JPH0125206B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a deterioration detection device for a gear press arrester, and more particularly to a deterioration detection device for a gear press arrester, which is capable of automatically detecting deterioration in its field and thereby simplifies maintenance.

[Technical Background of the Invention] In recent years, in electrical stations such as substations, in order to protect the equipment installed there from surge-like abnormal voltages such as lightning or transient overvoltages during switching,
Gear press lightning arresters are often used.

FIG. 1 shows a configuration example of a conventional gear press arrester. In Fig. 1, a lightning arrester has a resistor column 1 made of a plurality of stacked ZnO nonlinear resistors with good nonlinearity, housed in an insulating container 2 such as an insulator, and its high voltage side terminal connected to a power transmission line 3. In addition, the ground side terminal is grounded via a resistor 4. Further, a disconnector 5 is provided in parallel with the resistor 4.

Maintenance diagnosis for deterioration of such a gear press lightning arrester is performed as follows. That is, the current flowing through the resistor column 1 is roughly divided into a capacitive current and a resistive current, but as shown in the figure, the capacitive current is canceled by a differential amplifier 8 using capacitors 6 and 7, and its output is A certain resistance current 9
The presence or absence of deterioration can be determined by measuring the size of . In addition, in the figure, 10 is a protective gap provided in parallel with the resistor 4.

[Problems with Background Art] However, such conventional deterioration detection has the following problems. That is, the first
is the inability to automatically detect deterioration. In other words, since the deterioration detection described above is a method that normally operates with the disconnector 5 closed, it is opened during maintenance and inspection and the current flowing through the resistor 4 is measured, so the frequency of maintenance and inspection is not appropriate. However, it is almost impossible to maintain and inspect a large number of lightning arresters at appropriate intervals.

Second, it is often technically extremely difficult to accurately measure the magnitude (peak value) of the resistance component current. In other words, since the resistive current is small compared to the capacitive current, the resistive current fluctuates depending on the capacitive current elimination method, the presence of leakage current other than resistor column 1, distortion of the grid voltage, etc. It is difficult to measure the resistance component current.

[Purpose of the Invention] The present invention has been made to solve the above-mentioned problems, and the purpose is to automatically detect the presence or absence of deterioration of the lightning arrester and to omit maintenance. An object of the present invention is to provide a simple deterioration detection device for a lightning arrester.

[Summary of the Invention] In order to achieve the above object, a deterioration detection device for a lightning arrester according to the present invention provides a gear press lightning arrester configured by housing a resistor column formed by stacking a predetermined number of non-linear resistors in an insulating container. In response to the temperature rise of the resistor for detecting leakage current, the resistor for detecting leakage current installed on the ground side of the gear press arrester, the protective gap installed in parallel with the resistor for detecting leakage current, and the resistor for detecting leakage current. , and thermal response means for detecting that the temperature has exceeded a predetermined value and outputting a deterioration detection signal.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described as shown in the drawings.

FIG. 2 shows an example of the configuration of a deterioration detection device for a lightning arrester according to the present invention. The same parts as those in FIG. That is, in this embodiment, a resistor 11 for detecting leakage current is provided on the ground side of a gear press arrester in which a resistor column 1 is housed in an insulating container 2.
As shown in the figure, a low melting point metal 14 which melts at a temperature higher than a predetermined value is sandwiched between two metal pieces 12 and 13 as a thermally responsive element that responds to the temperature rise near the top of 1. Furthermore, the relay contacts 15 are short-circuited by the melting of the low melting point metal 14, and a deterioration detection signal is output from the contact terminals 16. Here, 12 to 16 constitute a thermal response means, which is housed in a container 17 together with the resistor 11. Furthermore, the deterioration detection signal is transmitted from the contact terminal 16 to a location such as a substation board room by a transmission means (not shown) so that an alarm can be displayed. Note that as the low melting point metal 14, a metal such as solder having a melting point in the range of 50 to 200° C. is used.

In the deterioration detection device configured as described above, the resistance current flowing through the resistor column 1 is small when there is no deterioration in the lightning arrester. Therefore, the temperature rise of the resistor 11 and the metal piece 12 with respect to this current is small, and the low melting point metal 14 does not melt. In addition, even if the arrester is activated due to large lightning or a switching surge and the resistor column 1 generates heat, the protective gap 10 will be closed due to the IR drop of the resistor 11 for detecting leakage current.
Since the surge arrester is designed to discharge, there is no possibility that the operation of the lightning arrester will be mistakenly detected as deterioration.

On the other hand, when the lightning arrester deteriorates and the resistance current of the resistor column 1 increases and exceeds the reference value, the temperature of the resistor column 1 and the resistor 11 for detecting leakage current increases.
The temperature of the metal piece 12 also rises. As a result, when the temperature of the low melting point metal 14 rises and becomes higher than its melting point temperature, the low melting point metal 14 melts and the metal piece 13
falls and is short-circuited with relay contact 15. The resulting deterioration detection signal is transmitted from the contact terminal 16 to a location such as a substation room through a transmission means (not shown), and an alarm is displayed to automatically detect the presence of deterioration.

As described above, in this embodiment, in a gear press arrester configured by housing a resistor column 1 formed by stacking a predetermined number of ZnO nonlinear resistors in an insulating container 2, In response to the temperature rise of the resistor 11 for detecting leakage current, the protective gap 10 provided in parallel with the resistor 11 for detecting leakage current, and the resistor 11 for detecting leakage current, the temperature rises to a predetermined value. A deterioration detecting device is constituted by a thermally responsive means that detects the occurrence of the above and outputs a deterioration detection signal.

Therefore, since deterioration of the lightning arrester can be automatically detected, there is no need to perform maintenance until a warning to that effect is issued. Further, for the above-mentioned reasons, it is no longer necessary to maintain the lightning arresters at appropriate intervals as in the past, so maintenance can be simplified and a large number of lightning arresters can be maintained extremely easily.
Furthermore, since the device is constructed from only the metal pieces 12, 13, relay contacts 15, etc. as described above, the construction is extremely simple and excellent in reliability and economy.

Note that the present invention is not limited to the above embodiments.

(1) In the above embodiment, the metal pieces 12, 13 and the low melting point metal 14 were attached near the top of the resistor 11 for leakage current detection, but they are attached near the bottom of the resistor 11 as shown in FIG. In this case, no high voltage is applied to the contact terminal 16, so deterioration can be detected more safely.

(2) As a thermally responsive element, instead of the metal pieces 12, 13 and the low melting point metal 14, a thermostat 18 is provided near the resistor 11 as shown in FIG. 4, and its operation short-circuits the relay contacts 16. Alternatively, the deterioration detection signal may be output.

(3) As shown in Fig. 5, a resistor 19 is provided in series with the resistor 11 for detecting leakage current shown in Fig. 2 above, and when the arrester deteriorates and a deterioration detection signal is output, the disconnection occurs. Open the container 20 and remove the resistor 19.
By taking out the current flowing through the contact terminal 21 and measuring it, it is possible to quantitatively understand the deterioration status of the lightning arrester.

[Effects of the Invention] As explained above, according to the present invention, the presence or absence of deterioration of the lightning arrester can be automatically detected and maintenance can be omitted, and the deterioration of the lightning arrester is extremely reliable with a simple configuration. A detection device can be provided.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a conventional lightning arrester deterioration detection device, FIG. 2 is a block diagram showing an embodiment of the present invention,
FIGS. 3 to 5 are block diagrams showing other embodiments of the present invention. DESCRIPTION OF SYMBOLS 1... Resistor column, 2... Insulating container, 3... Power transmission line, 4, 19... Resistor, 11... Resistor for detecting leakage current, 5, 20... Disconnector, 6, 7... …
Capacitor, 8... Differential amplifier, 9... Resistance current, 10... Protective gap, 12, 13... Metal piece, 14... Low melting point metal, 15... Relay contact,
16, 21...Contact terminal, 17...Container, 18...
...Thermostat.

Claims (1)

[Scope of Claims] 1. A gear press lightning arrester configured by housing a resistor column formed by stacking a predetermined number of non-linear resistors in an insulating container, comprising: a leakage current detection device provided on the grounding side of the gear press arrester; a protective gap provided in parallel with the resistor for detecting leakage current, and detecting that the temperature has exceeded a predetermined value in response to a temperature rise of the resistor for detecting leakage current. 1. A deterioration detection device for a lightning arrester, comprising: thermally responsive means for outputting a deterioration detection signal based on the deterioration of the lightning arrester. 2 As the thermal response means, a low melting point metal is provided near the resistor for leakage current detection, and the melting of the low melting point metal short-circuits the relay contacts and outputs a deterioration detection signal. The deterioration detection device for a lightning arrester according to item 1. 3 As the thermal response means, a thermostat is provided near the resistor for detecting leakage current, and the operation of the thermostat short-circuits the relay contacts and outputs the deterioration detection signal.
A deterioration detection device for a lightning arrester as described in .