Simulation device and simulation method for arc fault in transformer oil
By designing an arc fault simulation device in transformer oil, including an arc-induced device and a winding simulation mechanism, the problem of inability to effectively simulate arc faults in the prior art is solved, and accurate simulation of arc faults and pressure characteristics analysis are realized.
Patent Information
- Application Number
- CN202411967116.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-03-07
AI Technical Summary
In the prior art, the arc fault site structure in the transformer oil cannot effectively simulate the arc fault, which affects the accurate analysis of the arc fault pressure characteristics.
An arc fault simulation device in transformer oil is designed, including a transformer cavity for containing insulating oil. The arc-induced device and a winding simulation mechanism are penetrated through the cavity. The winding simulation mechanism is located on the side of the arc-induced device. By setting an insulating annular cylinder and an industrial frequency source, arc faults of different strengths are simulated.
The device can accurately reduce the structure around the winding when an arc fault occurs in the transformer oil, significantly improving the accuracy of arc fault simulation, and measuring and recording pressure data through pressure probes and oscilloscopes, providing a detailed data basis for arc fault research.
Smart Images
Figure CN119575106A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of power transmission and transformation of electric power systems, and in particular relates to a device for simulating arc faults in transformer oil, and also relates to a method for simulating arc faults in transformer oil. Background Art
[0002] Power transformers are vital to the safe and stable operation of power systems. When an arc discharge occurs inside an oil-immersed power transformer, the arc will vaporize and crack the transformer oil, generating bubbles that wrap around the arc. As the arc deposits energy on a millisecond scale, the bubbles expand rapidly. Due to the weak compressibility of the transformer oil, overpressure will occur inside the transformer. High-energy arc faults can even cause the box to rupture, and the high-temperature cracking gas and oil mist coming into contact with air may cause a secondary explosion, further exacerbating the hazards of arc faults.
[0003] The generation and evolution of arc-induced bubbles determine the pressure characteristics of arc faults in transformer oil. The evolution of arc-induced bubbles is not only affected by arc discharge, but also has a great relationship with the structure of the arc fault site.
[0004] When studying the pressure characteristics of arc faults in transformer oil, due to cost constraints, the transformer windings and other structures are generally removed, and only an arc-starting device is arranged inside the transformer cavity. The arc-starting device consists of two symmetrical rod electrodes and a copper wire in the middle. The device generates an arc by melting the copper wire during discharge, and arc faults generally occur near the windings. In practice, the structure of the arc fault site is completely different from the currently commonly used structure, which is bound to affect the accurate analysis of the pressure characteristics of the arc fault. Summary of the invention
[0005] The first purpose of the present invention is to provide a device for simulating arc faults in transformer oil, which solves the technical problem that the arc fault location structure commonly used in the prior art cannot effectively simulate arc faults.
[0006] A second object of the present invention is to provide a method for simulating arc faults in transformer oil.
[0007] The first technical solution adopted by the present invention is an arc fault simulation device in transformer oil, including a transformer cavity for containing insulating oil, an arc striking device is provided horizontally through the transformer cavity, a winding simulation mechanism is connected inside the transformer cavity, and the winding simulation mechanism is located on the side of the arc striking device.
[0008] The first technical solution of the present invention is also characterized in that: The arc striking device comprises a copper wire, and rod electrodes and electrode connecting rods are symmetrically connected at both ends of the copper wire in sequence, and the electrode connecting rod passes through the transformer cavity.
[0009] Through holes are opened on two corresponding side walls of the transformer cavity; insulating annular cylinders are sealed and connected in the two through holes, and the insulating annular cylinders are sleeved on the outer periphery of the electrode connecting rod.
[0010] The insulating annular cylinder is made of epoxy resin.
[0011] The winding simulation mechanism comprises a horizontally placed insulating plate, the insulating plate comprises a first insulating plate and a second insulating plate, the first insulating plate is located on the top of the copper wire, and the second insulating plate is located on the bottom of the copper wire; An insulating plate connecting rod is provided between the first insulating plate and the second insulating plate, and the insulating plate connecting rod includes an integrally formed connecting portion a and a supporting portion a, the outer diameter of the connecting portion a is smaller than the outer diameter of the supporting portion a, an outer circumference of the connecting portion a is provided with an external thread, the connecting portion a passes through the first insulating plate, and the connecting portion a and the first insulating plate are threadedly connected by a nut; an inner cavity at the bottom of the supporting portion a is provided with an internal thread; A support rod is provided at the bottom of the second insulating plate, and the support rod includes an integrally formed connecting part b and a supporting part b. The outer diameter of the connecting part b is smaller than the outer diameter of the supporting part b. An external thread is provided on the outer periphery of the connecting part b. The connecting part b passes through the second insulating plate and is connected with the internal thread of the supporting part a. The supporting part b is fixedly connected to the bottom wall of the transformer cavity.
[0012] The winding simulation mechanism includes a horizontally placed insulating plate, which is located at the bottom of the copper wire; A support rod is provided at the bottom of the insulating plate, and the support rod includes an integrally formed connecting portion c and a supporting portion c. The outer diameter of the connecting portion c is smaller than the outer diameter of the supporting portion c. An external thread is provided on the outer periphery of the connecting portion c. The connecting portion c passes through the insulating plate. The connecting portion c is threadedly connected to the insulating plate through a nut, and the supporting portion b is fixedly connected to the bottom wall of the transformer cavity.
[0013] The insulating plate comprises an arc-shaped portion bent toward the top of the transformer cavity, and horizontally arranged mounting portions are integrally formed on both sides of the arc-shaped portion; the mounting portions are used for fixing the insulating plate.
[0014] A pressure probe is provided through the transformer cavity, and the pressure probe signal is connected to an oscilloscope; the ends of the two electrode connecting rods extending out of the transformer cavity are connected in series with a power frequency source and a circuit breaker.
[0015] The second technical solution adopted by the present invention is a method for simulating an arc fault in transformer oil, which adopts the above-mentioned device for simulating an arc fault in transformer oil, and comprises the following steps: S1: Check the cleanliness of the transformer cavity and the connection of the copper wire. At the same time, check whether the part where the electrode connecting rod passes through the transformer cavity is well sealed to avoid leakage of insulating oil; S2: Select different insulating plates according to the simulation situation, install the insulating plates inside the transformer cavity, and make the insulating plates located on the side of the copper wire; S3: slowly inject insulating oil into the transformer cavity; S4: Close the circuit breaker in the external circuit, and the power frequency source connected to the electrode connecting rod generates current to flow through the copper wire in the arc striking device, generating an arc between the rod electrodes. By adjusting the power frequency source parameters, arc faults of different intensities can be simulated. The pressure is measured by the pressure probe on the cavity wall, and the data is recorded by the oscilloscope; S5: After the arc discharge ends, the insulating oil in the transformer cavity is discharged to complete the simulation of the arc fault in the transformer oil.
[0016] The second technical solution of the present invention is also characterized in that: Compared with the prior art, the present invention has the following beneficial effects: The present invention sets up a winding simulation mechanism, and according to the different composition forms and specific connection methods of the insulating plates in the winding simulation mechanism, has an arc portion and a mounting portion that can better fit the actual winding shape, so as to accurately restore the structure of the parts around the winding when an arc fault occurs in the transformer oil, thereby effectively improving the accuracy of the arc fault simulation.
[0017] The present invention seals and connects an insulating annular cylinder made of epoxy resin in a through hole opened on the side wall of the transformer cavity. The epoxy resin material itself has excellent insulation performance and chemical stability. On the one hand, it can prevent current leakage and ensure the electrical safety of the device during operation; on the other hand, it can ensure good sealing inside the transformer cavity, avoid leakage of insulating oil, and maintain a stable internal insulating oil environment, which is very important for continuously and stably carrying out arc fault simulation experiments.
[0018] The connection structure of the copper wire, the rod electrode and the electrode connecting rod in the arc striking device of the present invention is convenient for use with external power frequency source equipment. By changing the relevant parameters of the external power frequency source, arcs of different strengths can be generated between the rod electrodes. Combined with the winding simulation mechanism, arc fault scenarios in transformer oil under various degrees and conditions can be simulated to meet diverse research and testing needs. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 1 is a schematic structural diagram of Embodiment 4 of the arc fault simulation device in transformer oil of the present invention; Figure 2 1 is a schematic diagram of the structure of Embodiment 5 of the arc fault simulation device in transformer oil of the present invention; Figure 3 It is a structural schematic diagram of an insulating plate in a transformer oil arc fault simulation device of the present invention; Figure 4 It is a structural schematic diagram of Example 6 of the arc fault simulation device in transformer oil of the present invention.
[0020] In the figure, 1. transformer cavity, 2. insulating oil, 3. rod electrode, 4. copper wire, 5. electrode connecting rod, 6. insulating annular cylinder, 7. insulating plate, 8. support rod, 9. screw, 10. insulating plate connecting rod, 11. power frequency source, 12. circuit breaker, 13. oscilloscope, 14. pressure probe. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0022] Example 1 like Figure 1-4 As shown, the transformer oil arc fault simulation device disclosed in this embodiment includes a transformer cavity 1 for containing insulating oil 2, an arc-starting device is provided through the transformer cavity 1 in the horizontal direction, a winding simulation mechanism is connected inside the transformer cavity 1, and the winding simulation mechanism is located on the side of the arc-starting device, a pressure probe 14 is provided through the transformer cavity 1, and the pressure probe 14 signal is connected to an oscilloscope 13; the ends of the two electrode connecting rods 5 extending out of the transformer cavity 1 are connected in series with an industrial frequency source 11 and a circuit breaker 12.
[0023] The transformer oil arc fault simulation device disclosed in this embodiment has a transformer cavity 1 specifically used for containing insulating oil 2, which provides a basic closed space for the entire simulation environment, ensures that the insulating oil can work in a stable environment, and provides necessary conditions for subsequent arc generation and fault simulation. The transformer cavity 1 is cleverly provided with an arc-starting device in the horizontal direction. The arc-starting device is a key part of the entire simulation device, which can accurately trigger an arc in the transformer oil environment, thereby simulating the arc fault situation that may occur inside the transformer. Inside the transformer cavity 1, a winding simulation mechanism is also connected, and the winding simulation mechanism is located at the lateral position of the arc-starting device. The design of the winding simulation mechanism is extremely important for simulating the actual arc fault working conditions of the transformer. It can simulate the interaction between the transformer winding and the arc during the arc formation and evolution process, such as affecting the arc motion and discharge parameters by affecting the pressure distribution around the arc. The change of the arc state in turn affects the pressure distribution. The pressure probe 14 and the oscilloscope 13 are used to measure the oil pressure at different positions, providing a detailed data basis for arc fault pressure analysis.
[0024] This complete set of equipment provides an extremely effective simulation platform for in-depth research on arc faults in transformer oil, helping researchers and engineers to better understand the occurrence mechanism and development process of arc faults in transformer oil and the internal overpressure of the transformer, thereby laying a solid foundation for the development of more reliable and efficient transformer protection measures and fault diagnosis technologies.
[0025] Example 2 The transformer oil arc fault simulation device disclosed in this embodiment includes a transformer cavity 1 for containing insulating oil 2, an arc striking device is provided through the transformer cavity 1 in the horizontal direction, a winding simulation mechanism is connected inside the transformer cavity 1, and the winding simulation mechanism is located laterally to the arc striking device. The arc striking device includes a copper wire 4, and rod electrodes 3 and electrode connecting rods 5 are symmetrically connected at both ends of the copper wire 4 in sequence, and the electrode connecting rods 5 pass through the transformer cavity 1.
[0026] In this embodiment, the arc striking device includes a copper wire 4, and the two ends of the copper wire 4 are symmetrically connected to the rod electrode 3 and the electrode connecting rod 5 in sequence. During the arc striking process, the rod electrode 3 can effectively guide the current and generate an arc by melting the copper wire, while the electrode connecting rod 5 has the important mission of connecting the entire arc striking device with the external circuit, and it can pass through the transformer cavity 1, ensuring a stable connection with external power frequency source and other equipment, thereby ensuring reliable arc striking.
[0027] Example 3 The arc fault simulation device in transformer oil disclosed in this embodiment includes a transformer cavity 1 for containing insulating oil 2, an arc-starting device is provided through the transformer cavity 1 in the horizontal direction, a winding simulation mechanism is connected inside the transformer cavity 1, and the winding simulation mechanism is located laterally to the arc-starting device. The arc-starting device includes a copper wire 4, and rod electrodes 3 and electrode connecting rods 5 are symmetrically connected at both ends of the copper wire 4 in sequence, and the electrode connecting rods 5 pass through the transformer cavity 1. Through holes are provided on the two corresponding side walls of the transformer cavity 1; insulating annular cylinders 6 are sealed and connected in the two through holes, and the insulating annular cylinders 6 are sleeved on the outer periphery of the electrode connecting rods 5. The insulating annular cylinder 6 is made of epoxy resin.
[0028] In this embodiment, through holes are opened on the two corresponding side walls of the transformer cavity 1, and the two through holes are sealed with insulating annular tubes 6, and the insulating annular tubes 6 are tightly sleeved on the outer periphery of the electrode connecting rod 5. This design ensures that the electrode connecting rod 5 can smoothly pass through the side wall of the transformer cavity 1 to achieve connection with the outside, and on the other hand, it ensures the sealing inside the transformer cavity 1, prevents leakage of insulating oil, and maintains a stable internal insulation environment. In addition, the insulating annular tube 6 is made of epoxy resin, which has excellent insulation performance and chemical stability, can effectively prevent current leakage during long-term use, and ensure the safety and reliability of the entire simulation device. Even in a high voltage environment, it can stably play its insulating role, providing a solid guarantee for the normal operation of the arc-starting device, so that the entire transformer oil arc fault simulation device can simulate arc faults more stably, and provide strong support for fault research and protection measures for the power system.
[0029] Example 4 The arc fault simulation device in transformer oil disclosed in this embodiment includes a transformer cavity 1 for containing insulating oil 2, an arc-starting device is provided through the transformer cavity 1 in the horizontal direction, a winding simulation mechanism is connected inside the transformer cavity 1, and the winding simulation mechanism is located laterally to the arc-starting device. The arc-starting device includes a copper wire 4, and rod electrodes 3 and electrode connecting rods 5 are symmetrically connected at both ends of the copper wire 4 in sequence, and the electrode connecting rods 5 pass through the transformer cavity 1. The winding simulation mechanism includes a horizontally placed insulating plate 7, and the insulating plate 7 includes a first insulating plate and a second insulating plate, the first insulating plate is located at the top of the copper wire 4, and the second insulating plate is located at the bottom of the copper wire 4; An insulating plate connecting rod 10 is provided between the first insulating plate and the second insulating plate. The insulating plate connecting rod 10 includes an integrally formed connecting portion a and a supporting portion a. The outer diameter of the connecting portion a is smaller than the outer diameter of the supporting portion a. The outer periphery of the connecting portion a is provided with an external thread. The connecting portion a passes through the first insulating plate. The connecting portion a and the first insulating plate are threadedly connected by a nut 9. The inner cavity at the bottom of the supporting portion a is provided with an internal thread. A support rod 8 is provided at the bottom of the second insulating plate, and the support rod 8 includes an integrally formed connecting portion b and a supporting portion b. The outer diameter of the connecting portion b is smaller than the outer diameter of the supporting portion b. An external thread is provided on the outer periphery of the connecting portion b. The connecting portion b passes through the second insulating plate and is connected to the internal thread of the supporting portion a. The supporting portion b is fixedly connected to the bottom wall of the transformer cavity 1.
[0030] This embodiment is a simulation structure of the inter-turn arc fault position of the middle layer of the winding. The winding simulation mechanism includes a horizontally placed insulating plate 7, which is composed of a first insulating plate and a second insulating plate, which are respectively located at the top and bottom of the copper wire 4. This layered arrangement can more accurately simulate the distribution of the windings in the actual transformer, making the simulation results more meaningful for reference. The first insulating plate and the second insulating plate are connected by an insulating plate connecting rod 10, which includes an integrally formed connecting portion a and a supporting portion a. The outer diameter of the connecting portion a is smaller than the outer diameter of the supporting portion a. The outer periphery of the connecting portion a is provided with an external thread. The connecting portion a passes through the first insulating plate and is threadedly connected to the nut 9. This connection method is not only convenient for installation and disassembly, but also ensures the stability and reliability of the connection. At the same time, the inner cavity at the bottom of the support part a is provided with an internal thread, which matches the support rod 8 at the bottom of the second insulating plate. The support rod 8 also includes an integrally formed connecting part b and a supporting part b. The outer diameter of the connecting part b is smaller than the outer diameter of the supporting part b. The outer periphery of the connecting part b is provided with an external thread. After the connecting part b passes through the second insulating plate, it is connected with the internal thread of the supporting part a. The supporting part b is fixedly connected to the bottom wall of the transformer cavity 1. Such a structural design ensures that the winding simulation mechanism can ensure the integrity of the structure and the stability of the position even if it is subjected to strong pressure shock and insulating oil oscillation during the experiment, which provides a strong guarantee for the accurate simulation of arc faults.
[0031] Example 5 The arc fault simulation device in transformer oil disclosed in this embodiment includes a transformer cavity 1 for containing insulating oil 2, an arc-starting device is provided through the transformer cavity 1 in the horizontal direction, a winding simulation mechanism is connected inside the transformer cavity 1, and the winding simulation mechanism is located laterally to the arc-starting device. The arc-starting device includes a copper wire 4, and rod electrodes 3 and electrode connecting rods 5 are symmetrically connected at both ends of the copper wire 4 in sequence, and the electrode connecting rods 5 pass through the transformer cavity 1. The winding simulation mechanism includes a horizontally placed insulating plate 7, and the insulating plate 7 is located at the bottom of the copper wire 4; A support rod 8 is provided at the bottom of the insulating plate 7, and the support rod 8 includes an integrally formed connecting portion c and a supporting portion c. The outer diameter of the connecting portion c is smaller than the outer diameter of the supporting portion c. An external thread is provided on the outer periphery of the connecting portion c. The connecting portion c passes through the insulating plate 7. The connecting portion c and the insulating plate 7 are threadedly connected by a nut 9, and the supporting portion b is fixedly connected to the bottom wall of the transformer cavity 1.
[0032] This embodiment is a structure for simulating arc faults between turns in the outermost or innermost layer of the winding. The winding simulation mechanism connected inside the transformer cavity 1 is located on the side of the arc-starting device. The winding simulation mechanism of this embodiment is specially designed for simulating arc faults between turns in the outermost or innermost layer of the winding. It includes an insulating plate 7 placed horizontally and located at the bottom of the copper wire 4. The support rod 8 arranged at the bottom of the insulating plate 7 plays a key supporting role. The support rod 8 is composed of an integrally formed connecting portion c and a supporting portion c. The outer diameter of the connecting portion c is smaller than the outer diameter of the supporting portion c. The outer periphery of the connecting portion c is provided with an external thread. The connecting portion c passes through the insulating plate 7 and is threadedly connected to the nut 9. This connection method not only ensures the stability of the connection between the insulating plate 7 and the support rod 8, but also facilitates installation and disassembly, and is convenient for adjusting and maintaining the winding simulation mechanism during the experiment. The support portion c is fixedly connected to the bottom wall of the transformer cavity 1, so that the entire winding simulation mechanism can be fixed at a predetermined position in the transformer cavity 1. Even if it is subjected to strong pressure shock and insulating oil vibration during the experiment, the integrity of the structure and the stability of the position can be guaranteed, thereby providing a solid guarantee for simulating arc faults between the outermost or innermost turns of the winding.
[0033] In combination with Examples 4-5, the entire transformer oil arc fault simulation device can highly restore the transformer oil arc fault situation under actual working conditions through the fine design and reasonable layout of each component, providing indispensable experimental data and technical support for transformer arc fault research, cavity explosion-proof design, etc., which is helpful to promote the technological development of the power industry and ensure the stable operation of the power system.
[0034] Example 6 On the basis of Embodiment 4 or 5, the insulating plate 7 in this embodiment includes an arc-shaped portion bent toward the top of the transformer cavity 1, and horizontally arranged mounting portions are integrally formed on both sides of the arc-shaped portion; the mounting portions are used to fix the insulating plate 7.
[0035] In this embodiment, the cross section of the insulating plate 7 is similar to the cross section of the winding, and the equivalence of the winding structure can be achieved. In this embodiment, the arc fault simulation device in transformer oil is further optimized and improved to make its simulation effect more accurate and close to the actual situation. The insulating plate 7 includes an arc-shaped portion bent toward the top of the transformer cavity 1. This unique arc design makes the insulating plate 7 more structurally consistent with the actual shape of the winding, and can better simulate the bending shape of the winding inside the transformer. The arc-shaped portion is integrally formed with a horizontally arranged mounting portion on both sides. The presence of the mounting portion provides a convenient and stable way for the fixing of the insulating plate 7, ensuring that the insulating plate 7 can be accurately maintained in a predetermined position in the transformer cavity 1, and will not be displaced due to various vibrations and impacts during the simulation process, thereby ensuring the accuracy and stability of the simulation. In this embodiment, the cross section of the insulating plate 7 is similar to the cross section of the winding. This design feature enables the insulating plate 7 to achieve the equivalence of the winding structure to a large extent. Through this equivalent design, when an arc fault occurs between the outermost or innermost turns of the simulated winding, it can more realistically reflect the interaction between the winding and the arc and arc-induced bubbles during the actual arc fault process. This not only helps to deeply study the pressure characteristics of transformer arc, but also provides more reliable experimental data for the explosion-proof design of transformer cavity.
[0036] The present invention also discloses a method for simulating an arc fault in transformer oil, which uses the above-mentioned device for simulating an arc fault in transformer oil and comprises the following steps: S1: Check the cleanliness of the transformer cavity 1 and the connection of the copper wire 4. At the same time, check whether the part where the electrode connecting rod 5 passes through the transformer cavity 1 is well sealed to avoid leakage of the insulating oil 2; First, check whether the transformer cavity 1 is intact and ensure that its interior is clean and free of impurities, especially to ensure that there is no residual foreign matter in the cavity part containing the insulating oil 2, so as not to affect the subsequent simulation experiment results; for the arc-starting device, carefully check the connection of the copper wire 4 to ensure that its two ends are firmly connected to the rod electrode 3 and the electrode connecting rod 5 without looseness or virtual connection. At the same time, check whether the part where the electrode connecting rod 5 passes through the transformer cavity 1 is well sealed to avoid leakage of insulating oil; for the through holes on the side wall of the transformer cavity 1 and the sealed insulating annular tube 6, check their sealing to ensure that the insulating annular tube 6 is tightly fitted on the outer periphery of the electrode connecting rod 5 and has no damage or cracks, especially when the insulating annular tube 6 is made of epoxy resin, pay attention to whether the material shows signs of aging or damage to ensure its good insulation performance; S2: Select different insulating plates 7 according to the simulation situation, install the insulating plates 7 inside the transformer cavity 1, and make the insulating plates 7 lateral to the copper wire 4; In terms of the winding simulation mechanism, if a structure including a first insulating plate and a second insulating plate is used, it is necessary to confirm that the connection part a of the insulating plate connecting rod 10 is tightly threadedly connected to the first insulating plate through a nut 9, the internal thread of the inner cavity at the bottom of the support part a is firmly threadedly connected to the connection part b of the support rod 8 at the bottom of the second insulating plate, and the support part b is firmly fixed to the bottom wall of the transformer cavity 1. If it is a structure that only contains an insulating plate 7 placed horizontally at the bottom of the copper wire 4, it is necessary to check whether the connection part c of the insulating plate 7 and the support rod 8 is reliably connected through the nut 9, and the fixation of the support part c to the bottom wall of the transformer cavity 1. In addition, for the arc-shaped portion and the mounting portion on the insulating plate 7, it is necessary to ensure that their shapes are complete and the mounting portion can be used normally to fix the insulating plate 7; S3: slowly inject insulating oil 2 into the transformer cavity 1; Through a special oil filling port, slowly inject insulating oil 2 that meets the experimental requirements into the transformer cavity 1 to ensure that the predetermined oil level is reached; S4: Close the circuit breaker 12 in the external circuit, and the power frequency source 11 connected to the electrode connecting rod 5 generates a current to flow through the copper wire 4 in the arc striking device, and an arc is generated between the rod electrodes 3. By adjusting the parameters of the power frequency source 11, arc faults of different intensities are simulated, and the pressure is measured by the pressure probe 14 on the cavity wall, and the data is recorded by the oscilloscope 13; Connect the electrode connecting rod 5 to the external power frequency source 11. Ensure that the connection line has good contact and set the charging voltage according to the experiment to ensure the required arc energy and thus achieve the expected arc fault. At the same time, pay attention to the insulation protection measures of the line to prevent safety accidents such as leakage. The circuit breaker is closed, and the current passes through the copper wire 4 in the arc striking device to generate an arc between the rod electrodes 3. The pressure in the oil at different positions is measured by the pressure probe 14 installed on the transformer cavity 1, providing a detailed data basis for the arc fault pressure analysis; S5: After the arc discharge ends, the insulating oil 2 in the transformer cavity 1 is discharged to complete the simulation of the arc fault in the transformer oil.
[0037] After the arc fault experiment is completed, the insulating oil 2 in the transformer cavity 1 is discharged, and the device is comprehensively inspected and cleaned to check the wear and tear of each component, especially the rod electrode 3, copper wire 4 in the arc striking device and the insulating plate 7, support rod 8 and other components in the winding simulation mechanism. If there are damaged or severely worn parts, they should be replaced or repaired in time so that the device can carry out the next simulation experiment to ensure the accuracy and reliability of the experimental results.
[0038] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.
[0039] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0040] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those 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 application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A device for simulating arc faults in transformer oil, characterized in that: It comprises a transformer cavity (1) for containing insulating oil (2), wherein an arc striking device is provided through the transformer cavity (1) in the horizontal direction, and a winding simulation mechanism is connected inside the transformer cavity (1), wherein the winding simulation mechanism is located to the side of the arc striking device.
2. The transformer oil arc fault simulation device according to claim 1, characterized in that: The arc striking device comprises a copper wire (4), with rod electrodes (3) and electrode connecting rods (5) symmetrically connected to both ends of the copper wire (4) in sequence, and the electrode connecting rods (5) passing through the transformer cavity (1).
3. The transformer oil arc fault simulation device according to claim 2, characterized in that: Through holes are formed on two corresponding side walls of the transformer cavity (1); insulating annular cylinders (6) are sealed and connected in the two through holes, and the insulating annular cylinders (6) are sleeved on the outer circumference of the electrode connecting rod (5).
4. The transformer oil arc fault simulation device according to claim 3, characterized in that: The insulating annular cylinder (6) is made of epoxy resin.
5. The transformer oil arc fault simulation device according to claim 2, characterized in that: The winding simulation mechanism comprises a horizontally placed insulating plate (7), the insulating plate (7) comprising a first insulating plate and a second insulating plate, the first insulating plate being located on the top of the copper wire (4) and the second insulating plate being located on the bottom of the copper wire (4); An insulating plate connecting rod (10) is provided between the first insulating plate and the second insulating plate, the insulating plate connecting rod (10) comprising an integrally formed connecting portion a and a supporting portion a, the outer diameter of the connecting portion a being smaller than the outer diameter of the supporting portion a, the outer circumference of the connecting portion a being provided with an external thread, the connecting portion a passing through the first insulating plate, the connecting portion a and the first insulating plate being threadedly connected via a nut (9); the inner cavity at the bottom of the supporting portion a being provided with an internal thread; A support rod (8) is provided at the bottom of the second insulating plate, the support rod (8) comprising an integrally formed connecting portion b and a supporting portion b, the outer diameter of the connecting portion b being smaller than the outer diameter of the supporting portion b, an outer circumference of the connecting portion b being provided with an external thread, the connecting portion b passing through the second insulating plate and being connected to the internal thread of the supporting portion a, the supporting portion b being fixedly connected to the bottom wall of the transformer cavity (1).
6. The transformer oil arc fault simulation device according to claim 2, characterized in that: The winding simulation mechanism comprises a horizontally placed insulating plate (7), wherein the insulating plate (7) is located at the bottom of the copper wire (4); A support rod (8) is provided at the bottom of the insulating plate (7), the support rod (8) comprising an integrally formed connection portion c and a support portion c, the outer diameter of the connection portion c being smaller than the outer diameter of the support portion c, an outer circumference of the connection portion c being provided with an external thread, the connection portion c passing through the insulating plate (7), the connection portion c being threadedly connected to the insulating plate (7) via a nut (9), and the support portion b being fixedly connected to the bottom wall of the transformer cavity (1).
7. The transformer oil arc fault simulation device according to claim 5 or 6, characterized in that: The insulating plate (7) comprises an arc-shaped portion bent towards the top of the transformer cavity (1), and horizontally arranged mounting portions are integrally formed on both sides of the arc-shaped portion; the mounting portions are used to fix the insulating plate (7).
8. The transformer oil arc fault simulation device according to claim 1, characterized in that: A pressure probe (14) is provided through the transformer cavity (1), and the pressure probe (14) signal is connected to an oscilloscope (13); the ends of the two electrode connecting rods (5) extending out of the transformer cavity (1) are connected in series with a power frequency source (11) and a circuit breaker (12).
9. A method for simulating an arc fault in transformer oil, using the device for simulating an arc fault in transformer oil as claimed in claim 5 or 6, characterized in that: The following steps are involved: S1: Check the cleanliness of the transformer cavity (1) and the connection of the copper wire (4). At the same time, check whether the part where the electrode connecting rod (5) passes through the transformer cavity (1) is well sealed to avoid leakage of the insulating oil (2); S2: selecting different insulating plates (7) according to the simulation situation, installing the insulating plates (7) inside the transformer cavity (1), and positioning the insulating plates (7) on the side of the copper wire (4); S3: slowly injecting insulating oil (2) into the transformer cavity (1); S4: closing the circuit breaker (12) in the external circuit, and the power frequency source (11) connected to the electrode connecting rod (5) generates a current to flow through the copper wire (4) in the arc striking device, thereby generating an arc between the rod electrodes (3). By adjusting the parameters of the power frequency source (11), arc faults of different intensities are simulated, and the pressure is measured by a pressure probe (14) on the wall of the cavity, and the data is recorded by an oscilloscope (13); S5: After the arc discharge ends, the insulating oil (2) in the transformer cavity (1) is discharged to complete the simulation of the arc fault in the transformer oil.