JPH0559647B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to an apparatus for automatically analyzing and data processing flammable gas dissolved in insulating oil of oil-immersed equipment, such as an oil-immersed transformer. This invention relates to an automatic gas-in-oil analyzer that has a function for determining abnormalities based on the increasing tendency of combustible gas.

[Prior art] When an abnormality such as arc discharge, corona discharge, or local heating occurs inside oil-immersed equipment, electrical insulating materials such as insulating oil or insulating paper near the abnormality decompose and generate flammable gas. do. Most of this generated flammable gas is dissolved in the insulating oil. Therefore, combustible gas analysis in oil has traditionally been carried out in order to detect abnormalities in oil-immersed equipment at an early stage and prevent accidents from occurring. Conventionally, the mainstream method for detecting flammable gases in oil has been off-line processing in which a person extracts oil from an oil-immersed device and analyzes the extracted oil using an analytical device such as gas chromatography.
In recent years, automatic online analysis devices that are connected to a transformer and automatically perform everything from oil sampling to analysis have been commercialized.

However, although both analyzers can detect the absolute value of the amount of flammable gas in oil, the increase in the amount of flammable gas in oil is another important factor for early detection of abnormalities in oil-filled equipment. Processing to determine trends was not possible, and all trend detection and determination of the presence or absence of abnormalities had to be done manually. The first method for predicting abnormalities in oil-filled equipment based on the increasing trend of the amount of flammable gas in oil is
As shown in the figure, whereas the abnormality prediction method based only on the absolute value of the amount of combustible gas in oil detects an abnormality at time t ₂ , the abnormality can be detected at time t ₁ before time t ₂ .
Although this is an effective method for earlier detection than the latter, it has the disadvantage that conventional methods require human labor to collect and process data, and require skill to detect trends and determine the presence or absence of anomalies. Ta.

[Summary of the Invention] In order to eliminate the drawbacks of the conventional combustible gas analyzer in oil, the present invention performs statistical processing on the analysis results to determine the trend of change over time, and then compares the trend with the reference trend. The object of the present invention is to provide an automatic gas-in-oil analyzer that has the function of comparing the two to determine whether or not there is an abnormality in oil-filled equipment.

[Embodiment of the Invention] Fig. 2 is a block diagram showing an embodiment applied to an oil-immersed transformer of the present invention, and 1 is an oil-immersed transformer;
2 is the insulating oil in this oil-immersed transformer 1; 3 is an oil sampling pipe for drawing the insulating oil 2 from the oil-immersed transformer 1 to the gas extraction part of the automatic gas-in-oil analyzer 4; 7 is the oil sampling pipe of the controller 5. A valve driving device opens and closes the valve 6 according to a signal; 8 is a gas extraction section that takes in the insulating oil 2 and extracts flammable gas from the oil; 9 is this gas extraction section 8
10 is a gas analysis section that detects the amount of combustible gas by taking in the combustible gas extracted by 11 is a display unit that displays data processing results; 11 is a display unit that displays the data processing results; 11 is a data processing unit that calculates the tendency of change over time of combustible gas by statistical processing such as the square method, and compares the trend with a reference trend to determine the presence or absence of an abnormality; is an alarm output unit, and 7 to 12 are operated by the control unit 5 in an appropriate order.
In the figure, solid arrow lines indicate the flow of extracted combustible gas, dotted lines indicate the flow of data, and dashed lines indicate the flow of control signals.

The automatic gas-in-oil analyzer 4 configured as described above starts the valve drive device 7 from the control unit 5 at regular intervals to open and close the valve 6, thereby
A certain amount of insulating oil 2 is drawn into the gas extraction section 8 through the oil sampling pipe 3. Next, the gas extraction section 8
When a start signal is received from the insulating oil 2, flammable gas is extracted from the insulating oil 2, the extracted flammable gas is sent to the gas analysis section 9, and a completion signal is transmitted to the control section 5.
Upon receiving the gas analysis start signal from the control unit 5, the gas analysis unit 9 measures the total amount of flammable gas or the amount of several types of specific combustible gases such as C ₂ H ₂ (acetylene), and converts this measurement data into data. It is transmitted to the processing section 10 and also outputs a completion signal to the control section 5. next,
When the control unit 5 activates the data processing unit 10,
The data processing unit 10 performs statistical processing using the least squares method or the like to remove measurement variations including the latest data and several past data that have already been stored. Determine the increasing trend of the amount of flammable gas over a certain period of time, compare this increasing trend of the amount of flammable gas with a preset standard trend, and determine whether there is an abnormality.
The arithmetic processing result is output to the display unit 11, and the presence or absence of an abnormality and a processing completion signal are output to the control unit 5. The display unit 11 receives a display operation signal from the control unit 5, displays the calculation processing result, and outputs the alarm output unit 1.
2 receives an abnormality occurrence signal from the control unit 5 and outputs an alarm such as a contact output.

In the above embodiment, the presence or absence of an abnormality is determined by focusing on the increasing trend (and decreasing trend) of the total amount of flammable gas in oil or the amount of specific several types of combustible gas, but the data processing unit 10 Considering that gas analysis accuracy is poor when the amount of combustible gas is small, we use data that shows the amount of flammable gas above a certain sensitivity level to prevent misjudgments when the amount of combustible gas is small. It is configured.

[Effects of the Invention] As explained above, the present invention is a device that automatically analyzes the amount of flammable gas dissolved in the oil of oil-immersed equipment. Since it has the function of determining trends in oil-immersed equipment and determining the presence or absence of abnormalities in oil-immersed equipment, it has the effect of eliminating the need for manpower and skill that were conventionally required for data processing and determining the presence or absence of abnormalities.

[Brief explanation of drawings]

FIG. 1 is a characteristic curve of the change over time in the amount of combustible gas in oil, and FIG. 2 is a block diagram showing an embodiment of the present invention. In the figure, 1 is an oil-immersed transformer, 2 is an insulating oil, and 3 is an oil-immersed transformer.
4 is an oil extraction pipe, 4 is an automatic gas-in-oil analyzer, 5 is a control unit, 6 is a valve, 7 is a valve drive device, 8 is a gas extraction unit, 9 is a gas analysis unit, 10 is a data processing unit, and 11 is a display unit , 12 indicates an alarm output section. In each figure, the same reference numerals indicate the same or equivalent parts. .

Claims (1)

[Claims] 1. A gas extraction unit that takes in a small amount of oil from oil-filled equipment and extracts the flammable gas contained in this oil, and a gas extraction unit that extracts the flammable gas contained in the oil, and A gas analysis section analyzes the amount of oil, and the analysis results are input, and statistical processing is performed to remove variations in measurements, including past data, to determine trends in changes over time, and the trends are compared with standard trends to determine the oil level. An automatic gas-in-oil analyzer characterized by comprising a data processing unit that determines whether there is an abnormality in input equipment and outputs the result.