit 38 outputs a lock signal to the operation determination circuit 32 to lock the tripping operation of the switching unit 54. In other words, when a lock signal is input to the lock circuit 38, the opening operation of the switching unit 54 is prohibited.

[0023] When a ground fault detection signal is input from the ground fault detection circuit 31, the operation determination circuit 32 determines whether or not a lock signal is input from the lock circuit 38. When a lock signal is not input, the operation determination circuit 32 outputs a trip operation permission signal to the OR circuit 39, and when a lock signal is input, the operation determination circuit 32 does not output a trip operation permission signal to the OR circuit 39.

[0024] The AND circuit 37 outputs a trip operation permission signal to the OR circuit 39 when it receives both the power failure detection signal from the power failure detection circuit 34 and the abnormality detection signal from the overcurrent detection circuit 36. That is, the AND circuit 37 does not output a trip operation permission signal to the OR circuit 39 when it receives only the power failure detection signal from the power failure detection circuit 34 or only the abnormality detection signal from the overcurrent detection circuit 36. The OR circuit 39 outputs a trip operation request signal to the operation output circuit 40 when it receives the trip operation permission signal from the operation determination circuit 32 or the trip operation permission signal from the AND circuit 37. The OR circuit 39 also outputs a trip operation request signal to the operation output circuit 40 when it receives trip operation permission signals from both the operation determination circuit 32 and the AND circuit 37.

[0025] When a trip operation request signal is input from the OR circuit 39, the operation output circuit 40 excites an excitation coil (not shown) to close the normally open contact 41. As a result, power is supplied from the energy storage circuit 35 to the trip coil 56 via the terminal 90c of the terminal block 90, and the switching unit 54 is tripped.

[0026] (Structure of vibration sensing device: First embodiment) The vibration sensing device 10 is provided with a power supply circuit 16, a power outage detection circuit 2, a vibration sensor 14, a vibration detection circuit 12, a reset timer circuit 8, a vibration detection test circuit 6, and an operation delay timer circuit 4. When the vibration sensor 14 detects vibrations of a predetermined value or greater, it outputs a detection signal to the vibration detection circuit 12. The vibration sensor 14 is adjusted to output a detection signal when it detects vibrations corresponding to a seismic intensity of 5, for example. The vibration sensing device 10 can be installed at the bottom of a utility pole, similar to the control device 30. The vibration sensing device 10 can be installed above, below, to the left, or to the right of the control device 30.

[0027] When a detection signal is input from the vibration sensor 14, the vibration detection circuit 12 outputs a vibration detection signal to the reset timer circuit 8 and the operation delay timer circuit 4. The reset timer circuit 8 starts counting when the input of the vibration detection signal from the vibration detection circuit 12 stops, and outputs a reset signal to the vibration sensor 14 when a predetermined time (e.g., 5 seconds) has elapsed. When the reset signal is input from the reset timer circuit 8, the vibration sensor 14 returns to its initial state. The predetermined time for the reset timer circuit 8 is arbitrary and may be, for example, 1 minute, 10 minutes, or 1 hour.

[0028] The power supply circuit 16 is connected to a control power supply transformer 80 (see also FIG. 1 ). Specifically, the power supply circuit 16 is connected to the control power supply transformer 80 via a connecting wire 92 that connects a terminal 96b of a terminal block 96 in the vibration sensing device 10 to a terminal 90b of a terminal block 90 in the control device 30. The power supply circuit 16 smoothes the line voltage between the S phase and the T phase of the electric circuit 52 and converts it into a DC voltage. The power supply circuit 16 is also connected to a power outage detection circuit 2. When a power outage occurs in the electric circuit 52, the power outage detection circuit 2 stops supplying power from the power supply circuit 16 and outputs a power outage detection signal to the operation delay timer circuit 4. That is, the vibration detection signal from the vibration detection circuit 12 and the power outage detection signal from the power outage detection circuit 2 are input to the operation delay timer circuit 4. The DC voltage converted by the power supply circuit 16 is also supplied to circuits other than the power outage detection circuit 2 in the vibration sensing device 10.

[0029] The operation delay timer circuit 4 is connected to the overcurrent detection circuit 36. Specifically, the operation delay timer circuit 4 is connected to the overcurrent detection circuit 36 ​​via a connecting wire 94 that connects a terminal 96a of a terminal block 96 in the vibration sensor 10 to a terminal 90a of a terminal block 90 in the control device 30. The operation delay timer circuit 4 delays the vibration detection signal and the power outage detection signal and outputs the delayed signals to the overcurrent detection circuit 36. Specifically, the operation delay timer circuit 4 outputs a signal to the overcurrent detection circuit 36 ​​when both the vibration detection signal and the power outage detection signal are continuously input for a predetermined time (e.g., 2 seconds). In other words, the operation delay timer circuit 4 does not output a signal to the overcurrent detection circuit 36 ​​if the input signal from the vibration detection circuit 12 or the power outage detection circuit 34 is less than the predetermined time. The predetermined time of the operation delay timer circuit 4 is arbitrary and may be, for example, 1 second, 3 seconds, or 5 seconds. Furthermore, after the overcurrent detection circuit 36 ​​outputs a signal to the AND circuit 37 and the lock circuit 38, the operation delay timer circuit 4 returns to the initial state.

[0030] The vibration detection test circuit 6 can input a test signal to the vibration detection circuit 12. That is, the vibration detection test circuit 6 can input a pseudo signal for confirming vibration detection to the vibration detection circuit 12. Furthermore, by providing the vibration detection test circuit 6, it is possible to check whether or not the vibration sensing device 10 is malfunctioning during periodic inspection of the control device 10.

[0031] Since the vibration sensing device 10 can be easily connected to an existing control device 30 via a connecting wire, it is also possible to convert an already installed high-voltage air switch (a high-voltage air switch without a vibration sensing function) into a high-voltage air switch that can respond to disasters such as earthquakes.

[0032] (Operation of high-voltage air switch) The operation of the high-voltage air contactor 100 will be described below. First, a case where a ground fault occurs in the electric circuit 52 will be described. When a ground fault occurs in the electric circuit 52, a ground fault detection signal is input from the ground fault detection circuit 31 to the operation determination circuit 32. As described above, the operation determination circuit 32 determines whether or not a lock signal is input from the lock circuit 38. When an overcurrent detection signal is input from the overcurrent detection circuit 36, the lock circuit 38 outputs a lock signal to the operation determination circuit 32. In other words, when an overcurrent detection signal is not input from the overcurrent detection circuit 36, the lock circuit 38 does not output a lock signal to the operation determination circuit 32. Therefore, when a current equal to or greater than the overcurrent detection threshold does not flow in the electric circuit 52, the operation determination circuit 32 outputs a trip operation permission signal to the OR circuit 39, and the OR circuit 39 outputs a trip operation request signal to the operation output circuit 40, causing the normally open contacts 41 to close and the trip coil 56 to perform a trip operation of the switching unit 54.

[0033] On the other hand, when a current equal to or greater than the overcurrent detection threshold flows in the electric circuit 52 (the overcurrent detection circuit 36 ​​outputs an abnormality detection signal to the lock circuit 38), a lock signal is output from the lock circuit 38 to the operation determination circuit 32, and therefore the tripping operation of the switching unit 54 is locked (the tripping operation is set to a preparation state). When a power outage occurs in the electric circuit 52, the power outage detection circuit 34 outputs a power outage detection signal to the AND circuit 37, and then the switching unit 54 performs a tripping operation. This prevents the switching unit 54 from being opened while an overcurrent is flowing in the electric circuit 52, and makes it possible to prevent a failure of the high-voltage air contactor 100 (switch body 50).

[0034] Next, we will explain what happens when an overcurrent fault occurs in the electric circuit 52 and causes a power outage in the electric circuit 52. When an overcurrent fault occurs in the electric circuit 52, the overcurrent detection circuit 36 ​​outputs an abnormality detection signal to the AND circuit 37 and the lock circuit 38. Therefore, when a current equal to or greater than the overcurrent detection threshold flows through the electric circuit 52, the lock circuit 38 outputs a lock signal to the operation determination circuit 32, and the trip operation of the switching unit 54 is locked. When a power outage occurs in the electric circuit 52, the power outage detection circuit 34 outputs a power outage detection signal to the AND circuit 37. When the abnormality detection signal from the current detection unit 60 and the power outage detection signal from the power outage detection circuit 34 are input to the AND circuit 37, the AND circuit 37 outputs a trip operation permission signal to the OR circuit 39. As a result, the OR circuit 39 outputs a trip operation request signal to the operation output circuit 40, the normally open contact 41 closes, and the trip coil 56 trips the switching unit 54. The switching unit 54 is prevented from being opened when an overcurrent is flowing through the electric circuit 52, and breakdown of the high voltage air switch 100 (switch body 50) can be prevented.

[0035] Next, we will explain what happens when a power outage occurs in the electric circuit 52 and the vibration detection circuit 12 (vibration sensor 14) detects vibrations equal to or greater than a predetermined value. This situation can typically occur when a power outage occurs due to an earthquake. When the power outage detection circuit 2 detects a power outage in the electric circuit 52, a power outage detection signal is output to the operation delay timer circuit 4. Furthermore, when the power outage detection circuit 2 detects a power outage in the electric circuit 52, the power outage detection circuit 34 in the control device 30 also detects a power outage in the electric circuit 52. Therefore, when a power outage occurs in the electric circuit 52, a power outage detection signal is output to the AND circuit 37 and the operation delay timer circuit 4.

[0036] When both the vibration detection signal and the power outage detection signal are continuously input for a predetermined time, the operation delay timer circuit 4 outputs a signal to the overcurrent detection circuit 36 ​​via the terminal 96a of the terminal block 96, the connecting wire 94, and the terminal 90a of the terminal block 90. ​​As described above, when a signal is input to the overcurrent detection circuit 36, the overcurrent detection circuit 36 ​​outputs a signal to the AND circuit 37 and the lock circuit 38. Therefore, when a signal is input from the operation delay timer circuit 4 to the overcurrent detection circuit 36, both the power outage detection signal from the power outage detection circuit 34 and the output signal of the overcurrent detection circuit 36 ​​are input to the AND circuit 37. In other words, only when the power outage detection circuit 2 continuously outputs the power outage detection signal for a predetermined time are both the power outage detection signal from the power outage detection circuit 34 and the signal from the operation delay timer circuit 4 input to the AND circuit 37. In other words, if the voltage of the electrical circuit 52 temporarily drops (the voltage drops for less than a predetermined time), a power outage detection signal is input from the power outage detection circuit 34 to the AND circuit 37, but a signal from the overcurrent detection circuit 36 ​​(operation delay timer circuit 4) is not input to the AND circuit 37.

[0037] When both the power outage detection signal from the power outage detection circuit 34 and the signal from the operation delay timer circuit 4 are input to the AND circuit 37, the AND circuit 37 outputs a trip operation permission signal to the OR circuit 39, the OR circuit 39 outputs a trip operation request signal to the operation output circuit 40, the normally open contacts 41 close, and the trip coil 56 performs the trip operation of the switching unit 54. In other words, when a power outage occurs in the electric circuit 52 due to the occurrence of an earthquake, the switching unit 54 is opened. As a result, when power is restored to the power system, power is prevented from being supplied to the load equipment, and the occurrence of secondary disasters such as fires can be prevented.

[0038] On the other hand, if the voltage in the electric circuit 52 only drops temporarily, the signal from the overcurrent detection circuit 36 ​​(action delay timer circuit 4) is not input to the AND circuit 37, and the switching unit 54 does not trip. Therefore, in the high-voltage air switchgear 100, it is possible to prevent the switching unit 54 from tripping when an extremely short-term power outage (instantaneous voltage drop) that is not generally called a power outage occurs and vibration that is not a disaster such as an earthquake is detected at the same time. The switchgear 10 equipped with the vibration sensing device 10 can prevent malfunctions such as the switching unit 54 tripping when it is not necessary to do so.

[0039] (Modifications of the vibration sensing device: Second to fifth embodiments) The high voltage air contactors 100a to 100d will be described below with reference to Figures 3 to 6. The high voltage air contactors 100a to 100d are modified examples of the high voltage air contactor 100. The high voltage air contactors 100a to 100d have vibration sensors 10a to 10d attached thereto which have a different structure from the vibration sensor 10 attached to the high voltage air contactor 100. For the high voltage air contactors 100a to 100d, only the structure of the vibration sensors 10a to 10d will be described. Furthermore, for the vibration sensors 10a to 10d, the same reference numbers as those attached to the vibration sensor 10 will be used to designate the same components as those of the vibration sensor 10, and descriptions thereof may be omitted.

[0040] (Second Example) As shown in FIG. 3, the vibration sensing device 10a of the high-voltage air switch 100a is provided with a power supply circuit 16, a power outage detection circuit 2, a vibration sensor 14, a vibration detection circuit 12, a reset timer circuit 8, a vibration detection test circuit 6, a power outage continuation confirmation circuit 20, and an AND circuit 22. A power outage detection signal is input from the power outage detection circuit 2. The power outage continuation confirmation circuit 20 delays the power outage detection signal and outputs it to the AND circuit 22. Specifically, the power outage continuation confirmation circuit 20 outputs the power outage detection signal to the AND circuit 22 when the power outage detection signal has been input continuously for a predetermined time (e.g., 2 seconds). The predetermined time for the power outage continuation confirmation circuit 20 to detect the power outage detection signal is arbitrary and may be, for example, 1 second, 3 seconds, or 5 seconds.

[0041] The AND circuit 22 also receives a vibration detection signal from the vibration detection circuit 12. When both the power outage detection signal from the power outage continuation confirmation circuit 20 and the vibration detection signal from the vibration detection circuit 12 are input to the AND circuit 22, the AND circuit 22 outputs a signal to the overcurrent detection circuit 36. In other words, if the power outage detection signal input from the power outage detection circuit 20 to the power outage continuation confirmation circuit 20 is for less than a predetermined time, no signal is output from the AND circuit 22 to the overcurrent detection circuit 36, and no tripping operation is performed in the switching unit 54. The high-voltage air switchgear 100a equipped with the vibration sensing device 10a can also prevent malfunctions such as tripping of the switching unit 54 when it is not necessary.

[0042] (Third Example) As shown in FIG. 4, the vibration sensing device 10b of the high-voltage air switchgear 100b includes a power supply circuit 16, a power outage detection circuit 2, a vibration sensor 14, a vibration detection circuit 12, a reset timer circuit 8, a vibration detection test circuit 6, an AND circuit 22, and a signal output circuit 24. The AND circuit 22 receives a power outage detection signal from the power outage detection circuit 2 and a vibration detection signal from the vibration detection circuit 12. When both the power outage detection signal and the vibration detection signal are received, the AND circuit 22 outputs a signal to the overcurrent detection circuit 36. The signal output circuit 24 delays the signal from the AND circuit 22 and outputs the delayed signal to the overcurrent detection circuit 36. Specifically, the signal output circuit 24 outputs a signal to the overcurrent detection circuit 36 ​​when the signal from the AND circuit 22 is continuously received for a predetermined time (e.g., two seconds). The predetermined time for the signal output circuit 24 to detect the signal from the AND circuit 22 is arbitrary and may be, for example, one second, three seconds, or five seconds.

[0043] In the high voltage air switch 100b, if the power failure detection signal input from the power failure detection circuit 2 to the AND circuit 22 is for less than a predetermined time, no signal is output from the signal output circuit 24 to the overcurrent detection circuit 36, and no signal from the overcurrent detection circuit 36 ​​is input to the AND circuit 37. Therefore, the high voltage air switch 100b can also prevent a malfunction such as a tripping operation being performed when a tripping operation of the switching unit 54 is not required.

[0044] (Fourth Example) As shown in FIG. 5, the vibration sensing device 10c of the high-voltage air contactor 100c is provided with a power supply circuit 16, a power outage detection circuit 2, a vibration sensor 14, a vibration detection circuit 12, a reset timer circuit 8, a vibration detection test circuit 6, an operation delay timer circuit 4, and a signal output circuit 24. The vibration sensing device 10c can also be considered to have a structure in which the output signal of the operation delay timer circuit 4 of the vibration sensing device 10 is input to the signal output circuit 24 (see also FIG. 2). In the high-voltage air contactor 100c, the operation delay timer circuit 4 delays the power outage detection signal from the power outage detection circuit 2, and the signal output circuit 24 further delays the output signal of the operation delay timer circuit 4. Therefore, the high-voltage air contactor 100c can more reliably prevent malfunctions such as tripping of the switching unit 54 when it is not necessary.

[0045] (Fifth Example) As shown in FIG. 6, the vibration sensing device 10d of the high-voltage air contactor 100d is provided with a power supply circuit 16, a power outage detection circuit 2, a vibration sensor 14, a vibration detection circuit 12, a reset timer circuit 8, a vibration detection test circuit 6, a power outage continuation confirmation circuit 20, an AND circuit 22, and a signal output circuit 24. The vibration sensing device 10d can also be considered to have a structure in which the output signal of the AND circuit 22 of the vibration sensing device 10a is input to the signal output circuit 24 (see also FIG. 3). Alternatively, the vibration sensing device 10d can also be considered to have a structure in which the power outage detection signal from the power outage detection circuit 2 is input to the AND circuit 22 via the power outage continuation confirmation circuit 20 (see also FIG. 4). In the high-voltage air contactor 100d, the power outage detection signal from the power outage detection circuit 2 is delayed by the power outage continuation confirmation circuit 20, and the output signal of the AND circuit 22 is further delayed by the signal output circuit 24. Therefore, the high voltage air contactor 100d can also more reliably prevent a malfunction such as the switching unit 54 performing a tripping operation when the tripping operation is not required.

[0046] (Variation 1 of high-voltage air switch) Although not shown, the high voltage air switchgear of the first modification is the same as the high voltage air switchgears 100, 100a, 100b, 100c and 100d described above, except that the zero-phase-sequence current transformer 58 is omitted from the switchgear main body 50 (see FIG. 1), and the ground fault detection circuit 31, operation determination circuit 32, lock circuit 38 and OR circuit 39 are omitted from the control device 30 (see FIGS. 2 to 6). In other words, the high voltage air switchgear of the first modification is a high voltage air switchgear (switchgear main body and control device) having only an overcurrent protection function (SO function) and no ground fault function (GR function), to which any of the vibration sensing devices 10, 10a, 10b, 10c and 10d is connected. This type of high voltage air switchgear can also prevent a malfunction such as a tripping operation of the switching unit 54 when it is not required.

[0047] (Variation 2 of high-voltage air switch) Although not shown, the high voltage air circuit breaker of Modification 2 is configured by omitting the current detection unit 60 from the switch body 50 of the above-mentioned high voltage air circuit breakers 100, 100a, 100b, 100c, and 100d, omitting the overcurrent detection circuit 36, AND circuit 37, lock circuit 38, and operation determination circuit 32 from the control device 30, and connecting the connecting wire 94 to a terminal 90d of a terminal block 90 in the control device 30 (see FIGS. 1 to 6). That is, the high voltage air circuit breaker of Modification 2 is configured by connecting any of the vibration sensing devices 10, 10a, 10b, 10c, and 10d to a high voltage air circuit breaker (switch body and control device) having only a ground fault function (GR function) and no overcurrent protection function (SO function). This type of high voltage air circuit breaker can also prevent a malfunction such as the switching unit 54 tripping when it is not required.

[0048] (Other variations) Instead of an overcurrent lock type (SOG type) high-voltage air circuit breaker (see Figure 1), any of the vibration sensors 10, 10a, 10b, 10c, and 10d may be connected to an overcurrent energy storage trip with earth fault energy storage trip type (SOSG type) high-voltage air circuit breaker. Also, the vibration sensors 10, 10a, 10b, 10c, and 10d may be equipped with a lighting lamp that lights up when vibration is detected.

[0049] Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and variations of the specific examples exemplified above. Furthermore, the technical elements described in this specification or drawings exhibit technical utility alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technology exemplified in this specification or drawings can achieve multiple objectives simultaneously, and achieving one of these objectives itself has technical utility. [Explanation of symbols]

[0050] 2: Power outage detection circuit 10: Vibration sensing device 14: Vibration detection circuit 30: Control device 34: Power outage detection means 54:Electric circuit 60: Overcurrent detection means 100: Switch

Claims

1. A vibration sensing device attached to a control device connected to a switch having an overcurrent detection means for detecting an overcurrent fault in an electric circuit by detecting the load current of the electric circuit, and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device a power outage detection circuit to which an output signal of the power outage detection means is input; a vibration detection circuit for detecting vibration; an operation delay means for receiving output signals from the power failure detection circuit and the vibration detection circuit; The operation delay means is The vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit. When both the output signal of the power outage detection circuit and the output signal of the vibration detection circuit are input for a predetermined time, a signal is output to the overcurrent detection circuit in the control device. The control device When the overcurrent detection means detects an overcurrent fault in the electric circuit, the switch body is set to a ready state for tripping; A vibration sensing device that trips the switch body when an overcurrent accident is detected by an overcurrent detection means and a power outage in the electrical circuit is detected by a power outage detection means, or when a signal is output from the vibration sensing device to an overcurrent detection circuit and a power outage in the electrical circuit is detected by the power outage detection means.

2. A vibration sensing device attached to a control device connected to a switch having an overcurrent detection means for detecting an overcurrent fault in an electric circuit by detecting a load current in the electric circuit, a ground fault detection means for detecting a ground fault fault in the electric circuit, and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device a power outage detection circuit to which an output signal of the power outage detection means is input; a vibration detection circuit for detecting vibration; an operation delay means for receiving output signals from the power failure detection circuit and the vibration detection circuit; The operation delay means is The vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit. When both the output signal of the power outage detection circuit and the output signal of the vibration detection circuit are input for a predetermined time, a signal is output to the overcurrent detection circuit in the control device. The control device When the overcurrent detection means detects an overcurrent fault in the electric circuit, the switch body is set to a ready state for tripping; A vibration sensing device that trips the switch body in any of the following cases (1) to (3): (1) When an overcurrent fault is detected by the overcurrent detection means and a power outage in the electrical circuit is detected by the power outage detection means (2) When a ground fault is detected by the ground fault detection means and an overcurrent fault is not detected by the overcurrent detection means (3) When a signal is output from the vibration sensor to the overcurrent detection circuit and a power outage is detected by the power outage detection means.

3. A vibration sensing device attached to a control device connected to a switch having a ground fault detection means for detecting a ground fault in an electric circuit and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device a power outage detection circuit to which a signal indicating that a power outage has occurred in the electric circuit is input from a power outage detection means; a vibration detection circuit for detecting vibration; an operation delay means for receiving output signals from the power failure detection circuit and the vibration detection circuit; The operation delay means is When both the output signal of the power failure detection circuit and the output signal of the vibration detection circuit are input for a predetermined time, a signal is output to the current detection circuit in the control device, The control device A vibration sensing device that trips the switch body when a ground fault is detected by a ground fault detection means, or when vibration is detected by a vibration sensing device and a power outage in the electrical circuit is detected by a power outage detection means, and a signal is output from an operation delay means to a current detection circuit in a control device.

4. A vibration sensing device attached to a control device connected to a switch having an overcurrent detection means for detecting an overcurrent fault in an electric circuit by detecting the load current of the electric circuit, and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device The power failure detection circuit receives an output signal from the power failure detection means, and the vibration detection circuit detects vibrations. When the vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit for a predetermined period of time, a signal is output to an overcurrent detection circuit in the control device, The control device When the overcurrent detection means detects an overcurrent fault in the electric circuit, the switch body is set to a ready state for tripping; When an overcurrent fault is detected by the overcurrent detection means and a power outage in the electric circuit is detected by the power outage detection means, or when a signal is output from the vibration sensor to the overcurrent detection circuit and a power outage in the electric circuit is detected by the power outage detection means, the switch body is tripped, The vibration sensing device further includes an AND circuit that receives output signals from the power failure detection circuit and the vibration detection circuit, and a power failure continuation confirmation means connected between the power failure detection circuit and the AND circuit, The power failure continuation confirmation means outputs a signal to the AND circuit when the output signal of the power failure detection circuit is input continuously for a predetermined time, The AND circuit is a vibration sensing device that outputs a signal to an overcurrent detection circuit in the control device when signals are input from the power outage continuation confirmation means and the vibration detection circuit.

5. A vibration sensing device attached to a control device connected to a switch having an overcurrent detection means for detecting an overcurrent fault in an electric circuit by detecting a load current in the electric circuit, a ground fault detection means for detecting a ground fault fault in the electric circuit, and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device The power failure detection circuit receives an output signal from the power failure detection means, and the vibration detection circuit detects vibrations. When the vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit for a predetermined period of time, a signal is output to an overcurrent detection circuit in the control device, The control device When the overcurrent detection means detects an overcurrent fault in the electric circuit, the switch body is set to a ready state for tripping; The vibration sensing device further includes an AND circuit that receives output signals from the power failure detection circuit and the vibration detection circuit, and a power failure continuation confirmation means connected between the power failure detection circuit and the AND circuit, The power failure continuation confirmation means outputs a signal to the AND circuit when the output signal of the power failure detection circuit is input continuously for a predetermined time, The AND circuit outputs a signal to the overcurrent detection circuit in the control device when signals from the power outage continuation confirmation means and the vibration detection circuit are input. A vibration sensing device that trips the switch body in any of the following cases (1) to (3): (1) When an overcurrent fault is detected by the overcurrent detection means and a power outage in the electrical circuit is detected by the power outage detection means (2) When a ground fault is detected by the ground fault detection means and an overcurrent fault is not detected by the overcurrent detection means (3) When a signal is output from the vibration sensor to the overcurrent detection circuit and a power outage is detected by the power outage detection means.

6. A vibration sensing device attached to a control device connected to a switch having a ground fault detection means for detecting a ground fault in an electric circuit and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device The power failure detection circuit receives a signal indicating that a power failure has occurred in the electric circuit from a power failure detection means, and a vibration detection circuit detects vibrations. The control device When a ground fault is detected by the ground fault detection means, or when vibration is detected by the vibration sensing device and a power outage in the electric circuit is detected by the power outage detection means for a predetermined period of time, the switch body is tripped, The vibration sensing device further includes an AND circuit that receives output signals from the power failure detection circuit and the vibration detection circuit, and a power failure continuation confirmation means connected between the power failure detection circuit and the AND circuit, The power failure continuation confirmation means outputs a signal to the AND circuit when the output signal of the power failure detection circuit is input continuously for a predetermined time, The AND circuit is a vibration sensing device that outputs a signal to an overcurrent detection circuit in the control device when signals are input from the power outage continuation confirmation means and the vibration detection circuit.

7. A vibration sensing device attached to a control device connected to a switch having an overcurrent detection means for detecting an overcurrent fault in an electric circuit by detecting the load current of the electric circuit, and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device The power failure detection circuit receives an output signal from the power failure detection means, and the vibration detection circuit detects vibrations. When the vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit for a predetermined period of time, a signal is output to an overcurrent detection circuit in the control device, The control device When the overcurrent detection means detects an overcurrent fault in the electric circuit, the switch body is set to a ready state for tripping; When an overcurrent fault is detected by the overcurrent detection means and a power outage in the electric circuit is detected by the power outage detection means, or when a signal is output from the vibration sensor to the overcurrent detection circuit and a power outage in the electric circuit is detected by the power outage detection means, the switch body is tripped, An AND circuit that receives output signals from the power failure detection circuit and the vibration detection circuit, and a signal output means that receives the output signal from the AND circuit, The signal output means outputs a signal to an overcurrent detection circuit in the control device when the output signal of the AND circuit is received continuously for a predetermined time.

8. A vibration sensing device attached to a control device connected to a switch having an overcurrent detection means for detecting an overcurrent fault in an electric circuit by detecting a load current in the electric circuit, a ground fault detection means for detecting a ground fault fault in the electric circuit, and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device The power failure detection circuit receives an output signal from the power failure detection means, and the vibration detection circuit detects vibrations. When the vibration detection circuit detects vibration and the power outage detection circuit detects a power outage in the electric circuit for a predetermined period of time, a signal is output to an overcurrent detection circuit in the control device, The control device When the overcurrent detection means detects an overcurrent fault in the electric circuit, the switch body is set to a ready state for tripping; An AND circuit that receives output signals from the power failure detection circuit and the vibration detection circuit, and a signal output means that receives the output signal from the AND circuit, the signal output means outputs a signal to an overcurrent detection circuit in the control device when receiving an output signal from the AND circuit continuously for a predetermined time; A vibration sensing device that trips the switch body in any of the following cases (1) to (3): (1) When an overcurrent fault is detected by the overcurrent detection means and a power outage in the electrical circuit is detected by the power outage detection means (2) When a ground fault is detected by the ground fault detection means and an overcurrent fault is not detected by the overcurrent detection means (3) When a signal is output from the vibration sensor to the overcurrent detection circuit and a power outage is detected by the power outage detection means.

9. A vibration sensing device attached to a control device connected to a switch having a ground fault detection means for detecting a ground fault in an electric circuit and a power failure detection means connected to two phases of the electric circuit and detecting a power failure in the electric circuit, The vibration sensing device The power failure detection circuit receives a signal indicating that a power failure has occurred in the electric circuit from a power failure detection means, and a vibration detection circuit detects vibrations. The control device When a ground fault is detected by the ground fault detection means, or when vibration is detected by the vibration sensing device and a power outage in the electric circuit is detected by the power outage detection means for a predetermined period of time, the switch body is tripped, An AND circuit that receives output signals from the power failure detection circuit and the vibration detection circuit, and a signal output means that receives the output signal from the AND circuit, The signal output means outputs a signal to an overcurrent detection circuit in the control device when the output signal of the AND circuit is received continuously for a predetermined time.

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