Power cable insulation material detection device and thermo-oxidative aging detection method

Abstract

The invention relates to the technical field of electrical equipment state evaluation, in particular to a power cable insulation material detection device and a thermo-oxidative aging detection method.The power cable insulation material detection device comprises a high-temperature aging oven used for simulating the high-temperature environment where an insulation material is located; the temperature control equipment is used for controlling the temperature in the high-temperature aging box; the oxygen supply equipment is used for supplying oxygen into the high-temperature aging box; the clamp is used for clamping and fixing a detected insulating material sample, clamping the detected sample through the clamp and placing the detected sample in the middle of the high-temperature aging oven, oxygen is supplied to the high-temperature aging oven through the oxygen supply equipment, the temperature in the high-temperature aging oven is controlled through the temperature control equipment, and the temperature in the high-temperature aging oven is controlled through an aging experiment in a short-time high-temperature and oxygen environment. And the aging characteristic of the cable material can be evaluated in a short time.

Description

Technical Field

[0001] The invention relates to the technical field of electrical equipment status assessment, in particular to a power cable insulation material detection device and a thermal oxygen aging detection method. Background Art

[0002] With the increase in electricity demand, the stability and life of power cable materials in various harsh environments have attracted more and more attention. Thermal oxidation aging is one of the main factors affecting the performance and life of cable materials. Existing aging test methods usually take a long time and are difficult to meet the needs of rapid evaluation and research. Therefore, an efficient and reliable short-time thermal oxidation aging sample preparation method is urgently needed to quickly evaluate the aging characteristics of cable materials. To this end, a power cable insulation material detection device and a thermal oxidation aging detection method are proposed. Summary of the invention

[0003] In view of the above problems or problems existing in the prior art, the present invention is proposed.

[0004] Therefore, the object of the present invention is to provide a power cable insulation material detection device and a thermal oxygen aging detection method.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a power cable insulation material detection device, comprising:

[0006] High temperature aging chamber, which is used to simulate the high temperature environment of the insulation material;

[0007] Temperature control equipment, which is used to control the temperature in the high-temperature aging box;

[0008] Oxygen supply equipment, which is used to supply oxygen to the high-temperature aging box;

[0009] A fixture, which is used to clamp and fix the insulating material sample to be tested;

[0010] The aging of insulating materials is simulated by the oxygen supply of the oxygen supply equipment and the high temperature environment provided by the high temperature aging box.

[0011] As a preferred solution of the power cable insulation material detection device of the present invention, it also includes:

[0012] The solenoid valve is arranged between the high temperature aging box and the oxygen supply equipment, and is used to control the flow of oxygen entering the high temperature aging box.

[0013] As a preferred solution of the power cable insulation material detection device of the present invention, it also includes:

[0014] The temperature sensor is arranged in the high temperature aging box and is used to detect the temperature in the high temperature aging box in real time.

[0015] As a preferred solution of the power cable insulation material detection device of the present invention, it also includes:

[0016] The oxygen concentration sensor is arranged in the high temperature aging box and is used for real-time detection of the oxygen concentration in the high temperature aging box.

[0017] As a preferred solution of the power cable insulation material detection device of the present invention, it also includes:

[0018] A hanging rope, which is provided on the clamp and is used to hang the clamp;

[0019] The weighing sensor is arranged in the high-temperature aging box, the suspension rope is connected to the weighing sensor, and the weighing sensor is used to measure the weight of the insulating material sample being tested.

[0020] As a preferred solution of the power cable insulation material detection device of the present invention, it also includes:

[0021] The camera equipment is installed in the high-temperature aging box and is used to observe the state of the sample.

[0022] As a preferred solution of the power cable insulation material detection device of the present invention, the clamp is made of high temperature resistant material.

[0023] The beneficial effects of the power cable insulation material detection device of the present invention are as follows: the sample to be tested is clamped by a clamp and placed in the middle of a high-temperature aging box, oxygen is provided to the high-temperature aging box by an oxygen supply device, and the temperature control device controls the temperature in the high-temperature aging box. Through aging experiments in a short-term high-temperature and oxygen environment, the aging characteristics of the cable material can be evaluated in a relatively short time.

[0024] In order to solve the above technical problems, the present invention also provides the following technical solutions: a method for detecting thermal oxidation aging of power cable insulation materials, comprising:

[0025] Cutting samples from cable material;

[0026] The thermal oxygen aging test is carried out using the power cable insulation material detection device;

[0027] Characterize and analyze samples;

[0028] Conduct tensile test and impact test.

[0029] As a preferred embodiment of the thermal oxidation aging detection method for power cable insulation material of the present invention, the thermal oxidation aging test comprises:

[0030] Place the sample in a high temperature aging box at 149-151°C, keep the oxygen concentration in the box greater than 21%, and conduct a 48-hour aging test;

[0031] The physical properties of the sample are recorded at predetermined time intervals.

[0032] As a preferred solution of the thermal oxidation aging detection method for power cable insulation materials of the present invention, the aged samples are characterized and analyzed using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and infrared spectroscopy (FTIR) techniques.

[0033] The beneficial effects of the thermal oxygen aging detection method for power cable insulation materials of the present invention are as follows: the method can evaluate the aging characteristics of cable materials in a relatively short time through aging experiments in a short-term high temperature and oxygen environment. This is more efficient than the traditional long-term aging test and is suitable for rapid screening and evaluation of material properties; the precise control of the aging box temperature and oxygen flow rate ensures the stability and consistency of the experimental conditions, reduces experimental errors, and improves the repeatability and reliability of the experimental results. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0035] Figure 1 It is a schematic diagram of the overall framework of the power cable insulation material detection device.

[0036] Figure 2 The near infrared spectrum evolution of XLPE sample at 150℃ with aging time. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0038] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0039] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0040] Example 1, reference Figure 1 , which is the first embodiment of the present invention, provides a power cable insulation material detection device, comprising:

[0041] High temperature aging chamber, which is used to simulate the high temperature environment of the insulation material;

[0042] Temperature control equipment, which is used to control the temperature in the high-temperature aging box;

[0043] Oxygen supply equipment, which is used to supply oxygen to the high-temperature aging box;

[0044] A fixture, which is used to clamp and fix the insulating material sample to be tested;

[0045] The aging of insulating materials is simulated by the oxygen supply of the oxygen supply equipment and the high temperature environment provided by the high temperature aging box.

[0046] Specifically, it also includes:

[0047] The solenoid valve is arranged between the high temperature aging box and the oxygen supply equipment to control the flow of oxygen entering the high temperature aging box, thereby ensuring the accuracy of the experimental results.

[0048] Furthermore, it also includes:

[0049] The temperature sensor is installed in the high temperature aging box to detect the temperature in the high temperature aging box in real time, so that the operator can understand the temperature condition in the high temperature aging box in real time.

[0050] Among them, it also includes:

[0051] The oxygen concentration sensor is installed in the high-temperature aging box to detect the oxygen concentration in the high-temperature aging box in real time, so that the operator can understand the oxygen concentration in the high-temperature aging box in real time.

[0052] Preferably, it also includes:

[0053] A hanging rope, which is provided on the clamp and is used to hang the clamp;

[0054] The weighing sensor is arranged in the high temperature aging box, the suspension rope is connected to the weighing sensor, and the weighing sensor is used to measure the weight of the insulating material sample being tested, so that the user can understand the quality change of the material during the experiment.

[0055] It should be noted that it also includes:

[0056] The camera equipment is installed in the high-temperature aging box to observe the state of the sample, so that the operator can observe the morphological changes of the sample during the experiment.

[0057] Preferably, the clamp is made of high temperature resistant material to prevent deformation or release of harmful substances in a high temperature environment.

[0058] When in use, the sample to be tested is clamped by a fixture and placed in the middle of the high-temperature aging box. Oxygen is provided to the high-temperature aging box through an oxygen supply device, and the temperature control device controls the temperature in the high-temperature aging box. Through aging experiments in a short-term high-temperature and oxygen environment, the aging characteristics of the cable material can be evaluated in a relatively short time.

[0059] Example 2, reference Figure 1-2 , which is the second embodiment of the present invention, is different from the previous embodiment in that this embodiment provides a method for detecting thermal oxidation aging of power cable insulation materials, comprising:

[0060] Cut out a sample from the cable material; in this embodiment, select appropriate power cable materials, such as cross-linked polyethylene (XLPE), polypropylene (PP), etc., use isopropyl alcohol to clean the surface of the sample to remove grease and impurities, then rinse with deionized water and dry. Ensure that the surface of the sample is clean to avoid the influence of impurities on the aging process.

[0061] Thermal oxygen aging test was carried out using power cable insulation material testing equipment;

[0062] Thermal oxidative aging tests include:

[0063] Place the sample in a high temperature aging box at 149-151°C, keep the oxygen concentration in the box greater than 21%, and conduct a 48-hour aging test;

[0064] The physical properties of the sample are recorded at predetermined time intervals.

[0065] Specifically, the sample can be placed in a high-temperature aging box at 150°C, and 200 ml of oxygen can be introduced per minute to ensure that the oxygen concentration in the high-temperature aging box is greater than 21%, and an aging experiment can be carried out for 48 hours; the weight change and color change of the sample in different time periods are recorded. It should be noted that the temperature in the high-temperature aging box is kept constant, so that the temperature difference is within 2°C, thereby improving the accuracy of the experiment as much as possible.

[0066] In this embodiment, first, the temperature of the high temperature aging box is set to 150 ° C to ensure that the temperature is uniform and stable. Temperature control is one of the key factors in the aging experiment, and temperature fluctuations may affect the accuracy of the aging results. Secondly, adjust the oxygen flow rate to 200 ml per minute to ensure that there is an appropriate oxygen supply in the aging box. The oxygen concentration should remain constant to simulate the oxidizing conditions in the actual working environment. Finally, the cleaned sample is placed in the sample fixture to ensure that the sample is suspended in the middle position of the aging box to ensure uniform heating.

[0067] The aging time can be adjusted appropriately according to the experimental requirements, but it should be long enough to reflect the aging characteristics. During the aging process, monitor the temperature and oxygen concentration of the aging box every 6 hours to ensure the stability of the experimental conditions. Record the weight change, color change and other physical properties of the sample for subsequent analysis.

[0068] It should be noted that after the aging time is over, carefully remove the sample to avoid additional mechanical stress on the sample. Wear protective gloves when removing to prevent burns from high-temperature samples. Then, place the sample in a clean, dust-free environment to cool to room temperature. During the cooling process, avoid mechanical shock or contact with contaminants. After the sample is cooled, store it in a dry, dark environment to prevent further oxidation and degradation. Samples should be packaged individually to avoid contact and friction with each other.

[0069] Characterize and analyze samples;

[0070] The aged samples were characterized and analyzed using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and infrared spectroscopy (FTIR).

[0071] Conduct tensile test and impact test.

[0072] In this embodiment, mechanical property tests such as tensile tests and impact tests are performed to evaluate the change in mechanical properties of the sample. By testing parameters such as the strength and elastic modulus of the sample, the effect of aging on the mechanical properties of the material can be understood.

[0073] The rest of the structure is the same as that of Example 1.

[0074] Reference Figure 2 , Figure 2 The near infrared spectrum evolution of XLPE sample at 150°C with aging time. According to the experimental steps of the present invention, XLPE sample at 150°C is selected, and the near infrared spectrum (FTIR) test results are as follows: Figure 2As shown. In the figure, two characteristic peaks at 1730nm and 1764nm can be found, which correspond to the first harmonic frequency of the antisymmetric vibration and symmetric vibration of the methylene CH, respectively. As the degree of aging deepens, the absorbance of the two bands decreases. In addition, the 1710nm and 1762nm bands correspond to the short helical molecular chain segments in the amorphous region of XLPE, and the 1730nm and 1765nm bands correspond to the long helical molecular chain segments in the crystalline region of XLPE. From the evolution results in the figure, it can be seen that as the degree of aging deepens, the absorbance of the characteristic peak corresponding to the crystalline region gradually decreases, and the absorbance of the characteristic peak in the amorphous region gradually increases. This phenomenon indicates that as the aging proceeds, the molecular chain in the crystalline region breaks during the thermal oxidative aging process and enters the amorphous region, and a transition from the crystalline region to the amorphous region occurs. During the thermal aging process, the gradual degradation of the aggregated structure and performance of XLPE insulation is mainly caused by the thermal oxidative degradation caused by the oxidation reaction, and the auto-oxidation reaction is the main feature of the thermal oxidative degradation of polymers and the core of thermal oxidative degradation.

[0075] In summary, this method can evaluate the aging characteristics of cable materials in a relatively short time through aging experiments in a short-term high temperature and oxygen environment. This is more efficient than traditional long-term aging tests and is suitable for rapid screening and evaluation of material properties; precise control of the aging box temperature and oxygen flow rate ensures the stability and consistency of the experimental conditions, reduces experimental errors, and improves the repeatability and reliability of the experimental results.

[0076] Through standardized sample preparation and experimental process, the consistency of samples and the reliability of experimental results are ensured. This method is suitable for rapid aging evaluation of various cable materials and has broad application prospects; using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), infrared spectroscopy (FTIR) and other advanced characterization techniques, the aged samples are comprehensively analyzed, which can accurately evaluate the thermal stability, chemical composition changes and mechanical properties of the materials; compared with the traditional long-term aging test method, this method can significantly save experimental time and cost, improve laboratory work efficiency and resource utilization; the aging characteristic data obtained by this method can provide an important basis for the selection, formulation optimization and quality control of cable materials, guide cable design and maintenance in practical applications, and improve the reliability and life of cable systems; this method is suitable for various types of cable materials, not only limited to cross-linked polyethylene (XLPE), but can also be extended to other polymer materials, such as polypropylene (PP), polyvinyl chloride (PVC), etc., and has broad application prospects.

[0077] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A power cable insulation material detection device, characterized in that: include, High temperature aging chamber, which is used to simulate the high temperature environment of the insulation material; Temperature control equipment, which is used to control the temperature in the high-temperature aging box; Oxygen supply equipment, which is used to supply oxygen to the high-temperature aging box; A fixture, which is used to clamp and fix the insulating material sample to be tested; The aging of insulating materials is simulated by the oxygen supply of the oxygen supply equipment and the high temperature environment provided by the high temperature aging box.

2. The power cable insulation material detection device according to claim 1, characterized in that: Also includes, The solenoid valve is arranged between the high temperature aging box and the oxygen supply equipment, and is used to control the flow of oxygen entering the high temperature aging box.

3. The power cable insulation material detection device according to claim 2, characterized in that: Also includes, The temperature sensor is arranged in the high temperature aging box and is used to detect the temperature in the high temperature aging box in real time.

4. The power cable insulation material detection device according to claim 3, characterized in that: Also includes, The oxygen concentration sensor is arranged in the high temperature aging box and is used for real-time detection of the oxygen concentration in the high temperature aging box.

5. The power cable insulation material detection device according to claim 4, characterized in that: Also includes, A hanging rope, which is provided on the clamp and is used to hang the clamp; The weighing sensor is arranged in the high-temperature aging box, the suspension rope is connected to the weighing sensor, and the weighing sensor is used to measure the weight of the insulating material sample being tested.

6. The power cable insulation material detection device according to claim 5, characterized in that: Also includes, The camera equipment is installed in the high-temperature aging box and is used to observe the state of the sample.

7. The power cable insulation material detection device according to claim 6, characterized in that: The clamp is made of high temperature resistant material.

8. A method for detecting thermal oxidation aging of power cable insulation materials, characterized in that: include, Cutting samples from cable material; A thermal oxygen aging test is carried out using the power cable insulation material detection device as described in any one of claims 1 to 7; Characterize and analyze samples; Conduct tensile test and impact test.

9. The thermal oxygen aging detection method for power cable insulation material according to claim 8, characterized in that: The thermal oxidation aging test includes: Place the sample in a high temperature aging box at 149-151°C, keep the oxygen concentration in the box greater than 21%, and conduct a 48-hour aging test; The physical properties of the sample are recorded at predetermined time intervals.

10. The thermal oxidation aging detection method for power cable insulation material according to claim 9, characterized in that: The aged samples were characterized and analyzed using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and infrared spectroscopy (FTIR).

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