Device and method for detecting gas production performance of insulating oil under electric field ionization

Abstract

The invention discloses a device for detecting gas production performance of insulating oil under electric field ionization, the device comprises a host unit and a vacuum unit, the host unit comprises a controller, a high voltage power supply, a constant temperature bath and a three-way pipeline, data processing software is preset in the controller of the host unit, and the controller is externally configured with an operation panel; an electrode cup body is arranged in the constant-temperature bath, the constant-temperature bath is communicated with the vacuum unit through a three-way pipeline, and the host unit is in signal connection with a vacuum pump in the vacuum unit. The invention further discloses a method for detecting the gas production performance of the insulating oil under electric field ionization. According to the equipment and the method disclosed by the invention, the insulating oil in the detection equipment is subjected to vacuum degassing, so that the gas content in the oil meets the actual working condition, and the influence of the gas production rate of the to-be-detected oil sample on the system pressure under the partial discharge can be reflected by adopting a pressure monitoring technology.

Description

Technical Field

[0001] The invention belongs to the technical field of power transmission and transformation of power grids, and relates to a device for detecting gas production performance of insulating oil under electric field ionization. The invention also relates to a method for detecting gas production performance of insulating oil under electric field ionization. Background Art

[0002] With the rapid development of the power transmission and transformation industry, as well as the rapid construction of 1000kV UHV AC transmission projects and ±800kV UHV DC transmission projects, high-voltage and ultra-high-voltage bushings are important components of power transformers, and high-voltage transformers are important measuring equipment for power transmission systems. Due to their compact structure, small size, and low oil consumption, such equipment will produce a large amount of gas when local overheating or partial discharge occurs in the equipment. If these gases cannot be absorbed by the oil in time, they will pose a great threat to the safe operation of the equipment. Therefore, such equipment has extremely strict requirements on the gas production performance of the oil in the electric field. The gas production performance of transformer oil under the electric field determines the gas content in the transformer oil, which is a key factor in the safe operation of the transformer. Therefore, it is very important to evaluate the gas production performance of transformer oil under high-voltage electric fields to optimize the composition of transformer oil and improve its anti-gassing performance.

[0003] At present, the testing equipment and methods for the gas generation performance of transformer oil under electric field mainly include GB / T11142, ASTM D2300 and IEC60628. The principle of these existing methods is to evaluate the performance of transformer oil gas generation under electric field ionization, and to measure the effect of radial electric field and temperature field after transformer oil is saturated with hydrogen, and the tendency of oil itself to absorb or release gas due to discharge reaction at the oil-hydrogen interface under the conditions of voltage of 10kV, oil temperature of 80℃ and test time of 60min or 120min. The main defects of these methods are that they can withstand low electric field strength and cannot simulate the problem of gas generation of insulating oil under high electric field strength in mutual inductors and transformer bushings; second, the existing detection methods all use hydrogen or nitrogen to detect the gas evolution of insulating oil, which is inconsistent with the actual working conditions that the insulating oil in power equipment is vacuum degassed, resulting in a very low nitrogen content in the oil and basically no hydrogen; third, vacuum oil filling cannot be achieved during the injection process of the oil sample to be tested. The amount of gas in the oil will directly affect the starting voltage of the oil partial discharge, and then affect the accurate measurement of the gas content in the oil, thereby affecting the correct judgment of the electric field strength on the gas production trend in the oil. Summary of the invention

[0004] The purpose of the present invention is to provide a detection device for the gas production performance of insulating oil under electric field ionization, which solves the problem in the prior art that it is difficult to accurately measure the gas content in the oil, thereby affecting the correct judgment of the gas production trend in the oil by the electric field strength.

[0005] Another object of the present invention is to provide a method for detecting the gas generation performance of insulating oil under electric field ionization.

[0006] The technical solution adopted by the present invention is a detection device for the gas production performance of insulating oil under electric field ionization, including a main unit and a vacuum unit. The main unit includes a controller, a high-voltage power supply, a constant temperature bath and a three-way pipeline. The controller of the main unit is pre-installed with data processing software, and the controller is externally configured with an operation panel; an electrode cup body is arranged inside the constant temperature bath, and the constant temperature bath is connected to the vacuum unit through a three-way pipeline, and the main unit is also connected to the vacuum pump signal in the vacuum unit.

[0007] Another technical solution adopted by the present invention is a method for detecting the gas generation performance of insulating oil under electric field ionization, which is implemented by using the above-mentioned detection equipment for the gas generation performance of insulating oil under electric field ionization according to the following steps:

[0008] Step 1: Pre-process and obtain the oil sample to be tested.

[0009] Take an appropriate amount of transformer oil to be tested, filter it with a fiber membrane with a pore size of 2 to 5 μm, and dehydrate the filtered transformer oil under a vacuum degree of 0.1333 to 1.333 KPa until the moisture content of the transformer oil after dehydration is less than 10 mg / kg and the particle contamination of 5 μm is less than 1000 particles / 100 mL, thereby obtaining an oil sample to be tested that meets the requirements of symbol detection;

[0010] Step 2: Assemble the electrode cup.

[0011] First, clean each component in the electrode cup separately and dry it thoroughly; pour an appropriate amount of the oil sample to be tested into the high vacuum glass cup, and then assemble the electrode cup according to the above structure;

[0012] Step 3: Connect all equipment and pipelines.

[0013] Place the electrode cup containing the oil sample to be tested in the constant temperature bath of the host unit, connect the gas outlet of the electrode cup to the vacuum pump and the pressure sensor through a three-way pipeline, and connect the high-voltage electrode to the high-voltage power supply;

[0014] Step 4: Set relevant control and detection parameters.

[0015] On the operation panel of the host unit, set various detection parameters, including detection temperature, vacuum degree of the electrode cup, voltage value of the high-voltage power supply, and acquisition cycle, and start detection;

[0016] Step 5: Collect data during the test and obtain test results

[0017] During the detection process, the vacuum degree in the electrode cup and the corresponding time are regularly collected and recorded. The difference in vacuum degree before and after the detection is divided by the collection period as the output result to complete the detection.

[0018] The beneficial effect of the present invention is that it simulates the gas generation phenomenon of insulating oil under high electric field strength in mutual inductors and transformer bushings. The insulating oil in the detection equipment is vacuum degassed so that the gas content in the oil meets the actual working conditions. By adopting pressure monitoring technology, it can better reflect the influence of the gas production of the oil sample to be tested under local release on the system pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structural principle of the device of the present invention;

[0020] Figure 2 It is a schematic diagram of the structure of the electrode cup body in the device of the present invention;

[0021] Figure 3 It is a structural schematic diagram of the three-way pipeline in the equipment of the present invention.

[0022] In the figure, 1. main unit, 2. high voltage power supply, 3. constant temperature bath, 4. electrode cup, 5. vacuum unit, 6. high voltage electrode, 7. high voltage bushing, 8. high vacuum glass cup, 9. low voltage electrode, 10. electrode fixing ring, 11. low voltage bushing, 12. three-way valve, 13. solenoid valve I, 14. solenoid valve II, 15. pressure sensor. DETAILED DESCRIPTION

[0023] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Reference Figure 1 The structure of the detection device of the present invention is that it includes a host unit 1 and a vacuum unit 5. The host unit 1 includes a controller, a high-voltage power supply 2, a constant temperature bath 3 and a three-way pipeline. The controller of the host unit 1 is pre-installed with data processing software, and the controller is externally configured with an operation panel; an electrode cup body 4 is arranged inside the constant temperature bath 3, and the constant temperature bath 3 is connected to the vacuum unit 5 through a three-way pipeline. The host unit 1 is also connected to the vacuum pump signal in the vacuum unit 5;

[0025] Reference Figure 2The specific structure of the electrode cup body 4 is that it includes a high vacuum glass cup body 8, the inner edge of the upper end of the high vacuum glass cup body 8 is threadedly sleeved with the high voltage bushing 7, and the contact surface between the upper end surface of the high vacuum glass cup body 8 and the high voltage bushing 7 is provided with a fluororubber sealing ring, the inner edge of the lower end of the high vacuum glass cup body 8 is threadedly sleeved with the low voltage bushing 11, and the contact surface between the lower end surface of the high vacuum glass cup body 8 and the low voltage bushing 11 is provided with another fluororubber sealing ring; a high voltage electrode 6 is passed through the high voltage bushing 7, and the top of the high voltage electrode 6 extends upward from the high voltage bushing 7 In addition, an electrode fixing ring 10 is installed between the outer circumference of the lower end of the high-voltage electrode 6 and the inner circumference of the lower end surface of the high-vacuum glass cup body 8; an annular low-voltage electrode 9 is installed on the lower part of the outer wall of the high-vacuum glass cup body 8, and the lower end of the low-voltage electrode 9 is also connected to the bottom plate of the low-voltage bushing 11, and the low-voltage electrode 9 is connected to the ground wire; the upper end of the high-voltage electrode 6 is connected to the high-voltage power supply 2 to the outside, and the high-vacuum glass cup body 8 is connected to the vacuum pump of the vacuum unit 5 through a three-way pipeline; the above-mentioned high-voltage bushing 7 and low-voltage bushing 11 are both made of insulating materials.

[0026] Reference Figure 3 The structure of the three-way pipeline includes a three-way valve 12, a solenoid valve I13, a solenoid valve II14 and a pressure sensor 15. The air outlet of the high vacuum glass cup body 8 is connected to the direct inlet of the three-way valve 12, and the direct outlet of the three-way valve 12 is connected to the vacuum pump exhaust port of the vacuum unit 5 through the solenoid valve I13; the right-angle outlet of the three-way valve 12 is connected to the pressure sensor 15 through the solenoid valve II14, and the sensor signal of the pressure sensor 15 is connected to the controller of the host unit 1.

[0027] The controller of the host unit 1 is respectively connected to the above-mentioned solenoid valve I13, solenoid valve II14 and pressure sensor 15, high voltage power supply 2, constant temperature bath 3, and vacuum pump signals to collect signals and feedback signals in order to coordinate and control the operating parameters of the connected components.

[0028] The working principle of the detection equipment of the present invention is: at a set temperature, the oil sample to be tested is subjected to vacuum degassing treatment. Under the set vacuum degree, under the action of continuously applied voltage and temperature, the oil sample to be tested releases gas, which will cause the vacuum degree in the electrode cup body 4 to change. By detecting the vacuum degree change value in the electrode cup body 4, the gas production of the oil sample to be tested is calculated.

[0029] The installation and testing process of the detection equipment of the present invention is: first, the lower end of the high vacuum glass cup body 8 is firmly mounted on the low-pressure bushing 11, and an appropriate amount of the oil sample to be tested is poured from the upper end of the high vacuum glass cup body 8, and the oil sample to be tested is located in the inner cavity of the high vacuum glass cup body 8; then, the high-voltage bushing 7 is mounted on the upper end of the high vacuum glass cup body 8 filled with the oil sample to be tested, and then the high-voltage electrode 6 is extended from top to bottom into the oil sample to be tested to ensure that there is no air leakage or liquid leakage, and the electrode cup body 4 is assembled; secondly, the assembled electrode cup body 4 is placed in the constant temperature bath 3 of the main machine part, and the air outlet of the high vacuum glass cup body 8 is connected through the three-way pipe. The main unit 1 is connected to the vacuum pump of the vacuum unit 5 through the high-voltage line, the pressure sensor 15 is connected to the controller, and the high-voltage electrode 6 is connected to the high-voltage power supply 2 through the high-voltage line; finally, the detection starts, the main unit 1 controls the vacuum pump of the vacuum unit 5 through the control system and the data line, evacuates the electrode cup 4 to reduce the gas content in the oil sample to be tested and monitors the vacuum degree inside the electrode cup 4, at the same time, controls the temperature inside the constant temperature bath 3 to rise to a predetermined temperature through the data line, controls the high-voltage power supply 2 to output a predetermined voltage to the electrode cup 4 through the data line, and continuously monitors the vacuum degree in the electrode cup 4 until the predetermined time ends.

[0030] The method for detecting the gas generation performance of insulating oil under electric field ionization of the present invention is based on the above-mentioned detection equipment and detection principle and is implemented according to the following steps:

[0031] Step 1: Pre-process and obtain the oil sample to be tested.

[0032] Take an appropriate amount of transformer oil to be tested, filter it with a fiber membrane with a pore size of 2 to 5 μm, and dehydrate the filtered transformer oil under a vacuum degree of 0.1333 to 1.333 kPa until the moisture content of the transformer oil after dehydration is less than 10 mg / kg and the particle contamination of 5 μm is less than 1000 particles / 100 mL, thereby obtaining an oil sample to be tested that meets the requirements of symbol detection;

[0033] Step 2: Assemble the electrode cup 4.

[0034] First, clean each component in the electrode cup 4 separately and dry thoroughly; pour an appropriate amount of the oil sample to be tested into the high vacuum glass cup 8, and then assemble the electrode cup 4 according to the above structure;

[0035] Step 3: Connect all equipment and pipelines.

[0036] Place the electrode cup 4 containing the oil sample to be tested in the constant temperature bath 3 of the host unit 1, connect the gas outlet of the electrode cup 4 to the vacuum pump and the pressure sensor 15 through a three-way pipeline, and connect the high-voltage electrode 6 to the high-voltage power supply 2.

[0037] Step 4: Set relevant control and detection parameters.

[0038] On the operation panel of the host unit 1, set various detection parameters (including detection temperature, vacuum degree of the electrode cup 4, voltage value of the high-voltage power supply, and acquisition cycle), and start detection;

[0039] Step 5: Collect data during the test and obtain the test results.

[0040] During the detection process, the vacuum degree in the electrode cup 4 and the corresponding time are regularly collected and recorded, and the difference in vacuum degree before and after the detection is divided by the collection period (time) as the output result to complete the detection.

[0041] Example 1

[0042] This embodiment 1 uses the aforementioned detection equipment and the aforementioned detection method process to measure the gas generation performance of a transformer oil under electric field ionization conditions, and is implemented according to the following steps:

[0043] Step 1, measuring 500ml transformer oil, adopting pore size to be 5μm fiber membrane to filter, the transformer oil after filtering is dehydrated under vacuum degree of 1.333kPa, the moisture content of transformer oil after dehydration is less than 10mg / kg, and the particle contamination degree of 5μm is less than 1000 / 100mL, and the oil sample to be tested that meets the requirements is obtained;

[0044] Step 2: First, clean and dry the various components of the electrode cup 4, fill 100 ml of the processed oil sample to be tested into the high vacuum glass cup 8, and then assemble the electrode cup 4;

[0045] Step 3: Place the assembled electrode cup 4 in the constant temperature bath 3; the gas outlet of the electrode cup 4 is connected to the vacuum pump and the pressure sensor 15 through the three-way valve 12; the high-voltage electrode 6 is connected to the high-voltage power supply 2 through the high-voltage line.

[0046] Step 4: On the operation panel of the host unit 1, set the detection temperature to 40°C, the vacuum degree of the electrode cup 4 to 3.0 kPa, the voltage value of the high-voltage power supply 2 to 10 kV, the collection period to 8 hours, and start detection.

[0047] Step 5: During the test, the vacuum degree of the electrode cup 4 and the corresponding time are collected and recorded regularly, and the difference in vacuum degree before and after the test is divided by the collection period (time) as the measurement result to complete the test. The results are shown in Table 1.

[0048] Example 2

[0049] The implementation process of Example 1 is different in that: Step 4, on the operation panel of the host unit 1, the detection temperature is set to 60°C, the vacuum degree of the electrode cup 4 is set to 3.0 kPa, the voltage value of the high-voltage power supply 2 is set to 7.5 kV, the collection period is set to 4 hours, and the detection is started. The results are shown in Table 1.

[0050] Example 3

[0051] The implementation process of Example 1 is different in that: Step 4, on the operation panel of the host unit 1, the detection temperature is set to 40°C, the vacuum degree of the electrode cup 4 is set to 3.0 kPa, the voltage value of the high-voltage power supply 2 is set to 5 kV, the collection period is set to 8 hours, and the detection is started. The results are shown in Table 1.

[0052] Example 4

[0053] The implementation process of Example 1 is different in that: Step 4, on the operation panel of the host unit 1, set the detection temperature to 80°C, the vacuum degree of the electrode cup 4 to 3.0 kPa, the voltage value of the high-voltage power supply 2 to 10 kV, the collection period to 4 hours, and start detection.

[0054] The test results of the above four embodiments are shown in Table 1 below.

[0055] Table 1. Data table of four embodiments

[0056]

[0057] In summary, the detection equipment and detection method of the present invention can well realize the detection of the gas production performance of insulating oil under electric field ionization, with accurate data and high work efficiency.

Claims

1. A device for detecting the gas production performance of insulating oil under electric field ionization, characterized in that: The invention comprises a host unit (1) and a vacuum unit (5). The host unit (1) comprises a controller, a high-voltage power supply (2), a constant temperature bath (3) and a three-way pipeline. An electrode cup (4) is arranged inside the constant temperature bath (3). The constant temperature bath (3) is connected to the vacuum unit (5) through the three-way pipeline. The host unit (1) is also connected to the vacuum pump signal in the vacuum unit (5).

2. The detection device for the gas generation performance of insulating oil under electric field ionization according to claim 1 is characterized in that: The controller of the host unit (1) is pre-installed with data processing software, and the controller is externally configured with an operation panel.

3. The detection device for the gas generation performance of insulating oil under electric field ionization according to claim 1 is characterized in that: The specific structure of the electrode cup body (4) is that it includes a high vacuum glass cup body (8), the inner edge of the upper end of the high vacuum glass cup body (8) is threadedly sleeved with the high pressure sleeve (7), the contact surface between the upper end surface of the high vacuum glass cup body (8) and the high pressure sleeve (7) is provided with a fluororubber sealing ring, the inner edge of the lower end of the high vacuum glass cup body (8) is threadedly sleeved with the low pressure sleeve (11), the contact surface between the lower end surface of the high vacuum glass cup body (8) and the low pressure sleeve (11) is provided with another fluororubber sealing ring; a high pressure electrode (6) is inserted into the high pressure sleeve (7), and the high pressure electrode (6) is provided with a fluororubber sealing ring. ) extends upward out of the high-voltage bushing (7), and an electrode fixing ring (10) is mounted between the outer circumference of the lower end of the high-voltage electrode (6) and the inner circumference of the lower end surface of the high-vacuum glass cup body (8); an annular low-voltage electrode (9) is mounted on the lower part of the outer wall of the high-vacuum glass cup body (8), and the lower end of the low-voltage electrode (9) is simultaneously connected to the bottom plate of the low-voltage bushing (11), and the low-voltage electrode (9) is connected to the ground wire; the upper end of the high-voltage electrode (6) is connected to the high-voltage power supply (2) facing outward, and the high-vacuum glass cup body (8) is connected to the vacuum pump of the vacuum unit (5) through a three-way pipeline.

4. The device for detecting the gas generation performance of insulating oil under electric field ionization according to claim 3 is characterized in that: The high-voltage bushing (7) and the low-voltage bushing (11) are both made of insulating materials.

5. The detection device for the gas generation performance of insulating oil under electric field ionization according to claim 1 is characterized in that: The structure of the three-way pipeline is that it includes a three-way valve (12), a solenoid valve I (13), a solenoid valve II (14) and a pressure sensor (15); the air outlet of the high vacuum glass cup body (8) is connected to the direct inlet of the three-way valve (12); the direct outlet of the three-way valve (12) is connected to the vacuum pump exhaust port of the vacuum unit (5) through the solenoid valve I (13); the right-angle outlet of the three-way valve (12) is connected to the pressure sensor (15) through the solenoid valve II (14); the sensing signal of the pressure sensor (15) is connected to the controller of the host unit (1).

6. The detection device for the gas generation performance of insulating oil under electric field ionization according to any one of claims 1 or 5, characterized in that: The controller of the host unit (1) is respectively connected to the solenoid valve I (13), solenoid valve II (14), pressure sensor (15), high voltage power supply (2), constant temperature bath (3), and vacuum pump signals to collect signals and feedback signals so as to coordinate and control the operating parameters of the connected components.

7. A method for detecting the gas generation performance of insulating oil under electric field ionization, using the device for detecting the gas generation performance of insulating oil under electric field ionization according to any one of claims 1 to 5, characterized in that: The implementation is carried out according to the following steps: Step 1, pre-processing to obtain the oil sample to be tested; Step 2, assembling the electrode cup body (4); Step 3: Connect all equipment and pipelines; Step 4: Set relevant control and detection parameters; Step 5: Collect data during the test and get the test results. During the detection process, the vacuum degree in the electrode cup body (4) and the corresponding time are regularly collected and recorded, and the difference in vacuum degree before and after the detection is divided by the collection period as the output result to complete the detection.

8. The method for detecting the gas generation performance of insulating oil under electric field ionization according to claim 7, characterized in that: In step 1, the specific process is: Take an appropriate amount of transformer oil to be tested and filter it using a fiber membrane with a pore size of 2 to 5 μm. Dehydrate the filtered transformer oil under a vacuum degree of 0.1333 to 1.333 kPa until the moisture content of the dehydrated transformer oil is less than 10 mg / kg and the particle contamination of 5 μm is less than 1000 particles / 100 mL, thereby obtaining an oil sample to be tested that meets the symbol detection requirements.

9. The method for detecting the gas generation performance of insulating oil under electric field ionization according to claim 7, characterized in that: In step 2 and step 3, the specific process is: Step 2: First, clean each component in the electrode cup body (4) separately and dry them thoroughly; pour an appropriate amount of the oil sample to be tested into the high vacuum glass cup body (8), and then complete the assembly of the electrode cup body (4) according to the above structure; Step 3: Place the electrode cup (4) containing the oil sample to be tested in the constant temperature bath (3) of the host unit (1), connect the gas outlet of the electrode cup (4) to the vacuum pump and the pressure sensor (15) through a three-way pipeline, and connect the high-voltage electrode (6) to the high-voltage power supply (2).

10. The method for detecting the gas generation performance of insulating oil under electric field ionization according to claim 7, characterized in that: In step 4, the specific process is: On the operation panel of the host unit (1), various detection parameters are set, including the detection temperature, the vacuum degree of the electrode cup (4), the voltage value of the high-voltage power supply, and the collection period, and the detection is started.

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