Platform and method for detecting performance of insulating liquid

Abstract

The invention discloses a platform and method for detecting the performance of insulating liquid, and relates to the technical field of liquid insulation level monitoring of high-voltage equipment. Comprising a test module which comprises a platform, a test box, a first electrode and a second electrode, the test box is arranged on the platform, an injection port is formed in the test box, an isolation box is arranged above the test box, through holes are formed in the test box and the isolation box, the second electrode is arranged in the test box, one end of the first electrode enters the test box from the isolation box through the through hole, and the other end of the first electrode enters the test box from the isolation box; the first electrode is slidably connected with the isolation box, and the first electrode and the second electrode are connected with an external power supply through a first circuit and a second circuit respectively; the monitoring module comprises an oscilloscope, the first circuit is connected with a third circuit, one end, far away from the first circuit, of the third circuit is connected with the second circuit, and the third circuit is connected with the oscilloscope. According to the platform for detecting the performance of the insulating liquid, the performance of the insulating liquid can be accurately tested, and the testing efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid insulation level monitoring of high-voltage equipment, and more particularly to a platform and method for detecting the performance of insulating liquid. Background Art

[0002] In power systems and high-voltage equipment, insulating liquids (such as transformer oil, insulating oil, etc.) are widely used in transformers, cables, high-voltage switches and other equipment to provide insulation and cooling functions. The insulation performance and thermal stability of insulating liquids directly affect the operating reliability and service life of power equipment. Therefore, a comprehensive evaluation of the insulation performance of insulating liquids, especially the partial discharge (PD) and DC breakdown strength (DC Breakdown Strength) tests, is of great significance to ensure the safe operation of power equipment.

[0003] Partial discharge refers to the electrical discharge phenomenon in certain areas of the insulation system. This discharge will not completely break down the insulation, but will partially damage the insulation material. The occurrence of partial discharge is usually due to defects such as bubbles, impurities or uneven structure in the insulation material. Over time, it may cause aging and decomposition of the insulation material, and even cause complete failure of the equipment. Especially under the action of long-term electric fields, partial discharge will accelerate the degradation of the insulation material and eventually lead to the breakdown of the insulation system. Therefore, the evaluation of partial discharge characteristics is particularly important in the testing of insulating liquids.

[0004] DC breakdown strength is an important indicator to measure the ability of insulating liquid to resist breakdown under the action of DC voltage. The DC breakdown strength of insulating liquid is closely related to multiple factors such as its internal chemical composition, purity, temperature, pressure, etc. Under normal circumstances, insulating liquid should have a higher breakdown voltage to ensure that breakdown failure does not occur under high voltage. However, during long-term operation, insulating liquid may be affected by contaminants such as moisture, bubbles, and solid impurities, resulting in a decrease in its breakdown strength. Therefore, regular detection and evaluation of the DC breakdown strength of insulating liquid is of great significance for preventing power equipment failures.

[0005] With the continuous upgrading of power systems and the increasing requirements for the reliability of high-voltage equipment, partial discharge and DC breakdown strength test technologies will develop towards higher accuracy, stronger adaptability, higher test efficiency, etc. Therefore, how to build a device with simple structure, easy disassembly, higher test efficiency, more flexible and controllable test conditions, and lower maintenance cost, to provide more complete technical guarantees for the safe operation of power systems and high-voltage equipment, provide key technical support for the preventive maintenance of power equipment, and promote the standardization process of insulating liquid performance evaluation is an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0006] In view of this, the present invention provides a platform and method for detecting the performance of insulating liquid, which can accurately test the performance of insulating liquid and improve the test efficiency. In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides a platform for detecting the performance of an insulating liquid, comprising:

[0008] A test module, comprising a platform, a test box, a first electrode and a second electrode, wherein the test box is arranged on the platform, an injection port is arranged on the test box, an isolation box is arranged above the test box, through holes are arranged on the test box and the isolation box, the second electrode is arranged in the test box, one end of the first electrode enters the test box from the isolation box through the through hole, the first electrode is connected to the isolation box, and the first electrode and the second electrode are connected to an external power supply through a first circuit and a second circuit respectively, so that a uniform electric field is formed between the first electrode and the second electrode;

[0009] The monitoring module comprises an oscilloscope, the first circuit is connected to a third circuit, one end of the third circuit away from the first circuit is connected to the second circuit, and the third circuit is connected to the oscilloscope.

[0010] Furthermore, a digital signal generator and a signal amplifier are connected in series at one end of the first circuit close to the external power supply. The signal amplifier is arranged at the output end of the digital signal generator, and the conversion between direct current and alternating current in the first circuit is realized through the digital signal generator.

[0011] Furthermore, a connecting ring is provided at the connection between the first circuit and the third circuit, and a wiring protection box is provided on the outer cover of the connecting ring.

[0012] Furthermore, a first protection resistor is also provided on the third circuit, the output end of the first protection resistor is connected to the input end of the oscilloscope, a fourth circuit is connected between the output end of the first protection resistor and the output end of the oscilloscope, and a sampling resistor is connected to the fourth circuit.

[0013] Furthermore, it also includes a container cleaning box, and the container cleaning box is arranged on the platform.

[0014] Furthermore, the first electrode is an electrode needle, and the second electrode is an electrode plate.

[0015] Furthermore, a thread is provided at one end of the electrode needle close to the isolation box, and a nut is externally connected to the electrode needle.

[0016] In another aspect, the present invention provides a method for detecting the performance of an insulating liquid, wherein the method uses the above-mentioned platform for detecting the performance of an insulating liquid, and comprises the following steps:

[0017] S10: Place the first electrode through the through hole from the isolation box into the test box, and inject synthetic ester oil along the inner wall of the test box through the injection port until the insulating liquid submerges the bottom of the first electrode by 1.5 cm;

[0018] S20: introducing the phenyl vinyl silicone resin into the isolation box along the inner wall of the isolation box until the top of the first electrode is immersed;

[0019] S30: Let it stand for a while until all liquid surfaces are calm and no bubbles emerge, then turn on the power supply, monitor the partial discharge output signal through an oscilloscope, test it multiple times and take the average value;

[0020] S40: disconnect the power supply, remove the first electrode, and discharge the synthetic ester oil in the test box and the phenyl vinyl silicone resin in the isolation box;

[0021] S50: Place the first electrode through the through hole from the isolation box into the test box, and inject the same synthetic ester oil that has been oxidized and contaminated along the inner wall of the test box through the injection port until the insulating liquid submerges the bottom of the first electrode by 1.5 cm, and repeat S20-S30.

[0022] In another aspect, the present invention provides a method for detecting the performance of an insulating liquid, wherein the method uses the above-mentioned platform for detecting the performance of an insulating liquid, and comprises the following steps:

[0023] S100: Place the first electrode through the through hole from the isolation box into the test box, and inject synthetic ester oil along the inner wall of the test box through the injection port until the insulating liquid submerges the bottom of the first electrode by 1.5 cm;

[0024] S200: introducing phenyl vinyl silicone resin into the isolation box along the inner wall of the isolation box until the top of the first electrode is immersed;

[0025] S300: Let it stand for a while until all liquid surfaces are calm and no bubbles emerge, then turn on the power, adjust the output current of the digital generator to DC, adjust the output signal of the signal amplifier to 12.625 kV, and monitor the breakdown voltage through an oscilloscope;

[0026] S400: disconnect the power supply, remove the first electrode, and discharge the synthetic ester oil in the test box and the phenyl vinyl silicone resin in the isolation box;

[0027] S500: Place the first electrode through the through hole from the isolation box into the test box, and inject synthetic ester oil with another oil gap width through the injection port along the inner wall of the test box until the insulating liquid submerges the bottom of the first electrode by 1.5 cm;

[0028] S600: Repeat S200-S500 to complete the DC breakdown level test of synthetic ester oil with different oil gap widths.

[0029] It can be seen from the above technical solution that, compared with the prior art, the present invention discloses a platform for detecting the performance of insulating liquids, which connects an external power supply through a first electrode and a second electrode, performs a partial discharge test on the insulating liquid to be tested, detects the partial discharge signal through an oscilloscope, and detects the partial discharge level of the insulating liquid to be tested, thereby completing a rapid detection of the partial discharge level of the liquid to be tested. The isolation box prevents the test process from being polluted and interfered by the outside, thereby ensuring the accuracy of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0031] Figure 1 A schematic diagram of the structure of a platform for detecting the performance of insulating liquid provided by the present invention;

[0032] Figure 2 A schematic diagram of the internal structure of the test box provided by the present invention;

[0033] Figure 3 A schematic diagram of the structure of an electrode needle is provided for the present invention;

[0034] Figure 4 A schematic diagram of the structure of the wiring protection box provided by the present invention;

[0035] Figure 5 A partial discharge level diagram of different states of the insulating liquid provided by the present invention;

[0036] Figure 6 The invention provides the DC breakdown level of the insulating liquid at different oil gap widths.

[0037] In the figure: 1, second circuit; 2, container cleaning box; 3, injection port; 4, test box; 5, isolation box; 6, wiring protection box; 7, first circuit; 8, signal amplifier; 9, digital signal generator; 10, third circuit; 11, first protection resistor; 12, sampling resistor; 13, fourth circuit; 14, oscilloscope; 15, first electrode; 16, second electrode; 17, nut; 18, connecting ring; 19, second protection resistor. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] See also Figure 1-6 On the one hand, an embodiment of the present invention discloses a platform for detecting the performance of insulating liquid, comprising:

[0040] The test module includes a platform, a test box 4, a first electrode 15 and a second electrode 16. The test box 4 is arranged on the platform, an injection port 3 is arranged on the test box 4, an isolation box 5 is arranged above the test box 4, and through holes are arranged on the test box 4 and the isolation box 5. The second electrode 16 is arranged in the test box 4, one end of the first electrode 15 enters the test box 4 from the isolation box 5 through the through hole, the first electrode 15 is connected to the isolation box 5, and the first electrode 15 and the second electrode 16 are respectively connected to an external power supply through a first circuit 7 and a second circuit 1, so that a uniform electric field is formed between the first electrode 15 and the second electrode 16;

[0041] The monitoring module includes an oscilloscope 14 . The first circuit 7 is connected to a third circuit 10 . One end of the third circuit 10 away from the first circuit 7 is connected to the second circuit 1 . The third circuit 10 is connected to the oscilloscope 14 .

[0042] Insert one end of the first electrode 15 into the test box 4, pour the liquid to be tested into the test box 4 through the injection port 3 until the liquid to be tested immerses the end of the first electrode 15 close to the second electrode 16, connect the power supply, the first circuit 7, the second circuit 1 and the third circuit 10, so that the power supply supplies power to the first electrode 15, the second electrode 16 and the oscilloscope 14, pass alternating current into the circuit, pour the insulating liquid with insulation, high temperature resistance and corrosion resistance into the isolation box 5, so that the insulating liquid to be tested in the test box 4 will not be disturbed by the outside world during the test process, and display the partial discharge signal of the insulating liquid to be tested through the oscilloscope 14 to obtain the partial discharge level of the insulating liquid to be tested.

[0043] After completing the partial discharge level test of the insulating liquid to be tested, the power supply is disconnected, the insulating liquid to be tested in the test box 4 is poured out, the isolation liquid in the isolation box 5 is poured out, and the contaminated insulating liquid to be tested is re-injected into the test box 4, and partial discharge detection is performed on the contaminated insulating liquid to be tested to obtain the partial discharge levels of the insulating liquid to be tested in different states, thereby realizing efficient detection of the partial discharge levels of the insulating liquid to be tested in different states.

[0044] In some embodiments, a digital signal generator 9 and a signal amplifier 8 are connected in series at one end of the first circuit 7 close to the external power supply. The signal amplifier 8 is arranged at the output end of the digital signal generator 9, and the conversion between direct current and alternating current in the first circuit 7 is realized through the digital signal generator 9.

[0045] The digital signal generator 9 converts the alternating current output by the power supply into direct current, thereby realizing the conversion between alternating current and direct current, and passing direct current into the circuit, so that the platform can test the direct current breakdown level of the insulating liquid to be tested.

[0046] The current output by the digital signal generator 9 is amplified by the signal amplifier 8 to improve the signal-to-noise ratio of the output signal.

[0047] When testing the DC breakdown level of the insulating liquid to be tested, the insulating liquid to be tested is poured into the test box 4 through the injection port 3 until the liquid to be tested immerses the end of the first electrode 15 close to the second electrode 16, and the power supply, the first circuit 7, the second circuit 1 and the third circuit 10 are connected. The AC power output by the power supply is converted into DC power by the digital signal generator 9 and the first electrode 15, the second electrode 16 and the oscilloscope 14 are powered. The isolation liquid is poured into the isolation box 5, and the breakdown voltage of the insulating liquid to be tested is displayed by the oscilloscope 14 to obtain the DC breakdown level of the insulating liquid to be tested.

[0048] The insulating liquid to be tested is replaced, and a plurality of insulating liquids to be tested with different oil gap widths are sequentially injected into the test box 4 for testing to obtain the influence of the oil gap width on the DC breakdown level of the insulating liquid to be tested.

[0049] In some embodiments, a connection ring 18 is provided at the connection between the first circuit 7 and the third circuit 10 , and a wiring protection box 6 is provided outside the connection ring 18 .

[0050] The connection between the first circuit 7 and the third circuit 10 is achieved via a connecting ring 18 .

[0051] In some embodiments, a first protection resistor 11 is further provided on the third circuit 10, the output end of the first protection resistor 11 is connected to the input end of the oscilloscope 14, a fourth circuit 13 is connected between the output end of the first protection resistor 11 and the output end of the oscilloscope 14, and a sampling resistor 12 is connected to the fourth circuit 13.

[0052] The oscilloscope 14 is protected by the first protection resistor 11 and the sampling resistor 12 to ensure the accuracy of the test result.

[0053] In some embodiments, a second protection resistor 19 is disposed at one end of the second circuit close to the power supply, the sampling resistor 12 is 1 MΩ, the first protection resistor 11 is 500 MΩ, and the second protection resistor 19 is 30 MΩ.

[0054] In some embodiments, a container cleaning box 2 is further included, and the container cleaning box 2 is disposed on the platform.

[0055] In some embodiments, the first electrode 15 is an electrode needle, and the second electrode 16 is an electrode plate.

[0056] After completing the test of the partial discharge level or DC breakdown level of the insulating liquid to be tested, the electrode needle and the electrode plate are placed in the container cleaning box 2 to complete the cleaning of the electrode needle and the electrode plate to prevent residual liquid from affecting the next detection.

[0057] In some embodiments, a thread is provided at one end of the electrode needle close to the isolation box 5 , and a nut 17 is connected to the outside of the electrode needle.

[0058] In some embodiments, the nut 17 is connected to the isolation box 5, and a scale value is set on the electrode needle. By changing the position of the threaded connection between the electrode needle and the nut 17, the depth of the electrode needle entering the test box 4 is changed, and the distance between the electrode needle and the electrode plate is changed.

[0059] When testing the insulating liquid to be tested, adjust the distance between the electrode needle and the electrode plate to ensure the accuracy of the test results.

[0060] On the other hand, an embodiment of the present invention discloses a method for detecting the performance of an insulating liquid. The method uses the above-mentioned platform for detecting the performance of an insulating liquid to complete the detection of the partial discharge level of the insulating liquid, including the following steps:

[0061] S10: Place the first electrode 15 through the through hole from the isolation box 5 into the test box 4, and inject the synthetic ester oil through the injection port 3 along the inner wall of the test box 4 until the insulating liquid submerges the bottom of the first electrode 15 by 1.5 cm;

[0062] S20: introducing the phenyl vinyl silicone resin into the isolation box 5 along the inner wall of the isolation box 5 until the top of the first electrode 15 is immersed;

[0063] S30: Let the liquid stand for a while until all liquid surfaces are calm and no bubbles emerge, then turn on the power supply, pass AC current into the circuit, monitor the partial discharge output signal through the oscilloscope 14, and perform multiple tests to obtain the average value;

[0064] S40: disconnect the power supply, remove the first electrode 15, and discharge the synthetic ester oil in the test box 4 and the phenyl vinyl silicone resin in the isolation box 5;

[0065] S50: Place the first electrode 15 through the through hole from the isolation box 5 into the test box 4, and inject the same synthetic ester oil that has been oxidized and contaminated along the inner wall of the test box 4 through the injection port 3 until the insulating liquid submerges the bottom of the first electrode 15 by 1.5 cm, and repeat S20-S30.

[0066] On the other hand, a method for detecting the performance of an insulating liquid is provided. The method uses the above-mentioned platform for detecting the performance of an insulating liquid to complete the detection of the DC breakdown level of the insulating liquid, comprising the following steps:

[0067] S100: The first electrode 15 is placed through the through hole from the isolation box 5 into the test box 4, and synthetic ester oil is injected along the inner wall of the test box 4 through the injection port 3 until the insulating liquid submerges the bottom of the first electrode 15 by 1.5 cm;

[0068] S200: introducing phenyl vinyl silicone resin into the isolation box 5 along the inner wall of the isolation box 5 until the top of the first electrode 15 is immersed;

[0069] S300: Let it stand for a while until all liquid surfaces are calm and no bubbles emerge, turn on the power supply, adjust the output current of the digital generator to direct current, adjust the output signal of the signal amplifier to 12.625 kV, and monitor the breakdown voltage through the oscilloscope 14;

[0070] S400: disconnect the power supply, remove the first electrode 15, and discharge the synthetic ester oil in the test box 4 and the phenyl vinyl silicone resin in the isolation box 5;

[0071] S500: The first electrode 15 is placed through the through hole from the isolation box 5 into the test box 4, and synthetic ester oil with another oil gap width is injected through the injection port 3 along the inner wall of the test box 4 until the insulating liquid submerges the bottom end of the first electrode 15 by 1.5 cm;

[0072] S600: Repeat S200-S500 to complete the DC breakdown level test of synthetic ester oil with different oil gap widths;

[0073] S700: Replace the insulating liquid to be tested with natural ester oil, repeat S100-S600, and complete the DC breakdown level test of natural ester oil with different oil gap widths;

[0074] S800: Replace the insulating liquid to be tested with mineral oil, repeat S100-S600, and complete the DC breakdown level test of mineral oil with different oil gap widths.

[0075] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0076] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A platform for detecting the performance of insulating liquid, characterized in that: include: A test module, comprising a platform, a test box, a first electrode and a second electrode, wherein the test box is arranged on the platform, an injection port is arranged on the test box, an isolation box is arranged above the test box, through holes are arranged on the test box and the isolation box, the second electrode is arranged in the test box, one end of the first electrode enters the test box from the isolation box through the through hole, the first electrode is connected to the isolation box, and the first electrode and the second electrode are connected to an external power supply through a first circuit and a second circuit respectively, so that a uniform electric field is formed between the first electrode and the second electrode; The monitoring module comprises an oscilloscope, the first circuit is connected to a third circuit, one end of the third circuit away from the first circuit is connected to the second circuit, and the third circuit is connected to the oscilloscope.

2. The platform for detecting the properties of insulating liquid according to claim 1, characterized in that: A digital signal generator and a signal amplifier are connected in series at one end of the first circuit close to the external power supply. The signal amplifier is arranged at the output end of the digital signal generator. The conversion between direct current and alternating current in the first circuit is realized through the digital signal generator.

3. The platform for detecting the properties of insulating liquid according to claim 1, characterized in that: A connecting ring is provided at the connection between the first circuit and the third circuit, and a wiring protection box is provided on the outer cover of the connecting ring.

4. The platform for detecting the properties of insulating liquid according to claim 1, characterized in that: The third circuit is also provided with a first protection resistor, the output end of the first protection resistor is connected to the input end of the oscilloscope, a fourth circuit is connected between the output end of the first protection resistor and the output end of the oscilloscope, and the fourth circuit is connected with a sampling resistor.

5. The platform for detecting the properties of insulating liquid according to claim 1, characterized in that: It also includes a container cleaning box, which is arranged on the platform.

6. The platform for detecting the properties of insulating liquid according to claim 1, characterized in that: The first electrode is an electrode needle, and the second electrode is an electrode plate.

7. The platform for detecting the properties of insulating liquid according to claim 6, characterized in that: A thread is arranged at one end of the electrode needle close to the isolation box, and a nut is externally connected to the electrode needle.

8. A method for detecting the performance of an insulating liquid, characterized in that: The method uses the platform for detecting the properties of insulating liquid according to any one of claims 1 to 7, comprising the following steps: S10: Place the first electrode through the through hole from the isolation box into the test box, and inject synthetic ester oil along the inner wall of the test box through the injection port until the insulating liquid submerges the bottom of the first electrode by 1.5 cm; S20: introducing the phenyl vinyl silicone resin into the isolation box along the inner wall of the isolation box until the top of the first electrode is immersed; S30: Let it stand for a while until all liquid surfaces are calm and no bubbles emerge, then turn on the power supply, monitor the partial discharge output signal through an oscilloscope, test it multiple times and take the average value; S40: disconnect the power supply, remove the first electrode, and discharge the synthetic ester oil in the test box and the phenyl vinyl silicone resin in the isolation box; S50: Place the first electrode through the through hole from the isolation box into the test box, and inject the same synthetic ester oil that has been oxidized and contaminated along the inner wall of the test box through the injection port until the insulating liquid submerges the bottom of the first electrode by 1.5 cm, and repeat S20-S30.

9. A method for detecting the performance of an insulating liquid, characterized in that: The method uses the platform for detecting the properties of insulating liquid according to claim 2, and comprises the following steps: S100: Place the first electrode through the through hole from the isolation box into the test box, and inject synthetic ester oil along the inner wall of the test box through the injection port until the insulating liquid submerges the bottom of the first electrode by 1.5 cm; S200: introducing phenyl vinyl silicone resin into the isolation box along the inner wall of the isolation box until the top of the first electrode is immersed; S300: Let it stand for a while until all liquid surfaces are calm and no bubbles emerge, then turn on the power, adjust the output current of the digital generator to DC, adjust the output signal of the signal amplifier to 12.625 kV, and monitor the breakdown voltage through an oscilloscope; S400: disconnect the power supply, remove the first electrode, and discharge the synthetic ester oil in the test box and the phenyl vinyl silicone resin in the isolation box; S500: Place the first electrode through the through hole from the isolation box into the test box, and inject synthetic ester oil with another oil gap width through the injection port along the inner wall of the test box until the insulating liquid submerges the bottom of the first electrode by 1.5 cm; S600: Repeat S200-S500 to complete the DC breakdown level test of synthetic ester oil with different oil gap widths.

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