JPH0561594B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) This invention relates to a fault current detection and display device attached to a power distribution line.

(Prior art) At present, methods for detecting and displaying ground faults and short circuit faults in overhead power distribution lines include a target method in which a display object is protruded from the detection part when a fault is detected, and a magnetic display device is excited when a fault is detected, and its magnetic force A system that rotates the display board of a magnetic display device to indicate a fault; an oil damper system that pulls up the display board in oil when a fault is detected and then lowers the display board with a delay;
Or visible light that emits visible light when a failure is detected.
LED methods etc. have been proposed.

(Problem to be Solved by the Invention) However, the visible distance of these conventional display devices is short, and it is difficult to see whether the display is operating or not unless you go close to where the display device is installed. There were cases where it was not possible to distinguish. Particularly with the visible light LED system, there was a problem that it was difficult to distinguish during the daytime due to the bright surroundings.

The present invention solves the above-mentioned problems and provides a fault detection display device for power distribution lines that allows fault display to be confirmed from a distance and does not change the surrounding landscape because it is not easily visible to third parties. It is an object.

Structure of the Invention (Means for Solving Problems) The fault detection display device of this invention detects ground faults in distribution lines,
a failure detection circuit that detects a short-circuit failure; an infrared light emission drive circuit that operates based on detection by the detection circuit;
The gist thereof is to include an infrared light emitting element driven to emit infrared light by the infrared light emission drive circuit.

(Function) With the above configuration, when the failure detection circuit detects a short circuit or a ground fault in the distribution line, the infrared light emission drive circuit causes the infrared light emitting element to emit infrared light based on the detection operation of the failure detection circuit.

(Example) Hereinafter, an example embodying the present invention will be described with reference to FIGS. 1 and 2.

The failure detection display device 1 is attached to a utility pole 2, and a display section 3 is provided on one side of the failure detection display device 1.

The electrical configuration of the fault detection display device 1 will be explained with reference to FIG. ), and a known ground fault detector (not shown) that detects zero-sequence current and zero-sequence voltage, such as ZCT and ZPD, which are also provided on the distribution line. When the overcurrent detector detects an overcurrent flowing through the distribution line during a short circuit failure, the overcurrent detector outputs a detection signal to the short circuit/ground fault detection circuit 10.

Then, the short circuit/ground fault detection circuit 10 operates based on the detection signal from the overcurrent detector, and causes the next stage timer circuit 11 to operate as a timer for a predetermined period of time. Furthermore, when the ground fault detector detects zero-sequence current and zero-sequence voltage flowing through the distribution line during a ground fault, the ground fault detector transmits these detection signals to the short circuit/ground fault detection circuit 10.
Output to. Then, the short circuit/ground fault detection circuit 10 operates based on the detection signal from each fault detector,
The timer circuit 11 at the next stage is operated for a predetermined time. When the timer circuit 11 operates, it applies a control signal to the infrared light emitting drive circuit 12 at the next stage for a certain period of time until the timer expires.

The infrared light emission drive circuit 12 is composed of a modulation circuit 13 and an infrared light emission circuit 14, and the modulation circuit 13 includes a switching transistor 15, a transistor 16,
and an oscillation circuit 17. The switching transistor 15 turns on when the control signal is applied, and turns off when the control signal is removed. The transistor 16 is connected to the collector of the switching transistor 15 via a resistor 18, and turns on when the potential at point A drops, that is, when the switching transistor 15 turns on. Note that when the switching transistor 15 is off, the potential of A increases and the transistor 16 turns off.

The oscillation circuit 17 consists of gates 21 to 24.
It is configured with a NAND gate configuration, and when the transistor 16 turns on, a signal is input,
The signal is modulated to 50 Hz by gates 21 and 22 and 38 kHz by gates 23 and 24, and the modulated signal is output to the infrared light emitting circuit 14 as a drive signal. In addition, 25
is a resistor connected between the output terminal of gate 21 and the input terminal, 26 is a resistor connected between the output terminal of gate 22 and gate 2
1, a capacitor connected between the input terminals of gate 23, 27 an output terminal of gate 23, a resistor connected between the input terminals, and 28 an output terminal of gate 24 and gate 23.
is a capacitor connected between the input terminals of

The infrared light emitting circuit 14 includes infrared light emitting diodes 30 and 31 as infrared light emitting elements, and transistors 32 to 32.
35 etc., both infrared light emitting diodes 3
0 and 31 are arranged on the display section 3. and,
When a drive signal is input from the modulation circuit 13,
The signal is current-amplified by transistors 32 and 33, and the infrared light emitting diode 30 transmits the 38kHz signal in infrared light at a unique peak wavelength.
It emits light (in this example, it emits infrared light with a wavelength of 940 nm). The infrared light emitting diode 33 also emits light (in this embodiment, it emits infrared light with a wavelength of 940 nm) in order to transmit the 38 kHz signal current amplified by the transistors 34 and 35 using infrared light with a unique peak wavelength. do. Note that 36 is a transistor Tr.
A resistor is connected to the base of 32 and the output terminal of the modulation circuit 13, and 37 and 38 are transistors 3 and 38, respectively.
resistor connected to the collector of 2,34, 39,4
0 is a resistor connected to the emitters of transistors 33 and 35.

When the short circuit/ground fault detection circuit 10 operates to detect a short circuit or a ground fault as described above, the infrared light emitting drive circuit 12 is driven for a predetermined period of time until the timer circuit 11 times up, and the infrared light emitting diode 3 is activated.
0,31 thereby emits infrared light. While emitting infrared light for a predetermined period of time, a supervisor uses a known infrared image converter 41 to monitor the display section 3 of the failure detection display device 1 from a distance. Since the infrared image converter 41 converts the infrared light of the infrared light emitting diodes 30 and 31 in the display section 3 into visible light for the supervisor to see, the supervisor can see that the failure detection display device 1 is displaying a failure. can be confirmed.

Note that the present invention is not limited to the above-mentioned embodiments, and can be arbitrarily modified without departing from the spirit of the present invention.

Effects of the Invention As detailed above, this invention emits infrared light, which has a higher quantum efficiency than visible light, when a failure is indicated. The light emitting state of the element can be visually confirmed. Furthermore, since infrared light, which is rare in nature, is used, detection reliability can be improved. Furthermore, since infrared light cannot be seen without the use of special monitoring equipment, it cannot be identified by third parties other than those involved, and the infrared light does not change the surrounding scenery. It has a great effect.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram of a fault current detection device according to an embodiment of the present invention, and FIG. 2 is a schematic diagram of the fault current detection and display device attached to a utility pole. 1... Failure detection display device, 3... Display section, 10
...Short circuit ground fault detection circuit, 11...Timer circuit,
12... Infrared light emission drive circuit, 13... Modulation circuit,
14... Infrared light emitting circuit, 30, 31... Infrared light emitting diode.

Claims (1)

[Scope of Claims] 1. A failure detection circuit that detects a ground fault or short circuit failure in a distribution line; an infrared light emission drive circuit that operates based on detection by the detection circuit; and an infrared light emission drive circuit that operates based on detection by the detection circuit; A fault detection display device for a power distribution line, including a driven infrared light emitting element.