JP3103450B2 - Soil detection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting contamination used for grasping the amount of contamination of an insulator device for insulating and supporting an overhead transmission line.

[0002]

2. Description of the Related Art If the surface of an insulator device is contaminated by attached salt, the insulating property is reduced. Therefore, it is necessary to keep track of the amount of contamination of the insulator device for maintenance of an overhead transmission line. Therefore, a fouling detection sensor installed near the insulator device has been conventionally known.

A typical example of this type of fouling detection sensor is, for example, as disclosed in Japanese Utility Model Laid-Open Publication No. Sho 62-88951, based on the resistance between electrodes on an insulating plate, the amount of equivalent salt deposited on the insulating plate. A method has been devised in which the insulating plate is electronically cooled during measurement to cause dew condensation, and the leakage current is measured even when the electrodes are moistened.

However, this type of conventional fouling detection sensor is
Since it is necessary to wet the entirety of the electrodes that are widely distributed on the insulating plate, it is inevitable that some parts will be excessively wet, and the leakage current between the electrodes will change and measurement will be performed The accuracy tended to decrease. In order to avoid this, if wetting is suppressed, insufficient wetting occurs partially, and the measurement ends before the leakage current between the electrodes reaches saturation, which also tends to lower the measurement accuracy.

The inventor of the present invention arranged a large number of electrodes 2 in a matrix on an insulating plate 1 as shown in FIG. Developing a fouling detection sensor that detects the leakage current between the two, performs this operation between all the electrodes, and then calculates the equivalent amount of salt deposition from the entire resistance distribution on the insulating plate 1. is there.

[0006] However, in this method of detecting fouling by the fouling detection sensor, the measurement is terminated at a certain time after the start of wetting,
Since the measurement value for each electrode at that time was adopted, some parts on the insulating plate were not sufficiently wetted, and the value before the leakage current reached saturation might be used as the measurement value. There is a disadvantage that the detection accuracy is reduced. In addition, if wetting each electrode for a sufficient time to prevent this drawback, it takes a long time for measurement, making it impossible to cope with rapid soiling such as a typhoon, and also wetting the insulating plate. However, there is also a problem that the electronic cooling device needs to be energized for a long time, and the size of the battery must be increased.

[0007]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and accurately measures the leakage current between a large number of electrodes widely distributed on an insulating plate in a relatively short time. It has been completed in order to provide a fouling detection method capable of performing the method.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to measure a leak current by sequentially applying a voltage between a large number of electrodes arranged on an insulating plate. upon computing the equivalent salt adhesion from the measured value distribution of the whole above, when the leakage current after wetting the start of a plurality of ambient humidity
Of the ambient humidity during measurement from the characteristic curve
Select response characteristics curve, saturation of the leakage current after wet start
It is characterized in that a leakage current saturation value is predicted based on a measured value of the leakage current earlier than time and a selected characteristic curve.

[0009]

According to the present invention, the characteristic curve representing the change in the leakage current after the start of wetting draws a specific shape depending on the ambient humidity and the like, and is compared with the saturation time of the leakage current after the start of wetting.
The saturation value is predicted based on the measured value of the leakage current at a relatively early stage and the characteristic curve. For this reason, it is not necessary to perform wetting for a long time as in the related art and to measure the saturation value of the leakage current, so that the amount of adhered permeated salt indicating contamination can be accurately known in a relatively short time. In addition, the time required to energize the electronic cooling device for wetting the insulating plate can be shortened, so that the size of the battery can be reduced.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to the illustrated embodiments. FIG. 1 is a view showing the overall configuration of a fouling detection sensor, wherein 1 is an insulating plate made of the same ceramic material as the insulator, and 2 is a large number of electrodes arranged on the insulating plate 1 in a matrix. . Each electrode 2 is connected to horizontal and vertical switch circuits 3,4. Here, analog switches and relay contacts are used as the switch circuits 3 and 4. By sequentially switching these switch circuits 3 and 4, each electrode 2 is selected one after another and electrically connected to lines 5 and 6. It can be connected.

Lines 5 and 6 are connected to a measuring power source 7 and a measuring resistor 8, and measure the current flowing through the measuring resistor 8 to select the electrodes 2 selected by the switch circuits 3 and 4.
The leakage current flows through the circuit and is generated as an electromotive voltage proportional to the leakage current. Then, the voltage value at both ends of the measuring resistor 8 is converted into a digital value by the A / D converter 9 and input to the arithmetic unit 10. A device that wets the contaminants on the insulating plate 1, such as an electronic cooling device 11 using a solar cell as a power source, is attached to the back surface of the insulating plate 1 so that the insulating plate 1 can be wetted. ing.

In the present invention, the ambient humidity at the time of measurement is first measured as shown in the flow sheet of FIG. Since the characteristic curve representing the change of the leakage current after the start of wetting according to the ambient humidity has a specific shape, it is possible to know what characteristic curve to draw when the ambient humidity is known. For example, FIG.
7 is a characteristic curve of leakage current when the relative humidity RT is 55%, 65%, and 85% in the case of FIG. The arithmetic unit 10 stores many such characteristic curve shapes, and selects a characteristic curve according to the measured ambient humidity.

Next, energization of the electronic cooling device 11 is started, and while the insulating plate 1 is moistened, leakage current is measured while sequentially energizing a large number of electrode pairs. For example, when the relative humidity is 65%, it takes about 300 seconds for the leakage current to reach the saturation value as shown in FIG. However, in the present invention, the saturation value of the leakage current is predicted from the leakage current value and the shape of the selected characteristic curve at a relatively early time after the start of wetting, for example, at the lapse of 100 seconds. This operation is performed for all electrode pairs, and the obtained predicted values are statistically averaged to calculate the amount of contamination.

For this reason, it is not necessary to perform wetting until saturation is reached over a long period of time as in the prior art, and the amount of contamination can be known very accurately in a relatively short time. In addition, since the time for energizing the electronic cooling device can be reduced, the size of a solar cell or the like serving as a power supply can be reduced.

Although the leakage current is measured for all the electrode pairs in the flow of FIG. 2, when the saturation does not reach when the leakage current value and the ambient humidity are measured within a certain set time. Alternatively, when there is almost no change in the measured value, the predicted value can be canceled, and the contamination amount can be evaluated using only the other predicted values. With this method, it is possible to reduce the variation in the predicted value due to the unevenness of the wetting, and it is possible to perform the evaluation based on only the ideal predicted value in a sufficiently wet state.

[0016]

As described above, according to the method of the present invention, the leakage current between a large number of electrodes widely distributed on an insulating plate can be accurately measured in a relatively short time, and a typhoon can be obtained. It can respond to rapid contamination such as time. Further, since the time for energizing the electronic cooling device or the like can be reduced, the size of the solar cell or the like serving as a power supply can be reduced. Therefore, the present invention has an extremely large contribution to industrial development as a fouling detection method which has solved the conventional problems.

[Brief description of the drawings]

FIG. 1 is a plan view showing a contamination measuring device.

FIG. 2 is a flow sheet of an example of the present invention.

FIG. 3 is a graph showing a leakage current characteristic curve.

[Explanation of symbols]

 1 insulating plate 2 electrodes

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Nagae Nagaue 3-150 Omoyama, Tenpaku-ku, Nagoya City, Aichi Prefecture (56) References JP-A-62-2669 (JP, A) (JP, U) Japanese Utility Model Showa 62-170559 (JP, U) Japanese Utility Model Showa 60-125568 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 27/00-27 / 10 H01B 17/00-17/54 H02G 1/02

Claims (1)

(57) [Claims] Upon 1. A measuring current leakage by applying sequentially voltages between a plurality of electrodes disposed on the insulating plate, and calculates the equivalent Salt Adhesion from the measured value distribution of the whole on the insulating plate, a plurality
The characteristic curve corresponding to the ambient humidity at the time of measurement is selected from the characteristic curves representing the time change of the leakage current after the start of the wetting at the ambient humidity, and the leakage current after the start of the wetting is saturated. Relative to time
A contamination detection method, wherein a saturation value of the leakage current is predicted based on a measured value of the leakage current at an earlier time and a selected characteristic curve.