Measuring structure and measuring method for short-circuit current and electromagnetic field distribution in turn-to-turn short-circuit state of high-voltage winding of single-phase transformer

Abstract

The invention discloses a structure and method for measuring short-circuit current and electromagnetic field distribution in a turn-to-turn short-circuit state of a high-voltage winding of a single-phase transformer, and the structure comprises a plurality of groups of short-circuit notches disposed at the side part of the high-voltage winding, and the short-circuit notches are provided with conductive interface grooves. The conductive interface groove is matched with a conductive protrusion arranged at the bottom of a rigid conductive strip, the top of the rigid conductive strip penetrates through the short-circuit wiring measuring disc and is limited through a clamping device, the top of the rigid conductive strip is connected with a switching binding post through a detachable connecting wire, and the switching binding post is connected with a short-circuit current measuring device through a measuring wire. An electromagnetic field inductive probe is arranged on the outer side of the high-voltage winding; the transformer turn-to-turn short circuit state can be simulated and measured, comprehensive and complete state data are obtained, and powerful data support is provided for analysis and identification of characteristic signals.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic field measurement technology, and in particular to a measurement structure and method for measuring short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions in the high-voltage winding of a single-phase transformer. Background Technology

[0002] Modern power systems are vast and complex, encompassing numerous power generation, transmission, transformation, distribution, and consumption stages. Transformers, as key equipment connecting various voltage levels, are numerous and widely distributed. In such a massive system, a short-circuit fault in any transformer can trigger a chain reaction, affecting the normal operation of the system. Simultaneously, with socio-economic development and rising living standards, various industries have increasingly higher demands for the reliability and stability of power supply. Power outages can cause significant economic losses to industrial production, such as factory shutdowns and equipment damage; they also cause considerable inconvenience to residents, affecting lighting, communication, and transportation. Therefore, real-time monitoring and fault diagnosis of transformers are necessary, with short-circuit current measurement being a crucial method to ensure reliable power supply. However, early-stage short-circuit faults are often insidious and may not immediately cause complete transformer damage, but they gradually affect the transformer's performance and lifespan. If not detected and addressed promptly, the short circuit will worsen, eventually leading to transformer burnout or even more serious power accidents. Therefore, simulating and measuring the inter-turn short circuit state of a transformer to obtain a large number of data samples for analysis and determination of fault characteristic signals is of great significance for real-time monitoring of transformer operating status and fault early warning. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned shortcomings and provide a measurement structure and method for the distribution of short-circuit current and electromagnetic field in the inter-turn short-circuit state of a single-phase transformer high-voltage winding. This method simulates and measures the inter-turn short-circuit state of the transformer to obtain comprehensive and complete state data, providing strong data support for the analysis and identification of characteristic signals.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding includes multiple sets of short-circuit cuts on the side of the high-voltage winding. Conductive interface slots are installed at the short-circuit cut locations. These slots engage with conductive protrusions at the bottom of a rigid conductive strip. The top of the rigid conductive strip passes through a short-circuit connection measuring disc and is limited by a clamping device. The top of the rigid conductive strip is connected to a transfer terminal via a detachable connecting wire. The transfer terminal is connected to a short-circuit current measuring device via a measuring wire. An electromagnetic field induction probe is located on the outside of the high-voltage winding.

[0005] Preferably, an insulating sleeve is also fitted on the outside of the rigid conductive strip. The insulating sleeve is vertically installed inside the high-voltage winding, and a through hole is opened on the side of the insulating sleeve to cooperate with the conductive protrusion.

[0006] Preferably, the rigid conductive strip is further provided with a scale on its surface, and an indicator plate is provided on one side of the top of the insulating sleeve.

[0007] Preferably, the clamping device includes a fixing clip, which slides in a groove on the surface of the short-circuit wiring measuring disc via a sliding rod, and the clamping pole at the bottom of the fixing clip engages with the clamping pole groove on the surface of the short-circuit wiring measuring disc.

[0008] Preferably, the circuit containing the measuring wire is further provided with an adjustable resistance box and an adjustable capacitor box.

[0009] Preferably, the short-circuit current measuring device includes a housing, inside which is an ammeter. The ammeter is connected to the two poles of a rotary connector via current test leads, and the terminals of the rotary connector are connected to the measuring leads.

[0010] Preferably, the rotary connector includes two arc-shaped conductive transition rails, which are respectively connected to the ends of the two current test leads of the ammeter. The conductive transition rails are slidably engaged with the bottom of a vertically arranged axial conductive transition rod. The axial conductive transition rod is fixedly mounted on the outside of the rotary insulating support frame. The rotary insulating support frame has multiple parallel radial conductive spokes arranged sequentially from top to bottom. The axial conductive transition rod has multiple first connecting convex poles arranged from top to bottom. The radial conductive spokes have multiple second connecting convex poles arranged on their outer periphery. Both the first and second connecting convex poles are engaged with the connection ports at the ends of the measuring leads.

[0011] Preferably, the rotating insulating support frame includes a knob at the top, the bottom of which is fixedly connected to the top of the mounting post. The mounting post is fixedly provided with multiple parallel insulating discs from top to bottom. A radial conductive spoke is installed between each two adjacent insulating discs. Each insulating disc has mounting holes on both sides for inserting an axial conductive adapter rod. The bottom of the mounting post is rotatably connected to the bottom of the encapsulation shell.

[0012] Preferably, the radial conductive spokes include a left conductive spoke and a right conductive spoke that are symmetrically arranged and connected to each other, and the number of second connecting convex poles on the left conductive spoke, the right conductive spoke, and the radial conductive spokes are all the same.

[0013] Preferably, the radial conductive spokes have a slot in the middle region for inserting the mounting post, and each left and right conductive spoke has a second connecting convex pole at its outer end.

[0014] Preferably, the connection ports at the ends of the multiple measuring wires are arranged in a stepped manner, surrounding the second connecting convex poles of the multiple radial conductive spokes from top to bottom.

[0015] Preferably, the top of the enclosure is provided with a gear position indicator near the knob, and the short-circuit wiring measuring plate is provided with a wiring number near the corresponding adapter terminal, and the gear position indicator and the wiring number correspond to each other.

[0016] Preferably, the electromagnetic field sensing probe is mounted on a sensor mounting column.

[0017] In addition, the present invention also discloses a measurement method for the measurement structure of short-circuit current and electromagnetic field distribution under the inter-turn short-circuit state of the high-voltage winding of the above-mentioned single-phase transformer, which includes the following steps: S1. Take a rigid conductive strip and insert it into the insulating bushing inside the high-voltage winding from top to bottom. When the conductive protrusion at its bottom reaches the position to be measured, rotate the rigid conductive strip so that the conductive protrusion aligns with the through hole on the side of the insulating bushing and protrudes from it into the conductive interface groove installed at the short-circuit cut position, thereby making the rigid conductive strip connected to the short-circuit cut of the high-voltage winding; then, use a clamping device to limit the top of the rigid conductive strip to the short-circuit connection measuring plate. S2. Take another rigid conductive strip and insert it from top to bottom into another insulating sleeve inside the high-voltage winding. When the conductive protrusion at its bottom reaches the position to be measured, rotate the rigid conductive strip so that the conductive protrusion is aligned with the through hole on the side of the insulating sleeve and protrudes from it into the conductive interface groove installed at the short-circuit cut position, thereby making the rigid conductive strip connected to the short-circuit cut of the high-voltage winding. Then, the top of the rigid conductive strip is limited to the short-circuit wiring measuring plate by the clamping device. S3. Connect the tops of the two rigid conductive strips to the other two corresponding adapter terminals using connecting wires; then open the rotating connection device of the short-circuit current measuring device so that the ammeter is connected to the circuit where the measuring wire is located. S4. The current coming out from one of the short-circuit cuts in the high-voltage winding passes through the conductive protrusion, the rigid conductive strip and the connecting wire in sequence, and then enters one end of the measuring wire from one of the adapter terminals. It then enters the ammeter through one side of the rotary connector. The ammeter can display the intensity of the short-circuit current. The current coming out from the ammeter enters the measuring wire from the other side of the rotary connector, and then enters another adapter terminal from the other end of the measuring wire. The current then passes through another connecting wire, the rigid conductive strip and the conductive protrusion in sequence, and finally returns to the high-voltage winding from another short-circuit cut. S5. In the above process, the magnitude of the short-circuit current under the complete short-circuit condition can be measured by an ammeter, and the electromagnetic field distribution under the short-circuit condition can be measured by an electromagnetic field induction probe, and the measurement data can be recorded.

[0018] Further, step S3 specifically involves: connecting the tops of the two rigid conductive strips to two other corresponding adapter terminals via connecting wires; then opening the rotating wiring device of the short-circuit current measuring device so that the knob is turned into a position indicating the position and the wiring number, thereby connecting the ammeter to the circuit where the measuring wire is located.

[0019] Further, in step S4, the specific process of the current entering the ammeter from one side of the rotary connector and then exiting the ammeter to enter the other side of the rotary connector is as follows: the current sequentially passes through the connection port of the measuring wire on one side, the first connecting salient pole, and the axial conductive adapter rod, then enters the current test line on one side from the bottom conductive adapter rail, then passes through the ammeter, exits from the current test line on the other side, then sequentially passes through the conductive adapter rail, the axial conductive adapter rod, and the first connecting salient pole on the other side, and exits from the connection port of the measuring wire on the other side.

[0020] Furthermore, it also includes the following steps: S6. By adjusting the adjustable resistance box and adjustable capacitor box set on the circuit where the measuring wire is located, the stepless short circuit condition simulation measurement of the circuit where the two short circuit cuts of the high voltage winding are located from insulation to complete short circuit and the simulation measurement under the condition of capacitance can be realized.

[0021] Furthermore, it also includes the following steps: S7. By adjusting the height of the two rigid conductive strips or re-inserting the rigid conductive strips into the insulating sleeves at the other two positions, and then repeating steps S3, S4, and S5, the magnitude of the short-circuit current under a complete short-circuit condition at different positions of the high-voltage winding can be measured. The electromagnetic field distribution under the short-circuit condition can also be measured using an electromagnetic field induction probe, and the measurement data can be recorded.

[0022] Beneficial effects of this invention: 1. This invention employs a measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions in the high-voltage winding of a single-phase transformer. An opening is made in the high-voltage winding of the prototype, and an insulating bushing integrated with the winding is fabricated at the opening. The short-circuit current is led out and measured via a rigid conductive strip connected to the winding. This allows for short-circuit simulation and measurement of short-circuit current between any turns of the winding, obtaining comprehensive and complete state data, providing strong data support for the analysis and identification of characteristic signals.

[0023] 2. This invention uses rigid conductive strips to draw out short-circuit current while simultaneously constructing variable resistance and capacitance boxes externally. After connection, the size of the connected resistance and capacitance can be adjusted to simulate the aging and damage degree of winding insulation. It can obtain the distribution and magnitude of current under different short-circuit degrees between winding turns, providing reliable data indicators for the identification of fault degree and range, thereby providing early warning of inter-turn short-circuit faults and improving the safety and stability of power operation.

[0024] 3. This invention installs an electromagnetic sensor on the high-voltage winding. When simulating an inter-turn short circuit, it can measure the distribution and magnitude of the electromagnetic field under different conditions, serving as an auxiliary identification feature for inter-turn short circuit faults. This allows for more accurate detection of the transformer's fault degree and location of the fault. Attached Figure Description

[0025] Figure 1 This is a three-dimensional structural diagram of a measurement structure for the distribution of short-circuit current and electromagnetic field in the high-voltage winding of a single-phase transformer under inter-turn short-circuit conditions. Figure 2 A schematic diagram of a structure for creating a short-circuit cut in the high-voltage winding; Figure 3 This is a schematic diagram of the conductive interface groove. Figure 4 This is a schematic diagram of the structure for installing an insulating bushing inside a high-voltage winding. Figure 5 This is a schematic diagram of a rigid conductive strip installed inside an insulating sleeve. Figure 6 This is a schematic diagram of the rigid conductive strip. Figure 7 This is a schematic diagram of the insulating sleeve. Figure 8 A top view of the installation of components such as the clamping device, adapter terminal, measuring wire, and short-circuit current measuring device on the short-circuit connection measuring panel; Figure 9 for Figure 8 An enlarged structural diagram of the area where the clamping device is located; Figure 10 for Figure 9 A three-dimensional structural diagram of the fixing clip; Figure 11 for Figure 8 A schematic diagram of the structure after removing the packaging shell; Figure 12 for Figure 11 An enlarged structural diagram of the area where the rotary wiring device is located; Figure 13 for Figure 12 A schematic diagram of the three-dimensional structure from another perspective; Figure 14 for Figure 13 A three-dimensional structural diagram of the radial conductive spokes; Figure 15 for Figure 13 A three-dimensional structural diagram of the central axial conductive adapter rod; Figure 16 for Figure 13 A three-dimensional structural diagram of the rotating insulating support frame; Figure 17 for Figure 13 A schematic diagram of the structure in which the ammeter is connected to the conductive transfer rail of the rotary connector via the current test leads. Figure 18 for Figure 8 A schematic diagram of the enclosure of the short-circuit current measuring device; Figure 19 for Figure 13 A magnified schematic diagram of the end of the measuring wire; Figure 20 This is a schematic diagram of the installation structure of an electromagnetic field induction probe. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0027] Example 1: As Figure 1-19 As shown, a measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding includes multiple sets of short-circuit cuts 2 opened on the side of the high-voltage winding 1. Conductive interface grooves 3 are installed at the positions of the short-circuit cuts 2. The conductive interface grooves 3 cooperate with the conductive protrusions 5 provided at the bottom of the rigid conductive strip 4. The top of the rigid conductive strip 4 passes through the short-circuit connection measuring disk 7 and is limited by the clamping device 8. The top of the rigid conductive strip 4 is connected to the adapter terminal 10 through a detachable connecting wire 9. The adapter terminal 10 is connected to the short-circuit current measuring device 6 through a measuring wire 11. An electromagnetic field induction probe 13 is provided on the outside of the high-voltage winding 1.

[0028] like Figure 4 , 5 As shown in Figures 6 and 7, an insulating sleeve 12 is also fitted around the outside of the rigid conductive strip 4. The insulating sleeve 12 is vertically installed inside the high-voltage winding 1, and a through hole 14 is provided on the side of the insulating sleeve 12 to cooperate with the conductive protrusion 5. By setting the insulating sleeve 12, the surface of the rigid conductive strip 4 can be prevented from accidentally contacting other conductive interface grooves 3, thereby affecting the accuracy of the measurement results.

[0029] The rigid conductive strip 4 is also provided with a scale 15 on its surface, and an indicator plate 16 is provided on one side of the top of the insulating sleeve 12. By cooperating with the scale 15, the depth to which the rigid conductive strip 4 needs to be inserted into the insulating sleeve 12 can be clearly determined when the rigid conductive strip 4 is inserted into the insulating sleeve 12, ensuring that the conductive protrusion 5 at the bottom of the rigid conductive strip 4 can accurately align with the short-circuit cut 2 to be tested.

[0030] like Figure 8 , 9 As shown in Figure 10, the clamping device 8 includes a fixing clip 8.1. The fixing clip 8.1 is slidably engaged with a sliding groove 8.3 on the surface of the short-circuit wiring measuring disk 7 via a sliding rod 8.2. The clamping pole 8.4 at the bottom of the fixing clip 8.1 engages with a clamping pole groove 8.5 on the surface of the short-circuit wiring measuring disk 7. In this embodiment, when the top of the rigid conductive strip 4 extends into the short-circuit wiring measuring disk 7, the fixing clip 8.1 can move through the sliding engagement of the sliding rod 8.2 and the sliding groove 8.3, thereby clamping the rigid conductive strip 4 from the side. When the clamping pole 8.4 enters the clamping pole groove 8.5, the fixing clip 8.1 can completely limit the rigid conductive strip 4. In this embodiment, a fixed stop is provided on the opposite side of the fixing clip 8.1, so that when the fixing clip 8.1 moves, it can compress the rigid conductive strip 4.

[0031] like Figure 8 As shown, the circuit containing the measuring lead 11 is also equipped with an adjustable resistance box 17 and an adjustable capacitor box 18. In this embodiment, by adjusting the adjustable resistance box 17 and the adjustable capacitor box 18 on the circuit containing the measuring lead 11, it is possible to simulate and measure the stepless short circuit condition from insulation to complete short circuit in the circuit containing the two short circuit cuts of the high voltage winding, as well as the simulation measurement under the condition of capacitance. In this way, the aging and damage degree of the winding insulation can be simulated.

[0032] like Figures 11 to 19 As shown, the short-circuit current measuring device 6 includes a housing 6.1, inside which is an ammeter 6.4. The ammeter 6.4 is connected to the two poles of a rotary connector 6.2 via a current test lead 6.3. The terminals of the rotary connector 6.2 are connected to the measuring lead 11.

[0033] The rotary connector 6.2 includes two arc-shaped conductive transition rails 6.2.1, which are respectively connected to the ends of the two current test leads 6.3 of the ammeter 6.4. The conductive transition rails 6.2.1 are slidably engaged with the bottom of the vertically arranged axial conductive transition rod 6.2.2. The axial conductive transition rod 6.2.2 is fixedly mounted on the outside of the rotary insulating support frame 6.2.3. The rotary insulating support frame 6.2.3 has multiple parallel radial conductive spokes 6.2.4 arranged sequentially from top to bottom. The axial conductive transition rod 6.2.2 has multiple first connecting convex poles 6.2.5 arranged from top to bottom. The radial conductive spokes 6.2.4 have multiple second connecting convex poles 6.2.6 arranged on their outer periphery. Both the first connecting convex poles 6.2.5 and the second connecting convex poles 6.2.6 are engaged with the connection port 11.1 at the end of the measuring lead 11.

[0034] like Figure 16 As shown, the rotating insulating support frame 6.2.3 includes a knob 6.2.3.1 located at the top. The bottom of the knob 6.2.3.1 is fixedly connected to the top of the mounting post 6.2.3.2. The mounting post 6.2.3.2 has multiple parallel insulating discs 6.2.3.3 fixedly arranged from top to bottom. A radial conductive spoke 6.2.4 is installed between each pair of adjacent insulating discs 6.2.3.3. Each insulating disc 6.2.3.3 has mounting holes 6.2.3.4 on both sides for inserting axial conductive adapter rods 6.2.2. The bottom of the mounting post 6.2.3.2 is rotatably connected to the bottom of the encapsulation shell 6.1.

[0035] like Figure 14 As shown, the radial conductive spokes 6.2.4 include a left conductive spoke and a right conductive spoke that are symmetrically arranged and connected to each other. The number of second connecting convex poles 6.2.6 on the left conductive spokes, the right conductive spokes, and the radial conductive spokes 6.2.4 are all the same.

[0036] The radial conductive spokes 6.2.4 have a slot in the middle region for mounting the post 6.2.3.2, and each left and right conductive spoke has a second connecting convex pole 6.2.6 at its outer end.

[0037] like Figure 19 As shown, the connection ports 11.1 at the ends of multiple measuring wires 11 are arranged in a stepped manner around the second connecting convex poles 6.2.6 of multiple radial conductive spokes 6.2.4 from top to bottom.

[0038] In the above technical solution, each rotation of knob 6.2.3.1 causes the entire rotating insulating support frame 6.2.3 to rotate, thereby allowing the axial conductive adapter rod 6.2.2 to enter the conductive adapter rail 6.2.1 and slide into it (in the initial state, when knob 6.2.3.1 is in the 0-0 position, the axial conductive adapter rod 6.2.2 and the conductive adapter rail 6.2.1 are separated). The radial conductive spokes 6.2.4 also rotate accordingly. When knob 6.2.3.1 is rotated to the corresponding position, one of the first connecting convex poles 6.2.5 of the two axial conductive adapter rods 6.2.2 respectively mates with the connection port 11.1 at the end of the corresponding measuring wire 11 on both sides. The two opposite second connecting convex poles 6.2.6 of each radial conductive spoke 6.2.4 respectively mate with the connection port 11.1 at the end of the other corresponding measuring wires 11 on both sides.

[0039] like Figure 18 As shown, the top of the encapsulation housing 6.1, near the knob 6.2.3.1, has a position indicator value 6.2.7, and the short-circuit wiring measuring dial 7, near the corresponding adapter terminal 10, has a wiring number 10.1. The position indicator value 6.2.7 and the wiring number 10.1 correspond to each other. By setting the position indicator value 6.2.7 and the wiring number 10.1, the position of the knob 6.2.3.1 can be easily and accurately adjusted, facilitating accurate recording of the measurement process.

[0040] like Figure 20 As shown, the electromagnetic field induction probe 13 is mounted on the sensor mounting column 19. In this embodiment, three electromagnetic field induction probes 13 can be installed on the short-circuit side and the opposite side, respectively located at the upper end, middle and lower end of the outer side of the winding. When simulating inter-turn short circuit conditions, the electromagnetic field distribution and magnitude under different conditions can be measured, serving as an auxiliary identification feature for inter-turn short circuit faults, more accurately detecting the degree of transformer faults and locating the fault location of the transformer.

[0041] Example 2: The present invention also discloses a measurement method for the measurement structure of the short-circuit current and electromagnetic field distribution of the high-voltage winding of the above-mentioned single-phase transformer under the condition of inter-turn short circuit, which includes the following steps: S1. Take a rigid conductive strip 4 and insert it from top to bottom into the insulating sleeve 12 inside the high voltage winding 1. When the conductive protrusion 5 at its bottom reaches the position to be measured, rotate the rigid conductive strip 4 so that the conductive protrusion 5 is aligned with the through hole 14 on the side of the insulating sleeve 12 and protrudes from it to enter the conductive interface groove 3 installed at the short circuit cut 2 position, thereby making the rigid conductive strip 4 connected to the short circuit cut 2 of the high voltage winding 1; then the top of the rigid conductive strip 4 is limited on the short circuit connection measuring plate 7 by the clamping device 8. S2. Take another rigid conductive strip 4 and insert it from top to bottom into another insulating sleeve 12 inside the high voltage winding 1. When the conductive protrusion 5 at its bottom reaches the position to be measured, rotate the rigid conductive strip 4 so that the conductive protrusion 5 is aligned with the through hole 14 on the side of the insulating sleeve 12 and protrudes from it to enter the conductive interface groove 3 installed at the short circuit cut 2 position, thereby making the rigid conductive strip 4 connected to the short circuit cut 2 of the high voltage winding 1; then the top of the rigid conductive strip 4 is limited to the short circuit connection measuring plate 7 by the clamping device 8. S3. Connect the tops of the two rigid conductive strips 4 to the other two corresponding adapter terminals 10 via connecting wires 9; then open the rotating wiring device 6.2 of the short-circuit current measuring device 6 so that the ammeter 6.4 is connected to the circuit where the measuring wire 11 is located. S4. The current coming out of one of the short-circuit cuts 2 of the high-voltage winding 1 passes sequentially through the conductive protrusion 5, the rigid conductive strip 4 and the connecting wire 9, and then enters one end of the measuring wire 11 through a transition terminal 10. It then passes through one side of the rotary connector 6.2 and enters the ammeter 6.4. The ammeter 6.4 can display the intensity of the short-circuit current. The current coming out of the ammeter 6.4 enters the measuring wire 11 from the other side of the rotary connector 6.2, and enters another transition terminal 10 from the other end of the measuring wire 11. Then the current passes sequentially through another connecting wire 9, the rigid conductive strip 4 and the conductive protrusion 5, and finally returns to the high-voltage winding 1 from another short-circuit cut 2. As current flows from one side of the rotary connector 6.2 into the ammeter 6.4 and then out of the ammeter 6.4 into the other side of the rotary connector 6.2, the current sequentially passes through the connection port 11.1 of one side of the measuring wire 11, the first connecting salient pole 6.2.5, and the axial conductive adapter rod 6.2.2. Then, it enters the current test wire 6.3 on one side from the bottom conductive adapter rail 6.2.1. After passing through the ammeter 6.4, it exits from the current test wire 6.3 on the other side, and then sequentially passes through the conductive adapter rail 6.2.1, the axial conductive adapter rod 6.2.2, and the first connecting salient pole 6.2.5 on the other side, and exits from the connection port 11.1 of the measuring wire 11 on the other side.

[0042] The first connecting salient 6.2.5 of the axial conductive adapter rod 6.2.2 is respectively connected to the end of a corresponding measuring wire 11 on both sides. S5. During the above process, the magnitude of the short-circuit current under the complete short-circuit condition can be measured by ammeter 6.4, and the electromagnetic field distribution under the short-circuit condition can be measured by electromagnetic field induction probe 13, and the measurement data can be recorded.

[0043] Further, step S3 specifically involves: connecting the tops of the two rigid conductive strips 4 to the other two corresponding adapter terminals 10 with wiring number 10.1 via connecting wires 9; then opening the rotary wiring device 6.2 of the short-circuit current measuring device 6 so that the setting indication value 6.2.7 of its knob 6.2.3.1 corresponds to wiring number 10.1, thereby connecting the ammeter 6.4 to the circuit where the measuring wire 11 is located.

[0044] For example, in this embodiment, the first rigid conductive strip is connected to the adapter terminal with wiring number 1 via a connecting wire, and the second rigid conductive strip is connected to the adapter terminal with wiring number 2 via a connecting wire. Then, the knob is turned to the position with the gear indicator value of 1-2. At this time, the magnitude of the short-circuit current introduced by the first and second rigid conductive strips can be measured by the ammeter 6.4.

[0045] Similarly, connect the second rigid conductive strip to the adapter terminal numbered 2 via a connecting wire, and connect the third rigid conductive strip to the adapter terminal numbered 3 via a connecting wire. Then turn the knob to the position indicated by 2-3. At this point, the magnitude of the short-circuit current introduced by the second and third rigid conductive strips can be measured using ammeter 6.4.

[0046] It should be noted that, in order to facilitate the measurement of short-circuit current between different numbers (e.g., wiring numbers 1 and 3, 1 and 4, etc.), the measuring leads can be designed as a continuous S-shaped loop that repeatedly passes through the adjustable resistance box 17, the adjustable capacitor box 18, and the rotating connection device 6.2. The following example illustrates this: If the first rigid conductive strip is connected to the adapter terminal with wiring number 1 via a connecting wire, and the third rigid conductive strip is connected to the adapter terminal with wiring number 3 via a connecting wire, and then the knob is turned to the position indicating 1-2 or 2-3, the magnitude of the short-circuit current introduced by the first and third rigid conductive strips can be measured by the ammeter 6.4. To explain the current flow in detail: For example, the current coming from one of the short-circuit cuts in the high-voltage winding passes sequentially through the conductive protrusion, the rigid conductive strip, and the connecting wire. Then, it enters the right-side measuring wire end through the adapter terminal numbered 1, and then passes through the first right-side measuring wire (the first one from bottom to top) through the right side of the rotary connector into the ammeter. The current from the ammeter enters the first left-side measuring wire (the first one from bottom to top) from the left side of the rotary connector. Since the first left-side measuring wire is not directly connected to the adapter terminal numbered 3, the current then flows through the second left-side measuring wire (from bottom to top)... Returning from the second connection point, the ammeter passes through the left side of the rotating connector and enters the second connecting salient 6.2.6 on the left side via the left connection port 11.1. It then enters the second connecting salient 6.2.6 on the right side via the radial conductive spoke 6.2.4. From the right connection port 11.1, it enters the second measuring wire on the right side (second from the bottom). It then returns to the adapter terminal with connection number 3, and finally passes through the connecting wire, rigid conductive strip, and conductive protrusion to return to another short-circuit cut. This allows the ammeter 6.4 to measure the short-circuit current introduced by the first and third rigid conductive strips.

[0047] Furthermore, it also includes the following steps: S6. By adjusting the adjustable resistor box 17 and adjustable capacitor box 18 set on the circuit where the measuring wire 11 is located, the simulation measurement of the stepless short circuit condition from insulation to complete short circuit in the circuit where the two short circuit cuts 2 of the high voltage winding 1 are located is realized, as well as the simulation measurement under the condition of presence of capacitance.

[0048] Furthermore, it also includes the following steps: S7. By adjusting the height of the two rigid conductive strips 4 or re-inserting the rigid conductive strips 4 into the insulating sleeves 12 at the other two positions, and then repeating steps S3, S4, and S5, the magnitude of the short-circuit current under the complete short-circuit condition at different positions of the high-voltage winding 1 can be measured. The electromagnetic field distribution under the short-circuit condition can also be measured through the electromagnetic field induction probe 13, and the measurement data can be recorded.

[0049] The above embodiments are merely preferred technical solutions of the present invention and should not be considered as limitations on the present invention. The scope of protection of the present invention should be limited to the technical solutions described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding, comprising multiple sets of short-circuit cuts (2) opened on the side of the high-voltage winding (1), wherein conductive interface grooves (3) are installed at the positions of the short-circuit cuts (2), characterized in that: The conductive interface groove (3) cooperates with the conductive protrusion (5) at the bottom of the rigid conductive strip (4). The top of the rigid conductive strip (4) passes through the short-circuit wiring measuring disk (7) and is limited by the clamping device (8). The top of the rigid conductive strip (4) is connected to the adapter terminal (10) through a detachable connecting wire (9). The adapter terminal (10) is connected to the short-circuit current measuring device (6) through a measuring wire (11). An electromagnetic field induction probe (13) is provided on the outside of the high-voltage winding (1).

2. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 1, characterized in that: An insulating sleeve (12) is also fitted on the outside of the rigid conductive strip (4). The insulating sleeve (12) is vertically installed inside the high voltage winding (1). A through hole (14) is opened on the side of the insulating sleeve (12) to cooperate with the conductive protrusion (5).

3. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 2, characterized in that: The rigid conductive strip (4) is also provided with a scale (15) on its surface, and a position plate (16) is provided on one side of the top of the insulating sleeve (12).

4. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 1, characterized in that: The clamping device (8) includes a fixing clip (8.1), which slides in cooperation with the sliding groove (8.3) on the surface of the short-circuit wiring measuring plate (7) via a slide rod (8.2), and the clamping pole (8.4) at the bottom of the fixing clip (8.1) cooperates with the clamping pole groove (8.5) on the surface of the short-circuit wiring measuring plate (7).

5. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 1, characterized in that: The circuit containing the measuring lead (11) is also equipped with an adjustable resistance box (17) and an adjustable capacitor box (18).

6. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 1, characterized in that: The short-circuit current measuring device (6) includes a housing (6.1), inside which is provided an ammeter (6.4). The ammeter (6.4) is connected to the two poles of a rotary connector (6.2) via a current test lead (6.3). The terminals of the rotary connector (6.2) are connected to the measuring lead (11).

7. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 6, characterized in that: The rotary wiring device (6.2) includes two arc-shaped conductive transition rails (6.2.1), which are respectively connected to the ends of the two current test leads (6.3) of the ammeter (6.4). The conductive transition rails (6.2.1) are slidably engaged with the bottom of a vertically arranged axial conductive transition rod (6.2.2). The axial conductive transition rod (6.2.2) is fixedly mounted on the outside of the rotary insulating support frame (6.2.3). The edge support frame (6.2.3) is provided with multiple radial conductive spokes (6.2.4) that are parallel to each other from top to bottom. The axial conductive adapter rod (6.2.2) is provided with multiple first connecting convex poles (6.2.5) from top to bottom. The radial conductive spokes (6.2.4) are provided with multiple second connecting convex poles (6.2.6) on their outer periphery. The first connecting convex poles (6.2.5) and the second connecting convex poles (6.2.6) are both matched with the connection port (11.1) at the end of the measuring wire (11).

8. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 7, characterized in that: The rotating insulating support frame (6.2.3) includes a knob (6.2.3.1) located at the top. The bottom of the knob (6.2.3.1) is fixedly connected to the top of the mounting post (6.2.3.2). The mounting post (6.2.3.2) is fixedly provided with multiple parallel insulating discs from top to bottom. 6.2.3.3), a radial conductive spoke (6.2.4) is installed between each two adjacent insulating discs (6.2.3.3). Each insulating disc (6.2.3.3) has mounting holes (6.2.3.4) on both sides for inserting the axial conductive adapter rod (6.2.2). The bottom of the mounting post (6.2.3.2) is rotatably connected to the bottom of the encapsulation shell (6.1).

9. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 8, characterized in that: The radial conductive spokes (6.2.4) include a left conductive spoke and a right conductive spoke that are symmetrically arranged and connected to each other. The number of second connecting convex poles (6.2.6) on the left conductive spokes, the right conductive spokes and the radial conductive spokes (6.2.4) are all the same.

10. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 9, characterized in that: The radial conductive spoke (6.2.4) has a slot in the middle region for inserting the mounting post (6.2.3.2), and each left and right conductive spoke has a second connecting convex pole (6.2.6) at its outer end.

11. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 9, characterized in that: The connection ports (11.1) at the ends of multiple measuring wires (11) are arranged in a stepped manner around the second connecting convex poles (6.2.6) of multiple radial conductive spokes (6.2.4) from top to bottom.

12. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 8, characterized in that: The top of the encapsulation housing (6.1) near the knob (6.2.3.1) is provided with a gear position indicator (6.2.7), and the short-circuit wiring measuring plate (7) near the corresponding adapter terminal (10) is provided with a wiring number (10.1). The gear position indicator (6.2.7) and the wiring number (10.1) correspond to each other.

13. The measurement structure for short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 1, characterized in that: The electromagnetic field induction probe (13) is mounted on the sensor mounting column (19).

14. A measurement method for a measurement structure of short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions in the high-voltage winding of a single-phase transformer, characterized in that: It includes the following steps: S1. Take a rigid conductive strip (4) and insert it from top to bottom into the insulating sleeve (12) inside the high voltage winding (1). When the conductive protrusion (5) at its bottom reaches the position to be measured, rotate the rigid conductive strip (4) so ​​that the conductive protrusion (5) is aligned with the through hole (14) on the side of the insulating sleeve (12) and protrudes from it to enter the conductive interface groove (3) installed at the short circuit cut (2) position, so that the rigid conductive strip (4) is connected to the short circuit cut (2) of the high voltage winding (1); then the top of the rigid conductive strip (4) is limited to the short circuit connection measuring plate (7) by the clamping device (8); S2. Take another rigid conductive strip (4) and insert it from top to bottom into another insulating sleeve (12) inside the high voltage winding (1). When the conductive protrusion (5) at its bottom reaches the position to be measured, rotate the rigid conductive strip (4) so ​​that the conductive protrusion (5) is aligned with the through hole (14) on the side of the insulating sleeve (12) and protrudes from it to enter the conductive interface groove (3) installed at the short circuit cut (2) position, so that the rigid conductive strip (4) is connected to the short circuit cut (2) of the high voltage winding (1); then the top of the rigid conductive strip (4) is limited to the short circuit connection measuring plate (7) by the clamping device (8); S3. Connect the tops of the two rigid conductive strips (4) to the other two corresponding adapter terminals (10) via connecting wires (9); then open the rotating wiring device (6.2) of the short-circuit current measuring device (6) so that the ammeter (6.4) is connected to the circuit where the measuring wire (11) is located. S4. The current coming out of one of the short-circuit cuts (2) of the high-voltage winding (1) passes through the conductive protrusion (5), the rigid conductive strip (4) and the connecting wire (9) in sequence, and then enters one end of the measuring wire (11) through a transition terminal (10), and then enters the ammeter (6.4) through one side of the rotary connector (6.2). The ammeter (6.4) can display the intensity of the short-circuit current. The current coming out of the ammeter (6.4) enters the measuring wire (11) from the other side of the rotary connector (6.2), and enters another transition terminal (10) from the other end of the measuring wire (11). Then the current passes through another connecting wire (9), the rigid conductive strip (4) and the conductive protrusion (5) in sequence, and finally returns to the high-voltage winding (1) from another short-circuit cut (2). S5. In the above process, the magnitude of the short-circuit current under the complete short-circuit condition can be measured by the ammeter (6.4), and the electromagnetic field distribution under the short-circuit condition can be measured by the electromagnetic field induction probe (13), and the measurement data can be recorded.

15. The measurement method for the measurement structure of short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 14, characterized in that: The specific steps of step S3 are as follows: connect the tops of the two rigid conductive strips (4) to the two corresponding adapter terminals (10) of the other two wiring numbers (10.1) through the connecting wires (9); then open the rotating wiring device (6.2) of the short-circuit current measuring device (6) so that the range indication value (6.2.7) of its knob (6.2.3.1) corresponds to the wiring number (10.1), thereby connecting the ammeter (6.4) to the circuit where the measuring wire (11) is located.

16. The measurement method for the measurement structure of short-circuit current and electromagnetic field distribution of a single-phase transformer high-voltage winding under inter-turn short-circuit conditions as described in claim 14, characterized in that: In step S4, the current enters the ammeter (6.4) from one side of the rotary connector (6.2) and then exits from the ammeter (6.4) to enter the other side of the rotary connector (6.2). The specific process is as follows: the current passes through the connection port (11.1), the first connecting salient pole (6.2.5) and the axial conductive adapter rod (6.2.2) of the measuring wire (11) on one side in sequence, and then enters the current test line (6.3) on one side from the bottom conductive adapter rail (6.2.1). After passing through the ammeter (6.4), it exits from the current test line (6.3) on the other side, and then passes through the conductive adapter rail (6.2.1), the axial conductive adapter rod (6.2.2) and the first connecting salient pole (6.2.5) on the other side in sequence, and exits from the connection port (11.1) of the measuring wire (11) on the other side.

17. The measurement method for the measurement structure of short-circuit current and electromagnetic field distribution under inter-turn short-circuit conditions of a single-phase transformer high-voltage winding according to claim 14, characterized in that: It also includes the following steps: S6. By adjusting the adjustable resistor box (17) and adjustable capacitor box (18) set on the circuit where the measuring wire (11) is located, the simulation measurement of the stepless short circuit condition from insulation to complete short circuit in the circuit where the two short circuit cuts (2) of the high voltage winding (1) are located is realized, as well as the simulation measurement under the condition of presence of capacitance.

18. The measurement method for the measurement structure of short-circuit current and electromagnetic field distribution of a single-phase transformer high-voltage winding under inter-turn short-circuit conditions as described in claim 14, characterized in that: It also includes the following steps: S7. By adjusting the height of the two rigid conductive strips (4) or re-inserting the rigid conductive strips (4) into the insulating sleeves (12) at the other two positions, the short-circuit current of the high-voltage winding (1) under the condition of complete short circuit can be measured. The electromagnetic field distribution under the short-circuit condition can also be measured by the electromagnetic field induction probe (13), and the measurement data can be recorded.

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