Transformer state measurement method based on built-in optical fiber

Abstract

The invention relates to a transformer state measurement method based on built-in optical fibers, and belongs to the technical field of transformer coil monitoring. The transformer state measurement method based on the built-in optical fiber comprises the following steps: manufacturing a copper bar embedded with the optical fiber, taking the copper bar embedded with the optical fiber as a part of a transformer coil, and fixing one end of the copper bar with a copper bar in a transformer winding coil, the other end of the optical fiber connector assembly is fixed with a transformer bushing joint or a transformer on-load tap-changer joint; an optical fiber connector assembly is arranged on the transformer casing; one end of the optical fiber in the copper bar embedded with the optical fiber is pulled to the outside of the copper bar and is connected with the optical fiber connector assembly, the optical fiber connector assembly is connected with information parameter detection equipment outside the transformer, and the information parameter detection equipment processes signals transmitted back by the optical fiber in real time. Feature information reflecting the state of the transformer coil is extracted, the feature information of the state of the transformer coil comprises temperature information and vibration information of the transformer coil, and measurement of the state of the transformer coil is completed.

Description

Technical Field

[0001] The present invention belongs to the technical field of transformer coil monitoring, and in particular relates to a transformer state measurement method based on built-in optical fiber. Background Art

[0002] As a critical component of power systems, the operating status of transformers is directly related to their safety and stability. Transformer coils, as core components, are affected by a variety of factors during operation, such as current, voltage, and ambient temperature. These factors can easily lead to abnormal temperature rise and vibration. Excessive temperatures can accelerate the aging of the coil insulation, degrading insulation performance and even causing insulation breakdown. Therefore, real-time and accurate monitoring of the transformer coil status is crucial.

[0003] At present, the commonly used transformer coil condition monitoring methods mainly include the following: 1. Thermocouple temperature measurement method: Thermocouple is a temperature sensor based on the thermoelectric effect. It determines the temperature by measuring the thermoelectric potential at both ends of the thermocouple. Although this method has advantages such as high measurement accuracy and fast response speed, it has the following disadvantages: Complex installation: Multiple thermocouples need to be installed on the transformer coil. The installation process is cumbersome and can easily affect the insulation performance of the coil.

[0004] Low spatial resolution: Due to the limited number of thermocouples, it is difficult to achieve distributed measurement of transformer coil temperature, and it is impossible to accurately obtain the temperature distribution of various parts of the coil.

[0005] Susceptible to electromagnetic interference: In the strong electromagnetic environment of the transformer, the measurement signal of the thermocouple is easily interfered with, resulting in inaccurate measurement results.

[0006] 2. Infrared thermal imaging method: An infrared thermal imager is used to receive infrared energy radiated from the transformer coil surface and convert it into a temperature image, thereby monitoring the coil temperature. This method has the advantages of non-contact measurement and intuitive display of temperature distribution, but it also has some limitations: Limited measurement depth: Only the temperature of the coil surface can be measured, and the temperature inside the coil cannot be accurately obtained. The temperature changes inside the coil can often better reflect its actual operating status.

[0007] Affected by environmental factors: Ambient temperature, humidity, dust and other factors will have a great impact on the measurement results of infrared thermal imaging, resulting in large measurement errors.

[0008] In summary, the existing transformer coil status monitoring methods have problems such as complex installation, low spatial resolution, susceptibility to interference, and inability to comprehensive monitoring, which makes it difficult to meet the needs of real-time and accurate monitoring of transformer coil status. Summary of the Invention

[0009] Based on the problems existing in the above background technology, the present invention proposes a transformer state measurement method based on built-in optical fiber, which solves the problem that the existing transformer coil state monitoring method is difficult to achieve distributed measurement of transformer coil temperature and cannot accurately obtain the vibration information and temperature information of various parts of the coil.

[0010] The embodiment of the present invention is achieved as follows: An embodiment of the present invention provides a transformer state measurement method based on a built-in optical fiber, comprising the following steps: Step 1: manufacturing a copper bar embedded with an optical fiber; Step 2: The copper bar embedded with the optical fiber is used as part of the transformer coil, with one end of the copper bar fixed to the copper bar in the transformer winding coil and the other end fixed to the connection of the transformer bushing or the connection of the transformer on-load tap changer; Step 3: Install an optical fiber connector assembly on the transformer housing, pull one end of the optical fiber embedded in the copper bar to the outside of the copper bar and connect it to the optical fiber connector assembly; Step 4: Connect the optical fiber connector assembly to the information parameter detection equipment outside the transformer; Step 5: The information parameter detection device processes the signal transmitted back by the optical fiber in real time, extracts characteristic information reflecting the state of the transformer coil, which includes the temperature information and vibration information of the transformer coil, and completes the measurement of the transformer coil state.

[0011] Furthermore, in step 1, the copper bar embedded with the optical fiber includes an outer copper bar, an optical fiber and an inner copper bar, a mounting groove is provided at a middle position along the length direction of one end face of the outer copper bar, an optical fiber is glued into the mounting groove, the optical fiber is completely located inside the mounting groove, and one end face of the inner copper bar is pressed onto the end face of the outer copper bar with the mounting groove; one end of the optical fiber is located at one end of the outer copper bar and the inner copper bar, and the other end is located at the other end of the outer copper bar and the inner copper bar.

[0012] Furthermore, in step 1, a copper bar embedded with an optical fiber is manufactured using an embedding manufacturing device; the embedding manufacturing device includes a top cover and a bottom plate vertically spaced apart, wherein a hydraulic outer layer body, a hydraulic inner layer body, and a heating layer body having a cylindrical hollow structure with openings at both ends are sealed and detachably disposed between the top cover and the bottom plate; the hydraulic outer layer body, the hydraulic inner layer body, and the heating layer body are coaxially arranged; The hydraulic inner layer body is disposed within the hydraulic outer layer body, and the heating layer body is disposed within the hydraulic inner layer body; a hydraulic cavity is disposed between the hydraulic outer layer body and the hydraulic inner layer body, and the hydraulic cavity is connected to a hydraulic power source located outside the chassis; a molybdenum ribbon resistor is spirally wound around the inner circumferential surface of the heating layer body, and the molybdenum ribbon resistor is electrically connected to the heating power source outside the chassis; a first spiral groove is disposed on the outer circumferential surface of the heating layer body along its height direction; Four hydraulic annular surfaces are provided between the hydraulic inner layer body and the heating layer body, and the four hydraulic annular surfaces enclose a hydraulic tubular body. A second spiral groove is provided on the circumferential outer wall of the hydraulic tubular body, and the positions of the first spiral groove and the second spiral groove correspond to each other. A hydraulic driving member for pushing the four hydraulic annular surfaces toward the heating layer body and communicating with the hydraulic cavity is provided on the circumferential outer wall of the hydraulic inner layer body; The top cover is provided with a vacuum system, which is connected to the internal space of the heating layer body through two vacuum connecting holes on the top cover, and a vent hole is provided through the heating layer body; The hydraulic drive component includes 8 hydraulic cylinders connected to the hydraulic chamber, each hydraulic ring surface matches two hydraulic cylinders arranged vertically at intervals, the tail end of each hydraulic cylinder is fixedly connected to the circumferential outer wall of the hydraulic inner layer body, and the piston rod of each hydraulic cylinder is fixedly connected to the inner wall of the hydraulic ring surface; the hydraulic power source is arranged on the outside of the chassis and provides hydraulic power for the 8 hydraulic cylinders; the hydraulic power source includes an oil storage tank, an oil filling motor, an oil filling valve, an oil drain motor, an oil drain valve, an oil filling pipe and an oil drain pipe arranged on the outside of the chassis; a hydraulic oil inlet hole and a hydraulic oil outlet hole connected to the hydraulic chamber are opened on the chassis; one end of the oil filling pipe and the oil drain pipe are connected to the hydraulic oil inlet hole and the hydraulic oil outlet hole respectively, and the other end of the oil filling pipe and the oil drain pipe are both connected to the oil storage tank; the oil filling valve is provided on the oil filling pipe, and the oil filling valve is connected to the oil filling motor; the oil drain pipe is provided with the oil drain valve, and the oil drain valve is connected to the oil drain pipe; The method of manufacturing a copper bar embedded with optical fibers comprises the following steps: Step 1.1: Make two outer and inner copper bars of equal length; Step 1.2: Prepare an optical fiber whose length is greater than the length of the outer copper bar and the inner copper bar; Step 1.3: Create a mounting groove along the length of the outer copper strip in the middle of one end. Attach the optical fiber into the groove, with one end inside the outer copper strip and the other end outside. Step 1.4: Install the outer copper bar in a spiral shape in the first spiral groove, and install the inner copper bar in a spiral shape in the second spiral groove; Step 1.5: Start the vacuum system and the molybdenum ribbon resistor. When the temperature of the main heating layer is between 550°C and 600°C, start the hydraulic drive. The piston rods of the multiple hydraulic cylinders push the four hydraulic rings toward the main heating layer until the inner copper bar is pressed against the outer copper bar. After the piston rods of the hydraulic cylinders push the hydraulic rings to a pressure of 15 MPa and maintain it for 3 hours, the outer copper bar and the inner copper bar are tightly connected, forming a copper bar embedded with an optical fiber. Step 1.6: Stop pressurizing and heating, inject air, open the top cover, and remove the copper bar embedded with the optical fiber.

[0013] Furthermore, in step 3 and step 4, the optical fiber connector assembly includes a housing optical fiber connector, a housing sealing rubber ring, a housing mounting screw, an inner housing optical fiber connector, and an outer housing optical fiber connector; The housing optical fiber connector is a hollow cylindrical structure, and the housing optical fiber connector is transversely arranged on the transformer housing, and a housing sealing rubber ring and a housing mounting screw are respectively provided at both ends of the housing optical fiber connector; An inner fiber optic connector and an outer fiber optic connector are fixed at both ends of the casing respectively; the optical fiber outside the copper bar is connected to the inner fiber optic connector, and the information parameter detection equipment outside the transformer is connected to the outer fiber optic connector.

[0014] Furthermore, in step 4, the information parameter detection device includes a one-to-two coupler, a distributed optical fiber temperature sensing system, a distributed optical fiber vibration sensing system, and a microprocessor; The inlet end of the one-to-two coupler is connected to the optical fiber connector outside the casing, and the two outlet ends of the one-to-two coupler are respectively connected in parallel with the distributed optical fiber temperature sensing system and the distributed optical fiber vibration sensing system, and the microprocessor is electrically connected to the distributed optical fiber temperature sensing system and the distributed optical fiber vibration sensing system.

[0015] Furthermore, in step 5, the method for measuring the transformer coil state by the information parameter detection device includes the following steps: The method for measuring the transformer coil state by the information parameter detection device comprises the following steps: Step 5.1: The distributed optical fiber temperature sensing system measures the temperature data at different optical fiber locations and transmits the temperature data to the microprocessor, which records the temperature data as T k , where k=1, 2, 3, 4, 5..., n ,express n The temperature of each measuring point; T k The value indicates the measured temperature. Step 5.2: The distributed optical fiber vibration sensing system detects vibration data at different optical fiber positions and transmits the vibration data to the microprocessor, which records the vibration data as V ij ; i =1, 2, 3, 4, 5..., m ,express m Vibration of each measuring point; j =1, 2, 3, 4, 5, ..., g , which means g points are sampled each time. Step 5.3, respectively for i =1, 2, 3, 4, 5..., m , for vibration data V ij Perform Fourier transform to get V Fi ; Step 5.4, respectively for i =1, 2, 3, 4, 5..., m ,calculate T k Whether it exceeds the warning threshold T max If more than T max , then the warning, the warning position is i The position corresponding to the value; Step 5.5: i =1, 2, 3, 4, 5..., m , calculate V Fi Whether the amplitude of a certain frequency in exceeds the warning threshold V Fmax-a , a =1, 2, 3, 4, 5..., h , represents the discrete frequency calculated by Fourier transform; if V Fi The amplitude of a certain frequency exceeds the warning threshold V Fmax-a , then the warning, the warning position is i The corresponding position, the warning frequency is a The corresponding frequency.

[0016] The beneficial effects of the present invention are: 1. The transformer state measurement method based on built-in optical fiber provided by the present invention has an optical fiber directly embedded in a copper bar and fixed on the copper wire of the winding, forming an integral whole with the coil. This method can sense the state changes of the coil more directly and quickly, reducing the loss and interference in the signal transmission process and improving the monitoring sensitivity.

[0017] 2. The transformer status measurement method based on built-in optical fibers provided by this invention can simultaneously monitor the temperature and vibration of the transformer coil, providing more comprehensive information for transformer status assessment. Through comprehensive analysis of temperature and vibration, the operating status of the transformer can be more accurately determined, and potential safety hazards can be promptly identified.

[0018] 3. The transformer status measurement method based on built-in optical fiber provided by this invention has excellent resistance to electromagnetic interference and is unaffected by the strong electromagnetic environment inside the transformer, ensuring the accuracy and stability of the measurement signal. Furthermore, the optical fiber's long life and corrosion resistance enable long-term stable operation in harsh environments, improving the reliability of the entire monitoring system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without inventive work. The above and other objects, features and advantages of the present invention will become more apparent through the accompanying drawings. The same reference numerals indicate the same parts throughout the drawings. The drawings are not intentionally scaled to their actual sizes, and the focus is on illustrating the main purpose of the present invention.

[0020] Figure 1 This is a flow chart of the transformer state measurement method based on built-in optical fiber of the present invention.

[0021] Figure 2 Schematic diagram of the structure of a copper bar embedded with optical fiber.

[0022] Figure 3 This is a structural diagram of the optical fiber being arranged inside the outer copper bar.

[0023] Figure 4 This is a schematic diagram of the internal structure of the embedded manufacturing equipment from the front view.

[0024] Figure 5 This is a schematic diagram of the installation structure of the hydraulic inner layer body, hydraulic annulus and hydraulic cylinder.

[0025] Figure 6 This is a schematic diagram of the structure after the hydraulic tubular body is unfolded.

[0026] Figure 7 It is a schematic diagram of the three-dimensional structure of the heating layer body.

[0027] Figure 8 This is a structural diagram of the optical fiber connector assembly being arranged on the transformer casing.

[0028] Figure 9 This is the principle block diagram of the information parameter detection equipment.

[0029] Among them, 1. Copper bar embedded with optical fiber; 101, outer copper bar; 102, optical fiber; 103, inner copper bar; 104, mounting slot; 2. Embedded manufacturing equipment; 21. Top cover; 22. Chassis; 23. Hydraulic outer body; 24. Hydraulic inner body; 25. Heating body; 26. Hydraulic chamber; 27. Molybdenum ribbon resistor; 28. Heating power supply; 29. ​​Hydraulic annulus; 210. Hydraulic tubular body; 211. Second spiral groove; 212. Vacuum system; 213. Vent; 214. Hydraulic cylinder; 215. Oil storage tank; 216. Oil filling motor; 217. Oil filling valve; 218. Oil drain motor; 219. Oil drain valve; 220. Oil filling pipe; 221. Oil drain pipe 3. Fiber optic connector assembly; 31. Casing fiber optic connector; 32. Casing sealing rubber ring; 33. Casing mounting screws; 34. Casing internal fiber optic connector; 35. Casing external fiber optic connector; 4. Transformer casing; 5. Information parameter detection equipment; 51. One-to-two coupler; 52. Distributed optical fiber temperature sensing system; 53. Distributed optical fiber vibration sensing system; 54. Microprocessor. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of 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. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0032] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0033] Furthermore, the terms “first”, “second”, etc. are merely used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0034] Please refer to Figure 1As shown, the present invention provides a transformer state measurement method based on a built-in optical fiber, comprising the following steps: Step 1: manufacture a copper bar 1 embedded with optical fiber; specifically, Figure 2~Figure 3 As shown, the copper bar 1 embedded with the optical fiber includes an outer copper bar 101, an optical fiber 102 and an inner copper bar 103. A mounting groove 104 is provided at the middle position of one end surface of the outer copper bar 101 along its length direction. The optical fiber 102 is adhered in the mounting groove 104 and is completely located inside the mounting groove 104. One end surface of the inner copper bar 103 is pressed onto the end surface of the outer copper bar 101 with the mounting groove 104. One end of the optical fiber 102 is located at one end of the outer copper bar 101 and the inner copper bar 103, and the other end is located at the other end of the outer copper bar 101 and the inner copper bar 103.

[0035] The copper bar 1 embedded with optical fiber is manufactured using the embedding manufacturing device 2; specifically, as Figures 4 to 7 As shown, the embedded manufacturing device 2 includes a top cover 21 and a bottom plate 22 arranged vertically spaced apart. A hydraulic outer layer body 23, a hydraulic inner layer body 24, and a heating layer body 25 having a cylindrical hollow structure with openings at both ends are sealed and detachably arranged between the top cover 21 and the bottom plate 22. The hydraulic outer layer body 23, the hydraulic inner layer body 24, and the heating layer body 25 are coaxially arranged. The hydraulic inner layer body 24 is disposed within the hydraulic outer layer body 23, and the heating layer body 25 is disposed within the hydraulic inner layer body 24. A hydraulic chamber 26 is disposed between the hydraulic outer layer body 23 and the hydraulic inner layer body 24, and the hydraulic chamber 26 is connected to a hydraulic power source located outside the chassis 22. A molybdenum ribbon resistor 27 is spirally wound around the inner circumference of the heating layer body 25, and the molybdenum ribbon resistor 27 is electrically connected to a heating power source 28 outside the chassis 22. A first spiral groove is disposed on the outer circumference of the heating layer body 25 along its height direction. Four hydraulic annular surfaces 29 are provided between the hydraulic inner layer body 25 and the heating layer body 25. The four hydraulic annular surfaces 29 enclose a hydraulic tubular body 210. A second spiral groove 211 is provided on the circumferential outer wall of the hydraulic tubular body 210. The first spiral groove and the second spiral groove 211 are positioned correspondingly. A hydraulic driving member for pushing the four hydraulic annular surfaces 29 toward the heating layer body 25 and communicating with the hydraulic cavity 26 is provided on the circumferential outer wall of the hydraulic inner layer body 24. The top cover is provided with a vacuum system 212, which is connected to the inner space of the heating layer body 25 through two vacuum connecting holes on the top cover. The heating layer body 25 is provided with a vent hole 213; The hydraulic drive unit includes eight hydraulic cylinders 214 connected to the hydraulic chamber. Each hydraulic ring surface 29 is matched with two hydraulic cylinders 214 arranged vertically at intervals. The tail end of each hydraulic cylinder 214 is fixedly connected to the circumferential outer wall of the hydraulic inner layer body 24. The piston rod of each hydraulic cylinder 214 is fixedly connected to the inner wall of the hydraulic ring surface 29. The hydraulic power source is arranged outside the chassis 22 and provides hydraulic power for the eight hydraulic cylinders 214. The hydraulic power source includes an oil storage tank 215, an oil injection motor 216, an oil injection valve 217, An oil drain motor 218, an oil drain valve 219, an oil filling pipe 220 and an oil drain pipe 221; a hydraulic oil inlet hole and a hydraulic oil outlet hole connected to the hydraulic chamber are provided on the chassis; one end of the oil filling pipe 220 and the oil drain pipe 221 are respectively connected to the hydraulic oil inlet hole and the hydraulic oil outlet hole, and the other end of the oil filling pipe 220 and the oil drain pipe 221 are both connected to the oil storage tank 215; the oil filling valve 217 is provided on the oil filling pipe 220, and the oil filling valve 217 is connected to the oil filling motor 216; the oil drain valve 219 is provided on the oil drain pipe 221, and the oil drain valve 219 is connected to the oil drain pipe 221.

[0036] The method for manufacturing a copper bar 1 embedded with optical fibers comprises the following steps: Step 1.1, making two outer copper bars 101 and inner copper bars 103 of equal length; Step 1.2: fabricate an optical fiber 102 having a length greater than that of the outer copper bar 101 and the inner copper bar 103; Step 1.3: Create a mounting groove 104 along the length of the outer copper strip 101 at the middle of one end thereof, and attach the optical fiber 102 to the mounting groove 104, with one end of the optical fiber 102 positioned inside the outer copper strip 101 and the other end positioned outside. Step 1.4: spirally install the outer copper bar 101 in the first spiral groove, and spirally install the inner copper bar 103 in the second spiral groove 211; Step 1.5: Start the vacuum system 212 and the molybdenum ribbon resistor 27. When the temperature of the heating layer body 25 is between 550°C and 600°C, start the hydraulic drive. The piston rods of the multiple hydraulic cylinders 214 push the four hydraulic ring surfaces 29 toward the heating layer body 25 until the inner copper bar 103 is pressed against the outer copper bar 101. The piston rods of the hydraulic cylinders 214 push the hydraulic ring surfaces 29 to a pressure of 15 MPa and maintain it for 3 hours. After that, the outer copper bar 101 is tightly connected to the inner copper bar 103, forming a copper bar 1 embedded with an optical fiber. Step 1.6: Stop pressurization and heating, inject air, open the top cover 21, and remove the copper bar 1 embedded with the optical fiber. Optical fiber 102 is directly embedded in the copper bar and fixed to the copper wire of the winding, forming an integral part of the coil. This allows for more direct and rapid detection of coil state changes, reducing signal loss and interference during transmission and improving monitoring sensitivity. Furthermore, optical fiber exhibits excellent resistance to electromagnetic interference and is unaffected by the strong electromagnetic environment inside the transformer, ensuring the accuracy and stability of the measurement signal. Furthermore, optical fiber's long life and corrosion resistance enable it to operate stably and long-term in harsh environments, enhancing the reliability of the entire monitoring system.

[0037] Step 2: The copper bar 1 embedded with the optical fiber is used as part of the transformer coil, with one end of the copper bar being fixed to the copper bar in the transformer winding coil and the other end being fixed to the connection of the transformer bushing or the connection of the transformer on-load tap changer; Step 3: Install the optical fiber connector assembly 3 on the transformer housing 4, pull one end of the optical fiber 102 embedded in the copper bar 1 to the outside of the copper bar and connect it to the optical fiber connector assembly 3; specifically, Figure 8 As shown, the optical fiber connector assembly 3 includes a housing optical fiber connector 31, a housing sealing rubber ring 32, a housing mounting screw 33, an inner housing optical fiber connector 34 and an outer housing optical fiber connector 35; The housing optical fiber connector 31 is a hollow cylindrical structure. The housing optical fiber connector 31 is transversely arranged on the transformer housing 4. The two ends of the housing optical fiber connector 31 are respectively provided with a housing sealing rubber ring 32 and a housing mounting screw 33. The two ends of the casing optical fiber connector 31 are respectively fixed with an inner casing optical fiber connector 34 and an outer casing optical fiber connector 35; the optical fiber located outside the copper bar is connected to the inner casing optical fiber connector 34, and the information parameter detection device 5 outside the transformer is connected to the outer casing optical fiber connector 35.

[0038] Step 4: Connect the optical fiber connector assembly 3 to the information parameter detection device 5 outside the transformer; specifically, Figure 9 As shown, the information parameter detection device 5 includes a one-to-two coupler 51, a distributed optical fiber temperature sensing system 52, a distributed optical fiber vibration sensing system 53 and a microprocessor 54; The inlet end of the one-to-two coupler 51 is connected to the optical fiber connector 35 outside the casing, and the two outlet ends of the one-to-two coupler 51 are respectively connected in parallel with the distributed optical fiber temperature sensing system 52 and the distributed optical fiber vibration sensing system 53, and the microprocessor 54 is electrically connected to the distributed optical fiber temperature sensing system 52 and the distributed optical fiber vibration sensing system 53.

[0039] Step 5: The information parameter detection device 5 processes the signal transmitted back by the optical fiber in real time, extracts characteristic information reflecting the state of the transformer coil, and the characteristic information of the transformer coil state includes the temperature information and vibration information of the transformer coil, thereby completing the measurement of the transformer coil state.

[0040] The method for measuring the transformer coil state by the information parameter detection device 5 includes the following steps: Step 5.1: The distributed optical fiber temperature sensing system 52 measures the temperature data at different optical fiber locations and transmits the temperature data to the microprocessor 54. The microprocessor 54 records the temperature data as T k , where k=1, 2, 3, 4, 5..., n ,express n The temperature of each measuring point; T k The value indicates the measured temperature. Step 5.2: The distributed optical fiber vibration sensing system 53 collects vibration data at different optical fiber positions and transmits the vibration data to the microprocessor 54. The microprocessor 54 records the vibration data as V ij ; i =1, 2, 3, 4, 5..., m ,express m Vibration of each measuring point; j =1, 2, 3, 4, 5, ..., g , which means g points are sampled each time. Step 5.3, respectively for i =1, 2, 3, 4, 5..., m , for vibration data V ij Perform Fourier transform to get V Fi ; Step 5.4, respectively for i =1, 2, 3, 4, 5..., m ,calculate T k Whether it exceeds the warning threshold T max If more than T max , then the warning, the warning position is i The position corresponding to the value; Step 5.5: i =1, 2, 3, 4, 5..., m , calculate V Fi Whether the amplitude of a certain frequency in exceeds the warning threshold V Fmax-a , a=1, 2, 3, 4, 5..., h , represents the discrete frequency calculated by Fourier transform; if V Fi The amplitude of a certain frequency exceeds the warning threshold V Fmax-a , then the warning, the warning position is i The corresponding position, the warning frequency is a The information parameter detection device 5 can simultaneously monitor the temperature and vibration of the transformer coil via optical fiber 102, providing more comprehensive information for transformer status assessment. Through comprehensive analysis of temperature and vibration, the operating status of the transformer can be more accurately determined, and potential safety hazards can be promptly identified.

[0041] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A transformer state measurement method based on built-in optical fiber, characterized in that: The following steps are involved: Step 1: manufacturing a copper bar embedded with an optical fiber; Step 2: The copper bar embedded with the optical fiber is used as part of the transformer coil, with one end of the copper bar fixed to the copper bar in the transformer winding coil and the other end fixed to the connection of the transformer bushing or the connection of the transformer on-load tap changer; Step 3: Install an optical fiber connector assembly on the transformer housing, pull one end of the optical fiber embedded in the copper bar to the outside of the copper bar and connect it to the optical fiber connector assembly; Step 4: Connect the optical fiber connector assembly to the information parameter detection equipment outside the transformer; Step 5: The information parameter detection device processes the signal transmitted back by the optical fiber in real time, extracts characteristic information reflecting the state of the transformer coil, which includes the temperature information and vibration information of the transformer coil, and completes the measurement of the transformer coil state.

2. The transformer state measurement method based on built-in optical fiber according to claim 1, characterized in that: In step 1, the copper bar embedded with the optical fiber includes an outer copper bar, an optical fiber and an inner copper bar. A mounting groove is provided at the middle position of one end face of the outer copper bar along its length direction. An optical fiber is glued into the mounting groove. The optical fiber is completely located inside the mounting groove. One end face of the inner copper bar is pressed onto the end face of the outer copper bar with the mounting groove. One end of the optical fiber is located at one end of the outer copper bar and the inner copper bar, and the other end is located at the other end of the outer copper bar and the inner copper bar.

3. The transformer state measurement method based on built-in optical fiber according to claim 2, characterized in that: In step 1, a copper bar embedded with optical fibers is manufactured using an embedding manufacturing device; The embedded manufacturing equipment includes a top cover and a bottom plate arranged vertically at intervals, wherein a hydraulic outer layer body, a hydraulic inner layer body, and a heating layer body having cylindrical hollow structures with openings at both ends are sealed and detachably arranged between the top cover and the bottom plate; the hydraulic outer layer body, the hydraulic inner layer body, and the heating layer body are coaxially arranged; The hydraulic inner layer body is disposed within the hydraulic outer layer body, and the heating layer body is disposed within the hydraulic inner layer body; a hydraulic cavity is disposed between the hydraulic outer layer body and the hydraulic inner layer body, and the hydraulic cavity is connected to a hydraulic power source located outside the chassis; a molybdenum ribbon resistor is spirally wound around the inner circumferential surface of the heating layer body, and the molybdenum ribbon resistor is electrically connected to the heating power source outside the chassis; a first spiral groove is disposed on the outer circumferential surface of the heating layer body along its height direction; Four hydraulic annular surfaces are provided between the hydraulic inner layer body and the heating layer body, and the four hydraulic annular surfaces enclose a hydraulic tubular body. A second spiral groove is provided on the circumferential outer wall of the hydraulic tubular body, and the positions of the first spiral groove and the second spiral groove correspond to each other. A hydraulic driving member for pushing the four hydraulic annular surfaces toward the heating layer body and communicating with the hydraulic cavity is provided on the circumferential outer wall of the hydraulic inner layer body; The top cover is provided with a vacuum system, which is connected to the internal space of the heating layer body through two vacuum connecting holes on the top cover, and a vent hole is provided through the heating layer body; The hydraulic drive component includes 8 hydraulic cylinders connected to the hydraulic chamber, each hydraulic ring surface matches two hydraulic cylinders arranged vertically at intervals, the tail end of each hydraulic cylinder is fixedly connected to the circumferential outer wall of the hydraulic inner layer body, and the piston rod of each hydraulic cylinder is fixedly connected to the inner wall of the hydraulic ring surface; the hydraulic power source is arranged on the outside of the chassis and provides hydraulic power for the 8 hydraulic cylinders; the hydraulic power source includes an oil storage tank, an oil filling motor, an oil filling valve, an oil drain motor, an oil drain valve, an oil filling pipe and an oil drain pipe arranged on the outside of the chassis; a hydraulic oil inlet hole and a hydraulic oil outlet hole connected to the hydraulic chamber are opened on the chassis; one end of the oil filling pipe and the oil drain pipe are connected to the hydraulic oil inlet hole and the hydraulic oil outlet hole respectively, and the other end of the oil filling pipe and the oil drain pipe are both connected to the oil storage tank; the oil filling valve is provided on the oil filling pipe, and the oil filling valve is connected to the oil filling motor; the oil drain pipe is provided with the oil drain valve, and the oil drain valve is connected to the oil drain pipe; The method of manufacturing a copper bar embedded with optical fibers comprises the following steps: Step 1.1: Make two outer and inner copper bars of equal length; Step 1.2: Make an optical fiber longer than the outer and inner copper bars Step 1.3: Create a mounting groove along the length of the outer copper strip in the middle of one end. Attach the optical fiber into the groove, with one end inside the outer copper strip and the other end outside. Step 1.4: Install the outer copper bar in a spiral shape in the first spiral groove, and install the inner copper bar in a spiral shape in the second spiral groove; Step 1.5: Start the vacuum system and the molybdenum ribbon resistor. When the temperature of the main heating layer is between 550°C and 600°C, start the hydraulic drive. The piston rods of the multiple hydraulic cylinders push the four hydraulic rings toward the main heating layer until the inner copper bar is pressed against the outer copper bar. After the piston rods of the hydraulic cylinders push the hydraulic rings to a pressure of 15 MPa and maintain it for 3 hours, the outer copper bar and the inner copper bar are tightly connected, forming a copper bar embedded with an optical fiber. Step 1.6: Stop pressurizing and heating, inject air, open the top cover, and remove the copper bar embedded with the optical fiber.

4. The transformer state measurement method based on built-in optical fiber according to claim 3, characterized in that: In step 3 and step 4, the optical fiber connector assembly includes a housing optical fiber connector, a housing sealing rubber ring, a housing mounting screw, an inner housing optical fiber connector, and an outer housing optical fiber connector; The housing optical fiber connector is a hollow cylindrical structure, and the housing optical fiber connector is transversely arranged on the transformer housing, and a housing sealing rubber ring and a housing mounting screw are respectively provided at both ends of the housing optical fiber connector; An inner fiber optic connector and an outer fiber optic connector are fixed at both ends of the casing respectively; the optical fiber outside the copper bar is connected to the inner fiber optic connector, and the information parameter detection equipment outside the transformer is connected to the outer fiber optic connector.

5. The transformer state measurement method based on built-in optical fiber according to claim 4, characterized in that: In step 4, the information parameter detection device includes a one-to-two coupler, a distributed optical fiber temperature sensing system, a distributed optical fiber vibration sensing system and a microprocessor; The inlet end of the one-to-two coupler is connected to the optical fiber connector outside the casing, and the two outlet ends of the one-to-two coupler are respectively connected in parallel with the distributed optical fiber temperature sensing system and the distributed optical fiber vibration sensing system, and the microprocessor is electrically connected to the distributed optical fiber temperature sensing system and the distributed optical fiber vibration sensing system.

6. The transformer state measurement method based on built-in optical fiber according to claim 5, characterized in that: In step 5, the method for measuring the transformer coil state by the information parameter detection device includes the following steps: Step 5.1: The distributed optical fiber temperature sensing system measures the temperature data at different optical fiber locations and transmits the temperature data to the microprocessor, which records the temperature data as T k , where k=1, 2, 3, 4, 5..., n ,express n The temperature of each measuring point; T k The value indicates the measured temperature. Step 5.2: The distributed optical fiber vibration sensing system detects vibration data at different optical fiber positions and transmits the vibration data to the microprocessor, which records the vibration data as V ij ; i =1, 2, 3, 4, 5..., m ,express m Vibration of each measuring point; j =1, 2, 3, 4, 5, ..., g , which means g points are sampled each time. Step 5.3, respectively for i =1, 2, 3, 4, 5..., m , for vibration data V ij Perform Fourier transform to get V Fi ; Step 5.4, respectively for i =1, 2, 3, 4, 5..., m ,calculate T k Whether it exceeds the warning threshold T max If more than T max , then the warning, the warning position is i The position corresponding to the value; Step 5.5: i =1, 2, 3, 4, 5..., m , calculate V Fi Whether the amplitude of a certain frequency in exceeds the warning threshold V Fmax-a , a =1, 2, 3, 4, 5..., h , represents the discrete frequency calculated by Fourier transform; if V Fi The amplitude of a certain frequency exceeds the warning threshold V Fmax-a , then the warning, the warning position is i The corresponding position, the warning frequency is a The corresponding frequency.

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