JPH03262979A - Internal abnormality detecting method for gas insulation equipment - Google Patents

Abstract

PURPOSE:To securely detect abnormality of a contact part in a tank by providing a reference point where the influence of the contact part is not exerted outside the tank and comparing the temperature at the reference point with the temperature at a measurement point corresponding to each contact part. CONSTITUTION:Temperatures measured by contact type thermometers 85 - 87 of breakers A - C are compared with a reference temperature measured by a thermometer 88 provided at the reference point and when a temperature difference from the reference point is larger than a certain extent, it is judged that the contact part is abnormal. At this time, the range of temperature differences between the measurement points and reference point in a normal contact state is inputted to a comparing means such as a computer previously and then abnormality of any contact part can easily be decided. The temperature differences are measured at constant intervals of time and their variation is monitored to predict the progress of abnormality and the period of repair inspection. Further, the abnormality is detected by comparing the reference point and respective measurement points, so even if plural measurement points become abnormal at the same time, they can accurately be detected.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a method for detecting an internal abnormality in gas-insulated equipment in which a high-voltage charging part is sealed together with an insulating gas inside a closed container. In particular, the present invention relates to a method capable of detecting an abnormality in a contact part provided in a high voltage charging part inside a closed container from the outside.

(Prior art) Gas-insulated equipment, which consists of a high-voltage charging part housed in a sealed container together with an insulating gas such as SF6 gas, has excellent insulation properties and can be made smaller, so it has become popular in modern substations and Widely used in switchyards. However, this gas insulated equipment has a problem in that the live part is enclosed in a sealed container, and therefore the live part cannot be inspected directly from outside the container. In particular, in gas-insulated equipment, the conductors that are live parts are connected to each other inside the container using contact parts, or the contact parts are moved toward and away from each other, such as the fixed contact and movable contact of a switch. Since such a contact abnormality at the contact portion greatly impedes the normal operation of the gas insulated equipment, it is desired to detect such an abnormality from the outside of the closed container at an early stage during the operation of the gas insulated equipment.

The invention described in Japanese Patent Publication No. 1-13300 was proposed in response to such conventional demands, and the abnormality detection method thereof will be explained in detail below with reference to FIG. Figure 2 shows
A grounded tank-type gas circuit breaker with separate phases is used as a gas insulated device for detecting abnormalities, and A, B, and C indicate circuit breakers for each phase, respectively. Each circuit breaker A to C has an insulating gas sealed in a tank 1 which is a hermetically sealed container, and a bushing center conductor 2.
, a stator side conductor 3, and a movable element side conductor 4 are housed.

Further, at the contact portions of the bushing center conductor 2゜2, the stator side conductor 3, or the mover side conductor 4, contact portions 5.6 for electrically connecting each conductor are provided between the stator side conductor 3 and the mover side conductor. A blocking contact portion 7 is provided between the side conductor 4 and the side conductor 4 .

On the outer peripheral surface of each tank 1 of the gas circuit breaker having such a configuration, a contact thermometer 85.
86.87 are provided. For example, when detecting an abnormality in the contact state between the bushing center conductors 2, 2 and the contact portions 5, 6 of the stator side conductor 3 or mover side conductor 4,
Each contact thermometer 85.8 installed on the outer circumferential surface of each tank
Compare the temperatures of 6. Here, if there is no abnormality in each contact part 5, 6, the detected temperature by each thermometer 85, 86 will be the same, but if there is an abnormality in any contact part, the temperature detected by the thermometer corresponding to that contact part will be the same. temperature becomes higher than the temperature of other thermometers. The reason for this is that, as shown in the graph shown in Figure 3, the tank surface temperature at the location corresponding to the abnormal contact increases, as can be seen from the relationship between the electrical resistance R at the first contact and the tank surface temperature T. It depends. Moreover, if the temperature is similarly compared with the temperature at the same point in the other phase circuit breaker installed in parallel, abnormality can be detected even more accurately.

On the other hand, regarding the cutoff contact part 7, due to the occurrence of an arc when the contact part 7 opens and closes, the corresponding thermometer 87 on the outer circumferential surface of the tank is replaced by the other two thermometers 8 that do not involve opening and closing operations.
5.86, it is not abnormal just because the temperature is higher than the temperature of each part of the same circuit breaker. Therefore, an abnormality is detected by comparing the temperature of the thermometer 87 at the location corresponding to the other phase cutoff contact portion 7.

(Problem to be Solved by the Invention) By the way, in the conventional internal abnormality detection method as described above, it is necessary that the electrical resistance of the contact parts of the same structure is the same.
In reality, the specific electrical resistance often differs for each individual contact point, and the measurement of the temperature on the outer circumferential surface of the tank is
It is easily affected by direct sunlight, wind and rain, etc., and it is difficult to say that simply comparing the temperatures of various parts of the tank will necessarily accurately detect abnormalities. In order to compensate for variations in the electrical resistance of the contact parts and the effects of weather, etc.,
This method is difficult because it requires prior measurement of resistance values and temperature rise values, as well as sensors to detect weather conditions.

In addition, if an abnormality occurs at the same time in two contact points of the same type where the temperature is compared, or if the temperature of the tank outer surface corresponding to other contact points increases due to the heat generated at the abnormal point, There is no temperature difference in measurements, and abnormalities cannot be detected.

The purpose of the present invention is to solve the problems of the prior art as described above, eliminate the influence of variations in measurement points due to the specific resistance of the contact part, weather, etc. However, it is an object of the present invention to provide a method for detecting internal abnormalities in gas-insulated equipment that can reliably detect such abnormalities.

[Structure of the Invention] (Means for Solving the Problems) The method for detecting internal abnormalities in gas-insulated equipment of the present invention includes providing a measurement point at a position corresponding to the contact portion on the outer peripheral surface of a sealed container, and detecting the measurement point at a position corresponding to the contact portion. Measure the temperature, set a reference point at a location that is not affected by contact parts inside the sealed container, measure the temperature at this reference point, and correspond to the measurement point from the temperature difference between the temperature at the measurement point and this reference point. This feature is characterized by detecting abnormalities in the contact portion.

(Function) In the present invention having the above configuration, an abnormality is detected by comparing the temperature between a measurement point corresponding to each contact part and a reference point that is not affected by each contact part. , it is possible to reduce variations in electrical resistance of individual contact portions and external influences such as direct sunlight and wind and rain.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to FIG.

In FIG. 1, A, B, and C indicate circuit breakers for each phase, respectively. Each circuit breaker A to C has an insulating gas sealed in a tank 1, which is a sealed container, and a bushing center conductor 2, a stator side conductor 3, and a mover side conductor 4 are housed in this tank 1. ing. Further, at the contact portions between the bushing center conductor 2 and the stator side conductor 3 or the mover side conductor 4, contact portions 5.6 for electrically connecting each conductor are provided. 4, a blocking contact portion 7 is provided.

On the outer peripheral surface of each tank 1 of the gas circuit breaker having such a configuration, there is a contact thermometer 85.
86.87 are provided. Furthermore, in this embodiment, a reference thermometer 88 for measuring the temperature at a reference point is provided separately from the contact thermometer 85.86.87. This reference point shall be placed at a location under the same environmental conditions as the circuit breakers A-C of each phase, and shall be made of a material that exhibits the same temperature changes as tank 1 of each circuit breaker in the same environment. is desirable. Further, this reference point is located away from each of the contact portions and is located at a position that is not affected by heat generation from each of the contact portions during operation of the circuit breaker.

In gas-insulated equipment with such a configuration, each contact thermometer 8 of each circuit breaker A to C must be used to determine the abnormality of the contact part.
Compare the temperature difference between the temperature measured by 5.86.87 and the reference temperature measured by the thermometer 88 installed at this reference point, and if the temperature difference from the reference point is larger than a certain level, the contact part It is determined that an abnormality has occurred. At this time,
If the range of temperature difference between the measurement point and the reference point in a normal contact state is input in advance into a comparison means such as a computer, abnormality can be easily determined regardless of the contact part. Furthermore, by measuring the temperature difference at regular intervals and monitoring the changes, it is also possible to predict the development of an abnormality and the timing of repairs and inspections. Furthermore, since an abnormality is detected by comparing the reference point and each measurement point, even if an abnormality occurs at a plurality of measurement points at the same time, it can be detected accurately. In particular, in this embodiment, the reference point is made of the same material as the tank and is located at a location with the same climatic conditions as the tank, so that the influence of weather, particularly sunlight conditions, can be eliminated.

(Other Embodiments) In the above embodiments, the reference point was made of the same material as the tank, but it is also possible to simply measure the outside temperature around the tank installation location at the reference point.

[Effects of the Invention] As described above, according to the internal abnormality detection method for gas insulated equipment of the present invention, a reference point that is not affected by contact parts is provided outside the tank, and the temperature of this reference point is matched to each contact part. Despite the simple method of comparing the temperatures at measurement points, it is effective in reliably detecting abnormalities in contact parts inside the tank.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an embodiment of the method for detecting internal abnormality in gas-insulated equipment according to the present invention, Fig. 2 is a cross-sectional view showing a conventional abnormality detection method, and Fig. 3 is a cross-sectional view showing the resistance of the contact portion and its temperature change. This is a graph showing. 1...Tank, 2...Bushing center conductor, 3...
・Stator side conductor, 4... Mover side conductor, 5, 6...
Contact part, 7... Breaking contact part, 85.86.87...
Thermometer provided at the measurement point, 88...Thermometer provided at the reference point.

Claims (1)

[Claims] In a method for detecting an internal abnormality in a gas-insulated device, the method includes storing a current-carrying conductor and its contact portion in a closed container, and sealing an insulating gas in the closed container, wherein the contact portion corresponds to the contact portion on the outer peripheral surface of the closed container. A measurement point is set up at a location, the temperature at this measurement point is measured, a reference point is set up at a location not affected by the contact part inside the sealed container, the temperature at this reference point is measured, and the temperature at the measurement point and the temperature at the reference point are measured. A method for detecting an internal abnormality in gas-insulated equipment, characterized by detecting an abnormality in a contact part corresponding to a measurement point from the temperature difference between the reference points.