JP2007335794A - Deterioration detector for protection element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a deterioration detector for a protection element which detects deterioration of the protection element precisely even at a remote place by a simple constitution. <P>SOLUTION: The deterioration detector 100 for the protection element is provided with a state detection unit 10, a transmitter 20, a signal processor 30, a warning output part 40, and optical cables 50 and 60. The detector detects deterioration of a gapless arrester 200 at the remote place. The state detection unit 10 is provided with a temperature sensor, a thermal conductor which is arranged interposed between the temperature sensor and the gapless arrester 200 to improve thermal conductivity, and a heat insulator which covers the temperature sensor to reduce heat conduction from external environment. The state detection unit 10 conducts temperature conducted from the gapless arrester 200 preferentially to the temperature sensor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a protection element deterioration detection device that detects deterioration of a lightning protection element with a simple configuration.

The power supply circuit security device has a function of protecting various devices connected to the low voltage side by preventing an overcurrent / overvoltage caused by a lightning surge entering from the distribution line from flowing to the low voltage side. For this reason, the power supply circuit security device includes a protective element such as a gapless lightning arrester or a varistor for absorbing energy due to lightning surge overcurrent and overvoltage.
Now, the overcurrent and overvoltage of lightning surge are repeatedly applied to these protection elements, so that the protection function deteriorates over time, the leakage current flowing through the protection element ground wire increases, and the amount of heat generation increases. It is known that it will eventually lead to destruction. Therefore, it is necessary to take measures against such deterioration over time.

  For example, Patent Document 1 (Title of Invention: Zinc Oxide Type Lightning Arrester Preventing Method and Zinc Oxide Type Lightning Arrester with Thermal Runaway Prevention Function) describes conventional techniques for countermeasures against deterioration of such protective elements. In the technology, an invention is disclosed in which an electric current is interrupted and heat generation is stopped by generating a discharge interval (gap) using abnormal heat generation of a zinc oxide type lightning arrester.

Japanese Unexamined Patent Publication No. 2003-203803 (paragraph number 0023, FIG. 2)

In the above-described conventional technology, the destruction of the protective element (final form of deterioration) is detected only after the deterioration has progressed over a long period of time and finally the abnormal heat generation has occurred.
However, it is sufficient that measures can be taken immediately when such destruction of the protective element occurs, but there are cases where measures cannot be taken.

For example, when there is a lightning strike, it was common for security personnel to go directly to the installation site of the power supply circuit security device and take necessary measures. However, it is sufficient if the power circuit security device is installed in a place where it can be confirmed directly, but for example, if a power circuit security device is installed at an unmanned summit relay station, climbing is possible in winter. In some cases, the countermeasures such as damage to the protective element could not be resolved immediately, such as delaying countermeasures for a long time.
So, if there is a power circuit security device in a remote area such as an unmanned summit relay station, there is a situation where the security staff wants to check the deterioration of the protective element directly before the arrival of the winter, and perform maintenance. There are many such facilities located in remote locations, and it is very rare that damage to the protective elements is found at the time of confirmation, so that the deterioration of the protective elements of the power circuit security device can always be confirmed remotely. In the meantime, there was a request to perform the minimum necessary efficient maintenance.

  Accordingly, the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a simple configuration that can detect deterioration of a protection element with high accuracy even in a remote place. An object of the present invention is to provide a device deterioration detection device.

A deterioration detection device for a protective element according to claim 1 of the present invention includes:
A protection element deterioration detection device that detects deterioration of a protection element that protects a device from invading overvoltage,
A state detection unit that is arranged outside the protection element and outputs a state signal indicating the state of the protection element;
A transmission device that modulates and outputs a state signal from the state detection unit to a transmission signal;
A signal processing unit that demodulates the transmission signal and acquires state data to detect deterioration of the protection element, generates an alarm signal for notifying the deterioration of the protection element, and outputs the alarm signal;
An alarm output unit for inputting an alarm signal from the signal processing unit and outputting an alarm; and
Is provided.

Moreover, the deterioration detection device for a protective element according to claim 2 of the present invention includes:
In the deterioration detection apparatus for protective elements according to claim 1,
The temperature of the protective element is detected as the state, and the temperature signal of the protective element is used as the state signal.
The state detection unit is
A temperature sensor;
A thermal conduction part disposed between the temperature sensor and the protection element to improve thermal conductivity;
An insulation that covers the temperature sensor and reduces heat conduction from the external environment;
And conducting to the temperature sensor in preference to the temperature conducted from the protective element.

Moreover, the deterioration detector for protective elements according to claim 3 of the present invention is
In the protection element deterioration detection device according to claim 1 or 2,
Detecting mechanical strain of the protective element as the state, and using a detection signal due to movement of the mechanical strain of the protective element as the state signal,
The state detection unit is
A detector for detecting mechanical strain of the protective element;
A switch that outputs a detection signal when the detection body is displaced by a predetermined amount;
It is characterized by providing.

  According to the present invention as described above, it is possible to provide a deterioration detection device for a protection element that has a simple configuration and detects the deterioration of the protection element with high accuracy even in a remote place.

The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a protection element deterioration detection apparatus according to this embodiment.
As shown in FIG. 1, the protection element deterioration detection device 100 includes a state detection unit 10, a transmission device 20, a signal processing unit 30, an alarm output unit 40, and optical cables 50 and 60. The protection element deterioration detection device 100 detects deterioration of a gapless lightning arrester 200 which is a specific example of a protection element. In addition, the state detection means temperature detection in this embodiment. The overall configuration looks like this.

Next, each part will be described with reference to the drawings. 2A and 2B are explanatory views of the state of the state detection unit 10 attached to the gapless lightning arrester 200, in which FIG. 2A is a front view and FIG. 2B is a bottom view. FIG. 3 is an enlarged cross-sectional view of the state detection unit 10.
The state detection unit 10 is disposed outside the gapless lightning arrester 200 and in contact with the surface thereof, detects the temperature of the gapless lightning arrester 200, and outputs a temperature signal to the transmission device 20.

As shown in FIG. 3, the state detection unit 10 includes a temperature sensor 10a, a heat conducting unit 10b, and a heat insulating unit 10c. The temperature sensor 10a has a temperature measurement function and outputs a temperature signal. The heat conducting unit 10b is disposed between the temperature sensor 10a and the gapless lightning arrester 200. The heat conducting portion 10b is made of a material having a high heat conductivity, further increases the degree of adhesion and increases the contact area, and has a function of improving the heat conductivity.
The heat insulating part 10c covers the outer surface other than the contact surface of the heat conducting part 10b to the temperature sensor 10a, so that heat from the external environment is not transmitted.
In this embodiment, as shown in FIGS. 2A and 2B, the state detection unit 10 is held and fixed to the lower side of the gapless lightning arrester 200 by a mounting plate 10d.
By adopting such a structure, the influence of the temperature of the external environment can be reduced, and heat conducted from the gapless lightning arrester 200 can be preferentially conducted to the temperature sensor 10a.

  Returning to FIG. 1, the transmission device 20 converts the temperature signal from the state detection unit 10 into a transmission signal and outputs it. Here, an optical cable 50 capable of long-distance transmission is used. The optical cable 50 transmits this transmission signal to the signal processing unit 30. For example, the optical cable 50 may be configured to protect the transmission signal from induced lightning using, for example, an existing OPGW on a steel tower. Various transmission methods can be adopted for this transmission signal according to the transmission form such as a digital signal and an analog signal.

  4A and 4B are external views of the signal processing unit 30, in which FIG. 4A is a side view and FIG. 4B is a front view. The signal processing unit 30 demodulates the transmission signal transmitted via the optical cable 50 and acquires temperature data. Then, when the temperature data exceeds predetermined temperature data, it is detected that the gapless lightning arrester 200 has deteriorated. For example, in the gapless lightning arrester 200, as the zinc oxide element (ZnO), which is an insulation resistance, deteriorates, the leakage current flowing through the ground line also increases, so the heat generation temperature increases. For this reason, deterioration progresses as the temperature data increases, and it can be determined that maintenance replacement is necessary when the set temperature data that is the limit point is exceeded. The signal processing unit 30 that has made such a determination causes the LED display unit 31 assigned to each gapless lightning arrester 200 to blink to notify the abnormality. This blinking can be stopped by pressing the reset button 32. Furthermore, the signal processing unit 30 generates an alarm signal for notifying the deterioration of the gapless lightning arrester 200 and outputs this alarm signal. The optical cable 60 transmits this alarm signal to the alarm output unit 40. Such a signal processing unit 30 can connect a total of six optical cables 50, and can detect the deterioration of the six gapless lightning arresters 200.

  5A and 5B are external views of the alarm output unit 40. FIG. 5A is a rear view, FIG. 5B is a side view, and FIG. 5C is a front view. The alarm output unit 40 inputs an alarm signal from the signal processing unit 30 and outputs an alarm. As shown in FIG. 1, the alarm output unit 40 is connected to an alarm output line 70, a power supply line 80, and a ground line 90. The alarm output unit 40 includes a power switch 41, a power lamp 42, a reset switch 43, an alarm lamp 44, a fuse 45, an optical cable input terminal 46, an alarm terminal 47, a power supply terminal 48, and an FG terminal 49. In this embodiment, the alarm is output by blinking the alarm lamp 44. Although not shown, a visual / auditory alarm may be output to a security worker at a remote place by a display unit / speaker or the like connected via the alarm terminal 47.

The protection element deterioration detection device 100 of this embodiment is as described above.
Note that the gapless lightning arrester 200 has been described as a specific example of the protective element. However, the present invention is not limited to the gapless lightning arrester 200 and may include an existing lightning arrester such as a gap lightning arrester and a varistor.

  Moreover, you may improve further the deterioration detection apparatus 100 for protective elements demonstrated previously. For example, considering that the temperature measured by the state detection unit 10 is affected by the external environment, a new temperature sensor for measuring the external environment temperature (see FIG. 5) at the location where the gapless lightning arrester 200 and the state detection unit 10 are installed. (Not shown), the external environment temperature according to the installation environment of the gapless lightning arrester 200 is measured and output as environmental temperature data, and the signal processing unit 30 detects the deterioration of the gapless lightning arrester 200 in consideration of the temperature data and the environmental temperature data. You may do it. As this deterioration detection method, calibration temperature data which is a difference value between temperature data and environmental temperature data may be used to compare the calibration temperature data with the set temperature data. In this way, even if the surface temperature of the gapless lightning arrester 200 is affected by the external environment, such as in summer and winter, the temperature of the external environment can be canceled to approach the pure heat generation temperature. .

Further, as another method of calibration, the actual heat generation temperature of the gapless lightning arrester 200 corresponding to the external environment temperature and the surface temperature of the gapless lightning arrester 200 is obtained in advance by experiments or the like and stored in a memory (not shown) of the signal processing unit 30. Determining the actual exothermic temperature corresponding to these temperatures when measuring the external environment temperature and the surface temperature, and detecting deterioration when the set temperature exceeds the set temperature by paying attention to the temporal change of the actual exothermic temperature. Anyway.
The protection element deterioration detection device 100 may employ such a configuration.

Next, further improvements will be described with reference to the drawings. FIG. 6 is an explanatory view of the state of the state detection unit attached to the gapless lightning arrester, and FIG. 7 is an assembly view of the state detection unit to the gapless lightning arrester.
As shown in FIG. 6, the improved state detection unit 11 is attached to the gapless lightning arrester 200. As shown in FIG. 7, the state detection unit 11 includes a base 11a, a nut plate 11b, a cantilever 11c (which is a specific example of the detection body of the present invention), a switch 11d, a heat conducting unit 11e, a temperature sensor 11f, and a heat insulating unit. 11g and a holder 11h are provided.

  The base 11a and the nut plate 11b are attached so as to sandwich the protruding portion 201 of the gapless lightning arrester 200. Then, a strain detection unit including a cantilever 11c and a switch 11d that outputs a binary detection signal of ON / OFF is attached to the base 11a. Further, a temperature detection unit including a heat conducting unit 11e, a temperature sensor 11f, a heat insulating unit 11g, and a holder 11h is also attached.

  Although mechanical strain is detected by the strain detection unit, when a surge current flows through the gapless lightning arrester 200, the bottom of the gapless lightning arrester 200 is deformed so that the center swells. At this time, the cantilever 11c moves, for example, to the outside, and the detector in the OFF state of the switch 11d is moved to turn the detector on. As a result, the switch 11d outputs a detection signal. Thereafter, as shown in FIG. 1, the transmission device 20 modulates the detection signal from the distortion detection unit of the state detection unit 11 into a transmission signal and outputs the transmission signal. A transmission signal from the transmission device 20 is input to the signal processing unit 30 via the optical cables 50 and 60.

  The signal processing unit 30 demodulates the transmission signal, acquires state data to detect deterioration of the protection element, generates an alarm signal for notifying deterioration of the gapless lightning arrester 200, and outputs this alarm signal. The alarm output unit 40 inputs an alarm signal from the signal processing unit 30 and outputs an alarm.

In addition, about the temperature detection unit, the temperature sensor, the heat conduction unit, and the heat insulation unit have the same names although the symbols are different, and those with the same name are duplicated as having the same configuration and function. Is omitted. Since such a temperature detection unit performs the function described above, it can detect an abnormality due to heat generation.
As described above, according to the present embodiment, since mechanical strain is detected in addition to temperature, deterioration of the gapless lightning arrester 200 can be reliably detected.

It is a block diagram of the deterioration detection apparatus for protection elements of the best form for implementing this invention. It is explanatory drawing of the attachment state of the state detection unit to a gapless lightning arrester, Comprising: Fig.2 (a) is a front view, FIG.2 (b) is a bottom view. It is an expanded sectional view of a state detection unit. FIG. 4A is an external view of a signal processing unit, FIG. 4A is a side view, and FIG. 4B is a front view. FIG. 5A is an external view of an alarm output unit, FIG. 5A is a rear view, FIG. 5B is a side view, and FIG. 5C is a front view. It is explanatory drawing of the attachment state of the state detection unit to a gapless lightning arrester. It is an assembly drawing of the state detection unit to a gapless lightning arrester.

Explanation of symbols

100: Deterioration detection device 10 for protection element 10: State detection unit 10a: Temperature sensor 10b: Heat conduction part 10c: Heat insulation part 10d: Mounting plate 11: State detection unit 11a: Base 11b: Nut plate 11c: Cantilever 11d: Switch 11e: Thermal conduction unit 11f: Temperature sensor 11g: Thermal insulation unit 11h: Holder 20: Transmitter 30: Signal processing unit 31: LED display unit 32: Reset button 40: Alarm output unit 41: Power switch 42: Power lamp 43: Reset switch 44 : Alarm lamp 45: Fuse 46: Optical cable input terminal 47: Alarm terminal 48: Power supply terminal 49: FG terminal 50: Optical cable 60: Optical cable 70: Alarm output line 80: Power supply line 90: Ground line 200: Gapless lightning arrester

Claims (3)

A protection element deterioration detection device that detects deterioration of a protection element that protects a device from invading overvoltage,
A state detection unit that is arranged outside the protection element and outputs a state signal indicating the state of the protection element;
A transmission device that modulates and outputs a state signal from the state detection unit to a transmission signal;
A signal processing unit that demodulates the transmission signal and acquires state data to detect deterioration of the protection element, generates an alarm signal for notifying the deterioration of the protection element, and outputs the alarm signal;
An alarm output unit that outputs an alarm by inputting an alarm signal from the signal processing unit; and
A deterioration detecting device for a protective element comprising: In the deterioration detection apparatus for protective elements according to claim 1,
The temperature of the protective element is detected as the state, and the temperature signal of the protective element is used as the state signal.
The state detection unit is
A temperature sensor;
A thermal conduction part disposed between the temperature sensor and the protection element to improve thermal conductivity;
An insulation that covers the temperature sensor and reduces heat conduction from the external environment;
A deterioration detecting device for a protective element, characterized in that the temperature conducted from the protective element is prioritized and conducted to the temperature sensor. In the protection element deterioration detection device according to claim 1 or 2,
Detecting mechanical strain of the protective element as the state, and using a detection signal due to movement of the mechanical strain of the protective element as the state signal,
The state detection unit is
A detector for detecting mechanical strain of the protective element;
A switch that outputs a detection signal when the detection body is displaced by a predetermined amount;
A deterioration detecting device for a protective element, comprising:

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