WO2012097488A1

WO2012097488A1 - Calibration device for on-line sulfur hexafluoride humidity meters and calibration method therefor

Info

Publication number: WO2012097488A1
Application number: PCT/CN2011/001589
Authority: WO
Inventors: 唐平; 苏长华; 王锴; 胡仕红; 王杰
Original assignee: 四川电力科学研究院
Priority date: 2011-01-19
Filing date: 2011-09-19
Publication date: 2012-07-26
Also published as: CN102169113A; DE212011100059U1; DE112011100765T5; DE112011100765B4; CN102169113B

Abstract

A calibration device for online sulfur hexafluoride humidity meter and a calibration method therefor. A gas storage tank (1) is connected to a calibration chamber (3) via a gas outlet pipe; a calibration inlet valve (5) is disposed on the gas outlet pipe; the calibration chamber (3) is connected to a circulation pump chamber (4) via a pipe; a communication valve (7), a gas discharge valve (8) and a discharged gas flow meter (14) are sequentially disposed on the gas discharge pipe of the circulation pump chamber (4); an outlet pipe of the circulation pump chamber (4) is connected to the gas storage tank (1); an outlet valve (6) is disposed on the outlet pipe; a diaphragm pump (13) is disposed inside the circulation pump chamber (4); a circulation pressure gauge (11) is disposed on the circulation pump chamber (4); an interface (12) for connecting a humidity sensor to be calibrated is disposed on the calibration chamber (3). A pressure gauge (15) is disposed on the gas storage tank (1); a gas inlet pipe is disposed on the gas storage tank (1); and a gas inlet valve (16) is disposed on the gas inlet pipe. A vacuum pump (2) is connected to the gas storage tank (1) via a vacuuming pipe; a vacuum pump gas inlet valve (9) is disposed on the vacuuming pipe. The device can measure and compare the online sulfur hexafluoride humidity meters at different gas pressures and different humidity conditions, significantly increasing the accuracy of online humidity meters.

Description

Sulphur hexafluoride online humidity meter calibration device and verification method thereof

The invention relates to a calibration device for detecting a humidity meter, in particular to a calibration device for a sulfur hexafluoride online humidity meter.

Background technology

Sulfur hexafluoride is an insulating gas and an arc extinguishing gas in high-voltage electrical equipment. The humidity of the sulphur hexafluoride gas directly affects its insulation properties. Accurate online measurement of the humidity of sulphur hexafluoride gas plays a vital role in ensuring the safety of gas-filled electrical equipment. However, the comparison and verification of the sulfur fluoride humidity sensor widely used in substations and lines are carried out under normal pressure, and the measurement accuracy under the working condition of the book cannot be guaranteed. At the same time, due to the structural reasons of the humidity measuring device, the gas detected by the sensor is not consistent with the standard gas during the comparison and calibration.

Summary of the invention

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sulphur hexafluoride on-line hygrometer calibration apparatus for performing alignment and inspection of an on-line hygrometer operating under different gas pressures and different humidity conditions.

The object of the present invention is achieved as follows: a sulphur hexafluoride on-line hygrometer calibration device, the gas storage tank is connected to the calibration chamber through an gas outlet pipe, and the gas outlet pipe is provided with a check inlet pottery, and the check tank is subjected to a pipeline. Connected to the circulating pump chamber, a circulation valve and an exhaust valve and an exhaust flow meter are sequentially arranged on the exhaust pipe of the circulating pump chamber, and an outlet pipe of the circulating pump chamber is connected with the gas storage tank, and an outlet valve is arranged on the outlet pipe The diaphragm pump is disposed in the circulating pump chamber, and the circulating pump chamber is provided with a circulating pressure gauge, and the calibration chamber is provided with an interface for connecting the verified humidity sensor; the gas tank is provided with a pressure gauge, and the gas tank is provided There is an intake pipe, and an intake pipe is provided on the intake pipe; the vacuum pump is connected to the gas storage tank through a vacuum pumping pipe, and a vacuum pump intake valve is arranged on the vacuum pumping pipe.

A safety valve is arranged on the above gas tank.

The pressure gauge and the circulating pressure gauge described above are vacuum positive pressure dual pressure gauges; the gas tank, the vacuum pump, the calibration chamber and the circulation pump chamber are all mounted on the movable frame.

Another object of the present invention is to provide a method of verifying the above apparatus.

Another object of the present invention is achieved by a method for verifying a sulfur hexafluoride on-line hygrometer calibration device, which is carried out as follows: Say m book

a) System drying:

Close the contact valve, exhaust valve, intake valve, open the check inlet valve, outlet valve and vacuum pump intake valve, start the diaphragm pump and vacuum pump, pump to the circulating pressure gauge and pressure gauge indication - 0. 08MPa, stop the vacuum pump, Close the vacuum pump intake valve, inject dry nitrogen from the inlet air to the circulating pressure gauge and the pressure gauge indication 1. 2 MPa _; close the intake valve by opening the contact valve and the exhaust valve to 0. 12MPa _; Close the vacuum pump intake valve after the system has dried.

b) static gas distribution - by calculation, quantitative injection of water vapor from the intake valve and dry nitrogen to the gas in the tank to achieve the required pressure;

c) Calibration:

After the gas circulation in the system is 5 minutes, open the contact valve and the exhaust valve, and vent the gas at a speed of 0.2 L/rai.n for 2 minutes, and then check the gas moisture in the gas tank from the outlet of the exhaust flow meter;

d) Check:

Close the check inlet valve and the outlet valve, open the contact valve, release the pressure from the check chamber and the circulating pump chamber from the exhaust valve, unmount the check chamber interface, and connect the verified humidity sensor;

Open the check inlet width, clean the check chamber and the circulating pump tank at a speed of 0.5 L/min for 5 minutes, open the outlet valve, close the contact valve and the exhaust valve, and cycle for 2 minutes;

Open the contact valve, close the check inlet valve and outlet valve, open the exhaust valve to reduce the pressure of the calibration chamber and the circulating pump chamber to the working pressure of the humidity sensor, verify the humidity sensor, and press the pressure from high to low. Checkpoint

Adjust the humidity of the gas in the gas tank by drying the nitrogen, repeat the calibration and calibration process, and complete the verification of different humidity;

Repeat the above process after replacing the sensor;

The above negative pressure is the actual pressure, and the positive pressure is the gauge pressure.

The gas with a certain humidity is fully circulated in the comparison device to stabilize the humidity of the entire device. The alignment of the online humidity measuring device after calibration with the standard humidity measurement method. The device can realize the comparison of different humidity and different humidity of the online humidity measuring device, and significantly improve the accuracy of the online humidity measuring device.

The invention performs on-site (laboratory) simulation of sulfur hexafluoride gas sample to form stable moisture Nm book

Standard gas sample.

The specific realization process of the present invention is as follows: a certain amount of water gas is added into the gas storage tank, and the dry gas is added to adjust the moisture content in the gas storage tank, and the gas pressure in the gas storage tank is higher than the working pressure of the sulfur hexafluoride gas humidity sensor. The on-line device is calibrated using the humidity measured accurately by standard methods as a reference. The working pressure of the humidity sensor is changed, and the online humidity measuring device measures the same humidity gas under different pressures, and the adaptability of the online humidity measuring device to the pressure change in the actual operating environment is examined. Use different humidity standards to check the accuracy of the online humidity measurement device. The device is mainly composed of a gas tank, a vacuum pump, a gas circulation system, a pressure control system, a pressure regulation system, a sampling and a nesting system.

The entire unit is mounted on a reliable, movable frame for mobility.

The working principle of the invention:

The gas tank is first dried by vacuuming and dry gas cleaning to maintain the required vacuum. A certain volume of saturated gas and dry gas are metered into the gas tank according to the volume of the gas tank, the ambient temperature, and the preset gas pressure in the gas tank, and the set maximum humidity. Connect the entire system piping and start the circulation unit to make the humidity of all gases in the gas space inside the system uniform. The gas humidity is measured by the gravimetric method or the precision dew point method, and the calibration is completed to obtain the standard gas. Close the gas inlet port of the gas storage tank to adjust the working pressure of the humidity sensor. The online humidity measuring device measures the same humidity gas under different pressures, and examines the adaptability of the online humidity measuring device to pressure changes. After replacing the online humidity measuring device, the external system is thoroughly cleaned with standard gas, and the gas is circulated throughout the system. This cycle is repeated to complete the stability of the humidity measurement when multiple online humidity measuring devices simulate the pressure changes in the actual operating environment.

Repeat the above procedure after changing the humidity of the gas to check the accuracy of the online humidity measuring device to measure different humidity.

The invention has the following performance characteristics and advantages:

1. Simulate the working environment of sulphur hexafluoride sensor: Use the higher pressure moisture gas to check the hexafluoride sulphur humidity online device, so that the calibration is carried out under the working condition, and the reliability of the online device monitoring data is improved.

2. Statically formulated standard gas: Statically formulated standard gas is calibrated by standard method to overcome the fluctuation of dynamic gas distribution humidity and reduce the factors affecting humidity.

3. Standard gas humidity is stable: High-pressure closed system overcomes the standard gas humidity change that may occur under normal pressure due to the difference in humidity between ambient air and standard gas. The standard gas humidity is stable and meets the entire calibration requirements.

4. Large standard gas volume: A large amount of standard gas can be prepared at one time to verify multiple online devices.

5. Convenient operation: After vacuuming the gas storage tank, it is easy to dry the gas storage tank. Using vacuum, square Talking about friends

The high humidity gas is injected into the gas tank and the standard gas humidity is adjusted.

6, the main technical parameters and performance indicators:

Circulating flow: 300L/h (under gas tank pressure);

Gas storage capacity: 20L ( 1. 2MPa) _;

Working pressure (gauge pressure): 0 MPa~0. 8MPa;

Working noise: ^45dB (A);

Dimensions: 800 X 750 X 450mm. DRAWINGS

Figure 1 is a simplified diagram of the system process equipment of the apparatus.

Figure 2 is a layout view of the process equipment shown in Figure 1.

3 and 4 are respectively a left side view and a top view view of Fig. 2. detailed description

Figure 1 shows a sulphur hexafluoride on-line hygrometer calibration device. The gas storage tank 1 is connected to the calibration chamber 3 via an outlet pipe. The outlet pipe is provided with a check inlet valve 5, and the check tank is connected to the pipe. The circulation pump chamber 4 is connected, and a communication valve 7 and an exhaust valve 8 and an exhaust flow meter 14 are sequentially disposed on the exhaust pipe of the circulation pump chamber, and an outlet pipe of the circulation pump chamber is connected with the gas storage tank 1, and the outlet pipe is connected An outlet wall 6 is provided, a diaphragm pump 13 is disposed in the circulation pump chamber 4, a circulation pressure gauge 11 is disposed on the circulation pump chamber 4, and an interface 12 for connecting the verified humidity sensor is disposed on the calibration chamber 3; There is a pressure gauge 15 on the first, an air inlet pipe is arranged on the gas storage tank 1, and an intake valve 16 is arranged on the air inlet pipe; the vacuum pump is connected with the gas storage tank 1 through a vacuum pumping line, and a vacuum pump inlet valve 9 is arranged on the vacuum pumping pipeline. . A safety valve 10 is provided on the gas tank 1. The pressure gauge 15 and the circulating pressure gauge 11 are both vacuum positive pressure dual-purpose pressure gauges; the gas storage tank 1, the vacuum pump 2, the calibration chamber 3, and the circulation pump chamber 4 are all mounted on a movable frame. '

Referring to Figure 2, Figure 3, Figure 4, the entire equipment is placed on a movable frame. The length X of the frame is 810 X 710 (Fig. 4) and the height is 900 匪 (Fig. 2).

A method for verifying a sulphur hexafluoride on-line hygrometer calibration device is carried out as follows: a) System drying:

Close the contact valve 7, the exhaust valve 8, the intake valve 16, open the check inlet valve 5, the outlet valve 6 and the vacuum pump intake valve 9, activate the diaphragm pump 13 and the vacuum pump 2, pump the air to the circulating pressure gauge 11 and the pressure gauge 15 indicates -0. 08MPa, stop the vacuum pump, close the vacuum pump intake valve 9, and inject dry nitrogen from the intake valve 16 Say m book

Ring pressure gauge 11 and pressure gauge 15 indicate 1.2 MPa _; by opening the contact valve 7 and the exhaust valve 8 to relieve pressure to 0. 12MPa, closing the intake valve 16; doing this three times, after the system is dried, the vacuum pump intake valve is closed 9.

b) Static gas distribution:

By calculation, the water vapor is metered from the intake valve 16 and the nitrogen gas is dried to the desired pressure in the tank;

c) Calibration:

After the gas circulation in the system is 5 minutes, the contact valve 7 and the exhaust valve 8 are opened, and the gas is vented at a speed of 0.2 L/min for 2 minutes, and then the gas in the gas tank is sampled and detected from the outlet of the exhaust gas flow meter 14;

d) Check:

Close the check inlet valve 5. Open the outlet valve 6. Open the contact valve. 7. Release the pressure from the check chamber and the circulating pump chamber from the exhaust valve 8. Disconnect the check chamber interface and connect the verified humidity sensor.

Open the check inlet valve 5, clean the check chamber and the circulating pump chamber at a speed of 0.5 L/min _{n for} 5 minutes, open the outlet valve 6, close the contact valve 7 and the exhaust valve 8, and circulate for 2 minutes;

Open the contact valve 7, close the check inlet valve 5 and the outlet width 6. Open the exhaust valve 8 to reduce the pressure of the calibration chamber and the circulating pump chamber to the working pressure of the humidity sensor, verify the humidity sensor, and press the pressure from high to low. Humidity sensor multi-pressure point check;

Adjusting the humidity of the gas in the gas tank by drying the nitrogen, repeating the calibration and calibration process, and verifying the different humidity;

Repeat the above process after replacing the sensor;

Claims

杈*J request

1. A sulphur hexafluoride online humidity meter calibration device, characterized in that: a gas storage tank (1) is connected to a calibration chamber (3) via an outlet pipe, and a verification inlet valve (5) is arranged on the gas outlet pipe. The calibration chamber is connected to the circulating pump chamber (4) via a pipeline, and the communication valve (7) and the exhaust valve (8) and the exhaust flow meter (14) are sequentially arranged on the exhaust pipe of the circulating pump chamber, and the circulating pump is provided. The outlet pipe of the silo is connected to the gas tank (1), which is provided with an outlet valve (6), the diaphragm pump (13) is arranged in the circulating pump tank (4), and the circulation pump tank (4) is provided with a circulation. The pressure gauge (11), the calibration chamber (3) is provided with an interface (12) for connecting the verified humidity sensor; the gas tank (1) is provided with a pressure gauge (15), and the gas storage tank (1) An intake pipe is provided, and an intake valve (16) is arranged on the intake pipe; the vacuum pump is connected to the gas storage tank (1) through a vacuum pumping line, and a vacuum pump intake valve (9) is arranged on the vacuum pumping line.

2. The sulphur hexafluoride on-line hygrometer calibration device according to claim 1, wherein: the gas storage tank (1) is provided with a safety valve (10).

3. The sulphur hexafluoride on-line hygrometer calibration device according to claim 1 or 2, wherein: the pressure gauge (15) and the circulating pressure gauge (11) are vacuum positive pressure dual-purpose pressure gauges. The gas tank

(1), vacuum pump (2), calibration chamber (3) and circulation pump compartment (4) are all mounted on the movable frame.

4. A method for verifying a sulphur hexafluoride on-line hygrometer calibration apparatus according to claim 1, wherein:

a) System drying:

Close the contact valve (7), exhaust valve (8), intake valve (16), open check inlet pot (5), outlet valve (6) and vacuum pump intake valve (9), start diaphragm pump (13) And vacuum pump (2), pumping to the circulating pressure gauge (11) and pressure gauge (15) indication - 0. 08MPa, stop the vacuum pump, close the vacuum pump intake valve (9), inject dry nitrogen from the intake valve (16) The circulating pressure gauge (11) and the pressure gauge (15) indicate 1. 2 MPa; by opening the contact valve (7) and the exhaust valve (8), the pressure is reduced to 0.12 MPa, and the intake valve (16) is closed; , Close the vacuum pump intake valve (9) after the system is dry.

b) Static gas distribution:

By calculation, the injection of water vapor from the intake valve (16) and drying of the nitrogen gas into the tank to achieve the required pressure;

c) Calibration:

After the gas circulation in the system is 5 minutes, open the contact valve (7) and the exhaust valve (8), deflate at 0. 2L/min for 2 minutes, and then take a sample from the exhaust flow meter (14) outlet to detect the inside of the gas tank. Gas moisture Profit request

d) Check:

Close the check inlet valve (5) and the outlet valve (6), open the contact valve (7), release the pressure from the check chamber and the circulating pump chamber from the exhaust valve (8), unload the check chamber interface, and connect the school. Humidity sensor;

Open the check inlet valve (5), clean the check chamber and the circulating pump chamber at 0. 5L/min for 5 minutes, open the outlet valve (6), close the contact valve (7) and the exhaust valve (8), cycle 2 Minute

Open the contact valve (7), close the check inlet valve (5) and the outlet valve (6), open the exhaust valve (8) to reduce the pressure of the check chamber and the circulating pump chamber to the working pressure of the humidity sensor, and verify the humidity sensor. Pressure from high to low, multi-pressure point calibration of the same humidity sensor;

Adjust the humidity of the gas in the gas tank by using dry nitrogen, repeat the calibration and calibration process, and complete the verification of different humidity;

Repeat the above process after replacing the sensor;