JPH0552787A - Device for measuring dissolved gas within oil - Google Patents

Abstract

PURPOSE:To enable a local overheating and an abnormality due to a discharge phenomenon to be detected simultaneously and a diagnosis performance of an oil electrical equipment to be improved by installing a hydrogen gas sensor and an acetylene gas sensor and by measuring a concentration of hydrogen gas and that of acetylene gas simultaneously in a circulation bubbling process. CONSTITUTION:A sample oil 2 is taken into a gas extraction container 1, an air pump 5 is driven for allowing air to be fed to a circulation system containing the container 1, and then the sample oil 2 is subjected to bubbling, thus enabling an air bubble to be generated from an air bubble generation portion 3, hydrogen gas and acetylene gas within the sample oil 2 to be discharged into air within the container 1, and this procedure to be continued for a specified amount of time for bringing a concentration of an air liquid closer to a balanced value. This balanced value is measured by a hydrogen gas sensor 7 and an acetylene gas sensor 8, is converted to a gas concentration within oil, and is displayed at indicators 11 and 12. When the measurement is completed, a solenoid valve 4 is released and the air pump 5 is driven and then an extracted gas within oil is discharged, thus enabling an inside of the system to be cleaned and an indication value of each sensor to be returned to an initial value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring dissolved gas in oil.

[0002]

2. Description of the Related Art Conventionally, as means for detecting an abnormality in an oil-filled electric device, insulating oil taken from the electric device is used as a sample oil, air is introduced into the sample oil to perform circulation bubbling, and then the sample oil is introduced into the oil. The concentration of dissolved hydrogen gas is detected by a hydrogen gas measuring instrument, and the abnormality of oil-filled electrical equipment is detected from the detected concentration.

By the way, as an abnormal occurrence of the oil-filled electrical equipment, empirically, local overheating and discharge phenomenon can be mentioned. When local overheating occurs, insulating oil and insulating paper are thermally decomposed, and CH4, C2H4, CO, and CO2 are generated in addition to hydrogen gas.
When electric discharge occurs, acetylene gas is mainly generated in addition to hydrogen gas. Therefore, the hydrogen gas measuring device can detect the occurrence of overheating and discharge phenomenon.
Since the concentration of hydrogen gas generated by the occurrence of minute discharges is low, it is difficult to determine the abnormality due to this.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to make it possible to simultaneously measure anomalies due to local overheating and discharge phenomena from sampled oil samples, thereby improving the diagnostic performance of oil-filled electrical equipment.

[0005]

Means for Solving the Problems The present invention is an apparatus for measuring dissolved gas in oil using means for dissolved gas in oil by circulating bubbling, wherein both a hydrogen gas sensor and an acetylene gas sensor are provided in the bubbling circulation path. It is characterized in that both sensors are installed and the concentration of hydrogen gas and the concentration of acetylene gas are simultaneously detected by the both sensors during the circulation bubbling.

[0006]

Embodiments of the present invention will be described with reference to the drawings. Figure 1
In the figure, 1 is a gas extraction container for containing insulating oil sampled from oil-filled electrical equipment as sample oil 2, 3 is a bubble generating part, 4 is a solenoid valve for intake and exhaust, 5 is an air pump, 6 is a sensor chamber, 7 is A hydrogen gas sensor, 8 is an acetylene gas sensor, 9 and 10 are amplifiers, and 11 and 12 are indicators. The output from each sensor is the respective amplifier 9, 1
It is amplified by 0, and the concentration is instructed to the respective indicators 11, 12.

FIG. 2 shows a detailed example of the sensor chamber 6. The hydrogen gas sensor 7 is installed in the hydrogen sensor chamber 61.
Is installed. Here, a semiconductor sensor, for example, a SnO 2 based semiconductor sensor is used as the hydrogen gas sensor 7.

As the acetylene sensor, a non-dispersion type (wavelength 13.7 μm) infrared detector 13 is used. As the infrared radiation source 14, a ceramic heater (500 °
K) as a spectral filter 15, a ZnSe type filter having a spectral characteristic of 13.7 μm ± 0.1 μm and a transmittance of 60%, a pyroelectric infrared sensor as the light receiving element 16, and a chopper 17. , And those having a chopper frequency of 1 Hz were used. Reference numeral 18 is a gas cell into which the gas to be measured is introduced.

First, the sample oil 2 is put into the gas extraction container 1, the air pump 5 is driven, and air is sent into the circulation system including the gas extraction container 1 to bubble the sample oil 2. As a result, bubbles are generated from the bubble generator 3, and hydrogen gas and acetylene gas in the sample oil 2 are released into the air in the gas extraction container 1. By continuing this for a predetermined time, the concentration of gas-liquid reaches an equilibrium value.

The equilibrium value is detected by each of the sensors 7 and 8 and converted into the gas concentration in oil to obtain each indicator 11,
12 is displayed. When this measurement is completed, the intake port and the exhaust port of the solenoid valve 4 are opened, and then the air pump 5 is driven to discharge the extracted gas in oil to the outside of the system. As a result, the inside of the system is cleaned and the indicated value of each sensor returns to the initial value. After this, the measurement of the next sample oil is started.

FIG. 3 shows another embodiment of the present invention. Here, the hydrogen gas sensor 7 is installed in a part of the gas cell 18, so that both sensor chambers are integrated. With such a configuration, the entire configuration can be downsized, which is convenient.

Next, the experiment conducted by the present inventor will be described. 90 ml sample oil, 180 ml total volume in the system, 11 / min flow rate by air pump, diameter of bubble generating part 2
When the measurement was performed using each sensor described above, the concentration of gas-liquid reached the equilibrium value in about 2 minutes. With this configuration, the concentration measurement range is 10 to 2000 pp with hydrogen gas.
m and acetylene gas were 2 to 100 ppm.

[0013]

As described above in detail, according to the present invention, when measuring the concentration of dissolved gas in oil, a sensor for measuring both the hydrogen gas concentration and the acetylene gas concentration is installed. With the measurement operation of, at the same time with hydrogen gas,
As a result, it becomes possible to measure the concentration of acetylene gas, and therefore it is possible to simultaneously diagnose both local overheating and electric discharge phenomenon of electric equipment.

[Brief description of drawings]

FIG. 1 is a layout view showing an embodiment of the present invention.

FIG. 2 is a partial detailed layout diagram of FIG.

FIG. 3 is an arrangement diagram showing a modification example of FIG.

[Explanation of symbols]

 1 Gas extraction container 2 Sample oil 3 Air bubble generation part 5 Air pump 6 Sensor chamber 7 Hydrogen gas sensor 8 Acetylene gas sensor

Claims (1)

[Claims] 1. An apparatus for measuring dissolved gas in oil using means for dissolved gas in oil by circulating bubbling, wherein both a hydrogen gas sensor and an acetylene gas sensor are installed in the bubbling circulation path, and the both sensors are used to perform the An apparatus for measuring dissolved gas in oil, which detects both the concentration of hydrogen gas and the concentration of acetylene gas at the same time during the circulation bubbling.