JPH0552896A - Aerial-bus-supported type apparatus for locating accident - Google Patents

Abstract

PURPOSE:To make it possible to monitor the occurrence or non-occurrence of an accident easily by supporting a current transformer and a display unit at a plurality of positions of an aerial bus line. CONSTITUTION:A current transformer 8 and a display unit 9 are provided on an aerial bus line with fixing metal fittings interposed. When an accident current is present, it is detected and determined by a driving circuit 21 and a trip coil 15 is excited. When a magnetic force of a permanent magnet 13 is canceled, a movable lever opens onto the downward direction side around a first fulcrum O1, one end of a display lever moves leftward around a second fulcrum O2, a display window 20 opens and a display of red or the like can be watched therethrough. At this time, a limit switch 18 is pushed by one end of the movable lever 14 and turned ON. When the cause at an accident point is removed and restoration is made, subsequently, the circuit 21 excites a reset plunger 19 and the lever 14 moves downward around the point O1. Therefore the magnet 13 side is shifted upward, the display lever is reset and the window 20 is shut up.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is attached to an overhead bus at a branch of a substation or a branch of a distribution line to display the presence / absence of an overhead bus accident, and protects the installation of other overhead bus accidents. When it is removed by the device and automatically restored, the unit that previously displayed the fault point is automatically reset based on the normal overhead bus current, so that the fault point can be automatically displayed and reset. And an aerial bus support type accident point locator.

[0002]

2. Description of the Related Art Conventionally, in the case of a substation premises accident, a protective device is used to judge whether the premises is inside or outside the premises, and after clarifying the accident point, a recovery operation is performed.

However, in the event of an accident on the premises, the overhead bus
Since there are a large number of branches with 6 to 20 lines, the location of the accident point is visually inspected by humans to check the appearance shape for damage. However, when the cause of burnout is due to an accident current, there are often no traces and it cannot be visually detected.

Therefore, a current transformer that is insulated from the ground for each of a plurality of branch buses in the premises can be solved, but it is not realized because it is expensive and requires a large space.

On the other hand, a number of methods have been proposed for covering with a so-called preventive diagnostic device for detecting the presence or absence of an accident in the main engine (see, for example, Japanese Patent Publication No. 62-22429).

However, since the branches at a plurality of locations on the premises bus described above are guided to the breaker / transformer of the main engine through the supporting insulators and breakers, the supporting insulators and disconnectors are simple solid insulators. Since it is inexpensive, a sensor for diagnosing an accident point at that part is difficult to be economical even if it is a cheaper and simpler system.

[0007]

Although the conventional method of locating the accident point of an overhead bus has been visually inspected by humans, when it is burnt by an accident current, there are no traces and it is often impossible to visually detect it. If a current transformer insulated from the ground is provided for each of a plurality of branch buses in the premises, the problem can be solved, but there is a problem that it is expensive and the space becomes large.

It is an object of the present invention to provide an overhead bus support type accident locator which is inexpensive, compact, does not require ground insulation, and can be attached to a large number of overhead buses.

[0009]

In order to achieve the above object, an overhead bus support type accident locating apparatus according to the present invention comprises a current transformer supported by an overhead bus via a fixing bracket, and a current transformer. The display unit is provided with a display unit that detects an accident current flowing through the overhead bus adjacent to the current transformer, displays an accident, and resets the accident display when the error is restored. A constant voltage circuit connected to the constant voltage circuit, a first threshold circuit and a second threshold circuit connected to the secondary side of the constant voltage circuit for identifying a normal current or a fault current, a first threshold circuit and a second threshold circuit. The configuration includes a plunger coil connected between the threshold circuit and the rectifier circuit, a limit switch, and a trip coil for controlling the opening / closing operation of the limit switch.

Then, a current transformer supported on the overhead bus via a fixing metal fitting to detect an alternating current, and an accident current flowing through the overhead bus adjacent to the current transformer is detected to display an accident and the accident display is reset by the restoration. The display unit includes a movable lever that rotates around a first fulcrum with a permanent magnet fixed to one end and a reset spring connected to the other end, and a magnetic force of the permanent magnet that is excited. A trip coil that moves one end of the movable lever by the spring force of the cancellation reset spring, a drive circuit that detects a fault current and excites the trip coil, a limit switch that is turned on by the movement of one end of the movable lever, and the movable lever. And a display lever which is engaged with an orthogonal member to be rotated to open and close the display window, and which, when restored, is excited by a drive circuit to move the other end of the movable lever to restore one end thereof. Set may be a Blanc jar and Yoriru configuration.

Further, the display lever cooperates with an orthogonal member of the movable lever which engages in the vicinity of the second fulcrum around a second fulcrum which is substantially orthogonal to the movable fulcrum from the first fulcrum and is separated by a predetermined distance. The amount of movement of the end portion that opens and closes the display window is enlarged by the lever ratio.

Further, the display lever is provided on the lower side of the overhead bus bar, and is formed such that its length in the longitudinal direction is longer than the radial direction of the overhead bus bar.

The reset spring is so constructed that its spring force is weaker than the magnetic force of the permanent magnet.

The accident display is a light emission display or a radio wave emission display.

[0015]

According to the present invention, when there is a fault current, the drive circuit detects and makes a decision, and the trip coil is excited with direct current, and when the magnetic force of the permanent magnet is canceled, the pulling spring force of the reset spring is lost and the movable lever is moved to O. _The display lever is O ₂ point (second fulcrum) because it opens downward in the figure centered on ₁ point (first fulcrum)
One end moves to the left around the center, and the display window opens to allow the display of red and other colors. At this time, the limit switch is pushed by one end of the movable lever and becomes an ON condition. Next, when the cause of the accident point is removed and restored, the drive circuit is formed,
When the reset plunger is excited, the movable lever moves downward in the figure around the point O ₁ , the permanent magnet side moves upward, and the display lever is reset, so that the display window is closed again.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a diagram showing the correlation between the voltage V and the current I of the bus bar 1, and the abscissa shows four modes of T ₁ , Tx, Tr and T ₁ ′ as time transition state modes.

Generally, in the initial normal state, the mode is T ₁ mode, V = 6
It is 6 kV, I = 1000 A, and it is normally energized. Next, in the Tx mode, if an accident occurs on the bus bar, the current will increase to V = several 100V and I = 10000A, so for safety reasons, another device will operate continuously in a short period of 5 to 6 cycles to protect the circuit. Shut off.

In the Tr mode, since the bus 1 is stopped, V = 0 and I = 0 are set, and the accidental site is inspected after stopping for several hours.

In T ₁ mode, the accident site is found or removed and recharged, so V = 66 kV, I = 100
The current again flows to about 0 A and the normal operation is restored.

The above is a summary of all operating patterns of the bus in the substation. FIG. 2 is a cross-sectional view of a specific arrangement of the bus bar 1 in the substation premises. The busbar 1 is supported and branched by a suspension insulator 2 fixed to a steel structure.

The protection device detects the voltage with the voltage detector 5,
Current is detected by a current transformer (not shown) built in the circuit breaker 4, and the bus circuit is disconnected by the circuit breaker 4 when a fault current occurs. Here, the busbar accident on the outside of the premises is caused by the circuit breaker 4
〜Identified by the disconnector 3L side, and if there is an accident on the inside of the premises, the circuit breaker 4〜
The disconnectors 3X, 3Y, 1X, and 1Y are identified.

The overhead bus support type accident point locating device 6 of the present invention
Is installed at the X portion in FIG. 2 to locate and divide the multiple branch points of the busbar 1 inside the premises.

FIG. 3 is a view showing the construction of the overhead bus support type accident point locating device 6, which is supported on the bus bar 1 by a fixing metal fitting 7,
Two-piece current transformer 8 and display unit 9
Are fixed, and the two-part shield case 10 is screwed to the end surface of the fixing member 7. Therefore, it has a cylindrical shape in which the longitudinal side is larger than the radial side of the busbar 1.

FIGS. 4 and 5 show an example of the internal structure of the display unit 9, which is housed in the case 11 and the display window 20 is opened by opening and closing the display lever 17.

The closed loop magnetic path 12 has a U-shape and is interposed in the trip coil 15. The movable lever 14 rotates about an O ₁ point (first fulcrum), a thin permanent magnet 13 having an NS pole is fixed at one end, and a reset spring 16 is provided at the other end.
Is provided. When the trip coil 15 has no excitation force, one end of the movable lever 14 is attracted to the closed loop magnetic path 12 side by the permanent magnetic force of the permanent magnet 13, and the reset spring 16 is set weaker than the attraction force. One end of the orthogonal member is fixed near the O ₁ point of the movable lever 14,
The other end is rotatably engaged with the display lever 17.
One end of the display lever 17 on the O ₁ point side closes the display window 20, and the other end is rotatably supported at the O ₂ point (second fulcrum). Therefore, when the movable lever 14 rotates about the point O _1, the display lever 17 moves to the O position via the orthogonal member.
It rotates about _two points, and the display window 20 becomes visible. Since the stroke of the movable lever 14 is as small as 4 to 6 mm, the stroke of the display lever 17 on the display window 20 side is enlarged by the lever ratio at the O ₂ fulcrum.

If there is an accident current, the drive circuit 21 detects and determines that the trip coil 15 is excited with direct current, and if the magnetic force of the permanent magnet 13 is canceled, the tension of the reset spring 16 is lost and the movable lever 14 is lost. Is opened downward in the figure around the O ₁ point, one end of the display lever 17 is moved leftward around the O ₂ point, the display window 20 is opened, and a red display or the like is visible. At this time, the limit switch 18 is pushed by one end of the movable lever 14 and becomes an ON condition. Next, when the cause of the accident point is removed and the T ₁ ′ mode of recharging is entered, the drive circuit 21 makes a determination detection and a drive circuit is formed. When the reset plunger 19 is excited, the movable lever 14 moves around the O ₁ point. Since it moves downward in the figure, the permanent magnet 13 side strokes upward and the closed loop magnetic path 1 again.
2, and the display lever 17 is reset, so that the display window 20 is closed again.

FIG. 6 shows an electric circuit in the display unit 9. The output of the current transformer 8 is taken into a drive circuit 21 and divided into two rectifying circuits 22. One is supplied to the DC power supply of the coil power supply for driving, and the other is supplied to the first and second threshold circuits 24 via the constant voltage circuit 23 and the volume. The first and first threshold circuits 24 turn on the trip coil (T) 15 and the reset plunger (R) 19.
The transistor 25 is provided to individually set the threshold current of the current transformer 8, and each transistor 25 has an ON condition. Therefore, the drive circuit 21 is molded so that only the knob for enhancing the environment resistance and externally adjusting the volume is exposed. As shown in FIG. 7, the condition of the limit switch 18 is that the trip coil T operates in the Tx mode to cause the movable lever 14 to move.
When the stroke is, the condition is OFF → ON, and when the mode is the T ₁ ′ mode, the reset plunger R operates and when the movable lever 14 has the reset stroke, the condition is ON → OFF. The limit switch 18 is provided to prevent simultaneous operation because the input of the drive circuit 21 is the primary current input from the current transformer 8 and the current operation threshold value of R and T is R <T condition. It has been resolved.

That is, in the T ₁ mode, the input of the current transformer 8 is given to the drive circuit 21, but the limit switch 1
Since 8 is OFF, the reset plunger R does not operate. In the Tx mode, when the threshold value is unconditionally exceeded, the transistor 25 is turned on, so that the trip coil T is excited and the movable lever 14 is opened. As a result, limit switch 1
8 is an ON condition. In Tr mode, nothing happens because there is no input to the current transformer 8.

In the T ₁ 'mode, when the threshold circuit 24 is turned on by the input of the current transformer 8, the transistor 25 is turned on and the limit switch 18 is turned on, so that the reset plunger R is driven and the movable lever 14 is closed.

Therefore, the T ₁ and T ₁ ′ modes are the same in terms of the primary current, but can be discriminated by the limit switch 18.

The limit switch 18 is turned ON / OF.
When F is fast, the ON condition is made variable by the delay circuit of the reset plunger R side delay circuit 24 so that hunting can be prevented.

Although one example of the installation in the substation premises has been described above, this example also has the same purpose of installing the distribution line at a multi-branch point outside the 20 kV system and at the branch point of the transmission tower. Is effective.

According to the present invention, the following effects can be obtained.

(1) Since it is mounted on an overhead bus, it does not require ground insulation (generally, a supporting insulator is required in the case of a high voltage of 66 kV), and the cost is low.

(2) Since the busbar length side is equal to or larger than the busbar diameter side and the whole is covered by the shield case, the external dimensions are reduced (in this embodiment, the busbar side 1
(00 × 100 mm, busbar length side 200 mm) and no corona discharge, so there is no radio interference in the surrounding area.

(3) Since the current transformer and the shield case are divided into two parts, they can be installed anywhere on the existing busbar, and
With respect to the display of the display unit, the presence / absence of an accident can be easily monitored only by visually observing the ON / OFF state from the display window.

(4) Since the display unit is mainly composed of a mechanical system and the movable lever is rotated by the permanent magnet force, no malfunction occurs.

(5) The method is changed only in the display unit, and in addition to the mechanical display, the sound display, the light emission display, the radio wave emission display, etc. can be selected according to the atmosphere and environmental conditions of the installation place, so that the versatility is improved. It becomes possible to provide a small and lightweight accident point locator.

[0040]

According to the present invention, since the current transformer and the display unit are supported at a plurality of positions on the overhead bus, it is possible to easily monitor the presence or absence of an accident at that position due to a fault current. Moreover, since the accident indication is caused by the rotation of the movable lever, there is no malfunction. In addition, since light emission display, radio wave emission display, etc. can be selected according to the atmosphere and environmental conditions of the installation location, it is possible to provide a general-purpose compact and lightweight overhead bus support type accident point locator.

[Brief description of drawings]

[Fig. 1] Energization in voltage / current correlation of overhead bus,
It is a figure explaining the mode of an accident, suspension, and re-energization.

FIG. 2 is a diagram illustrating a mounting position of an embodiment of the present invention with respect to a bus bar arrangement in a substation premises.

FIG. 3 is an external view showing an embodiment of the present invention.

FIG. 4 is a plan view showing an internal configuration of the display unit of FIG.

5 is a side view showing an internal configuration of the display unit of FIG.

6 is an electric circuit diagram of the display unit of FIG.

FIG. 7 is a diagram illustrating a relationship between operating components inside the display unit of FIG. 6 and a bus bar mode.

[Explanation of symbols]

 6 Aerial bus support type accident point locator 8 Current transformer 9 Display unit 10 Shield case 13 Permanent magnet 14 Movable lever 15 Trip coil 18 Limit switch 19 Reset plunger 20 Display window

Claims (6)

[Claims] 1. A current transformer that is supported by an overhead bus through a fixing member to detect an alternating current, and a fault current that flows adjacent to the current transformer and flows through the overhead bus. A display unit for resetting an accident display is provided, and the display unit is normally connected to a rectifier circuit for converting into a direct current, a constant voltage circuit connected to the rectifier circuit, and a secondary side of the constant voltage circuit. A first threshold circuit and a second threshold circuit for identifying a current or a fault current, and a plunger coil connected between the first threshold circuit and the second threshold circuit and the rectifier circuit , A limit switch and a trip coil for controlling the opening / closing operation of the limit switch. 2. A current transformer supported by an overhead bus through a fixing metal fitting to detect an alternating current, and a fault current adjacent to the current transformer flowing in the overhead bus, the fault current is detected, and the fault is displayed to recover the fault. A display unit for resetting an accident display is provided, and the display unit has a movable lever fixed to one end and a reset spring connected to the other end to rotate about a first fulcrum, and by excitation. A trip coil that cancels the magnetic force of the permanent magnet and moves one end of the movable lever by the spring force of the reset spring, a drive circuit that detects the accident current and excites the trip coil, and a trip coil Limit switch that is turned on by movement,
A display lever that engages with the orthogonal member of the movable lever and is rotated to open and close a display window, and a reset blanker that is excited by the drive circuit at the time of restoration and moves the other end of the movable lever to restore one end thereof. An aerial bus support type accident point locator characterized by the following. 3. The display lever is an orthogonal member of the movable lever, which engages in the vicinity of the second fulcrum about a second fulcrum which is substantially orthogonal to the movable fulcrum and is separated by a predetermined distance from the first fulcrum. The overhead bus support type accident point locating device according to claim 2, wherein the amount of movement of the end portion that opens and closes the display window in cooperation with each other is enlarged by a lever ratio. 4. The aerial bus bar support type according to claim 2, wherein the display lever is provided below the aerial bus bar and has a longitudinal length longer than a radial direction of the aerial bus bar. Accident location device. 5. The overhead bus support type accident point locating device according to claim 2, wherein the reset spring is formed so that the spring force is weaker than the magnetic force of the permanent magnet. 6. The overhead bus support type accident point locating device according to claim 1, wherein the accident display is a light emission display or a radio wave emission display.