Multi-station parallel test automation device for high-voltage mutual inductor

Abstract

The invention discloses a multi-station parallel test automation device for a high-voltage mutual inductor, and relates to the technical field of mutual inductor testing, the multi-station parallel test automation device comprises a test base, a high-voltage test board and an annular station, the upper end of the test base is provided with a test frame, the upper end of the test frame is provided with a first electric push rod, and the rear end of the test frame is provided with a tester; a moving plate is arranged at the upper end of the high-voltage testing table and arranged at the lower side output end of the first electric push rod, a testing groove is formed in the lower end of the high-voltage testing table, a plurality of high-voltage conductive contact fingers distributed in an annular array are arranged in the testing groove in a sliding mode, and a plurality of electromagnetic adjusting assemblies corresponding to the high-voltage conductive contact fingers are arranged on the side wall of the testing groove. The electromagnetic adjusting assembly is used for driving the high-voltage conductive contact finger to slide, and a plurality of uniformly distributed guide rods are arranged between the moving plate and the test base; the annular station is rotationally arranged on the upper side of the test base, the annular station is located on the lower side of the high-pressure test board, and at least two sets of clamp assemblies are arranged on the annular station.

Description

Technical Field

[0001] The present invention relates to the technical field of transformer testing, in particular to a multi-station parallel testing automation device for high-voltage transformers. Background Art

[0002] High-voltage transformers are key equipment for voltage and current conversion in power systems. Testing of their insulation performance, transformation ratio accuracy and other parameters is an important step in ensuring the safe operation of power systems. Traditional high-voltage transformer test devices mostly use a single-station manual operation mode, requiring manual clamping, electrical connection and parameter collection of the transformer. This is not only time-consuming and labor-intensive, but also greatly affected by human factors. With the increasing demand for large-scale production of power equipment, the time loss caused by station switching and manual intervention in single-station testing has become increasingly prominent when facing batch testing, making it difficult to meet the requirements of modern industrial production for testing efficiency. In addition, traditional devices lack an automated station flow mechanism and cannot achieve parallel testing of multiple groups of transformers, resulting in limited overall testing capacity and becoming a key factor restricting the efficiency of the transformer production process.

[0003] In terms of electrical connections, traditional test devices generally use rigid connection methods such as bolt crimping to directly fix the high-voltage wires to the primary terminals of the transformer. This connection method suffers from high contact resistance and poor contact stability: on the one hand, the point contact form of bolt crimping can easily lead to local electric field distortion, causing partial discharge, and affecting the accuracy of test data; on the other hand, after long-term use, loosening or oxidation of the bolts will further increase the contact resistance, resulting in increased test current transmission loss and even possible test interruption due to poor contact. At the same time, traditional devices have insufficient ability to suppress electromagnetic interference. The high-frequency electromagnetic field generated during high-voltage testing can easily couple to the secondary signal circuit, causing increased errors in parameters such as ratio difference measurement, and failing to meet high-precision testing requirements. In addition, defects in the insulation structure design can also cause the electrical isolation between the high-voltage circuit and the device body to fail, posing a safety hazard.

[0004] When dealing with different types of transformers, existing high-voltage transformer test devices often require manual adjustment of the fixture position or replacement of connecting components to adapt to differences in terminal position and size. This reliance on manual adaptation not only increases the complexity of the operation, but may also lead to a decrease in connection reliability due to inadequate adjustment. At the same time, traditional devices lack a dynamic adjustment mechanism for the contact state and are unable to automatically compensate for the contact gap caused by terminal processing errors or wear, further affecting the stability of the test. At the automation control level, most devices only implement electric drive for a single action and lack an integrated system for collaborative control of multiple components. It is difficult to integrate processes such as station switching, mechanical clamping, and electrical connection into an automated cycle, resulting in a low level of continuity and intelligence in the testing process. Therefore, there is an urgent need for an automation device that can take into account efficient parallel testing, high-precision electrical connection, and adaptive compatibility to solve the efficiency, accuracy, and compatibility problems existing in the existing technology. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems raised in the above-mentioned background technology, and then proposes a multi-station parallel test automation device for high-voltage transformers. The present invention can realize the synchronous test layout of at least two groups of fixture components through the cooperation of the annular station and the stepper motor, and the up and down movement of the high-voltage test bench driven by the electric push rod can complete a single group of tests and station switching in a short time, forming an automated cycle process. This design breaks through the efficiency bottleneck of traditional single-station testing, combines multi-station parallel testing with mechanical automation control, greatly shortens the overall test cycle, and is particularly suitable for high-voltage transformer performance testing in mass production scenarios, effectively improving test efficiency and production capacity.

[0006] The technical solution adopted by the present invention to solve the technical problem is: A multi-station parallel testing automation device for a high-voltage transformer includes a test base, a high-voltage test bench and an annular station, wherein a test frame is fixedly installed on the upper end of the test base, an electric push rod is fixedly installed on the upper end of the test bench, a tester is fixedly installed on the rear end of the test frame, a movable plate is fixedly installed on the upper end of the high-voltage test bench, and the movable plate is fixedly installed on the lower output end of the electric push rod; a test slot is provided at the lower end of the high-voltage test bench, a plurality of high-voltage conductive contacts distributed in an annular array are slidably installed in the test slot, a plurality of electromagnetic adjustment components corresponding to the high-voltage conductive contacts are fixedly installed on the side walls of the test slot, and the electromagnetic adjustment components are used to drive the high-voltage conductive contacts to slide, a plurality of evenly distributed guide rods are fixedly installed between the movable plate and the test base, the annular station is rotatably installed on the upper side of the test base, and the annular station is located on the lower side of the high-voltage test bench, and at least two groups of fixture assemblies are fixedly installed on the annular station.

[0007] Preferably, the high-voltage test bench includes a base, and the test slot of the base is provided with an inner high-voltage ring, a middle shielding ring and an outer grounding ring from bottom to top. The high-voltage conductive contact finger is slidably installed on the lower surface of the inner high-voltage ring and maintains electrical connection. The inner high-voltage ring is connected to the high-voltage input interface of the test unit, and then electrically connected to the primary side terminal of the high-voltage transformer through the high-voltage conductive contact finger. The surface of the middle shielding ring is sprayed with a semiconductor coating to suppress electromagnetic interference. The outer grounding ring is connected to the grounding terminal of the base to form an equipotential shielding.

[0008] Preferably, a ceramic isolation tape is fixedly connected between the inner high-voltage ring and the middle shielding ring, and at least one insulating support is fixedly connected between the middle shielding ring and the outer grounding ring.

[0009] Preferably, the high-voltage conductive contact includes an insulating sleeve, a conductive connection block is embedded in the inner side of the insulating sleeve, a contact body is fixedly installed at the lower end of the conductive connection block, an elastic conductive sheet is fixedly connected to the upper end of the conductive connection block, and the elastic conductive sheet is in contact with the inner high-voltage ring to maintain electrical connection, and the insulating sleeve serves the purpose of insulation protection. The contact body can be in close contact with the primary side terminal to achieve good electrical connection, and the elastic conductive sheet can ensure that it always maintains surface contact with the inner high-voltage ring during the sliding process, thereby reducing contact resistance. Overall, the high-voltage conductive contact replaces the traditional bolt crimping to form a low-impedance path, ensuring stable transmission of the test current. The high-voltage conductive contact with a ring layout can form an equipotential surface, eliminating the electric field distortion caused by the discrete contact points, while traditional point contact is prone to cause local discharge. At the same time, another major advantage of the redundant design is that several high-voltage conductive contact fingers maintain good electrical connection to meet the test current requirements.

[0010] Preferably, the lower end of the insulating sleeve is also fixedly connected to an adaptive fitting, and the elastic conductive sheet is located on the outside of the contact body. The inner side of the contact body is a semi-cylindrical arc surface. The adaptive fitting is used to expand autonomously during the test to apply pressure to the contact body so that it can contact and conduct electricity more closely with the primary side terminal, thereby achieving adaptive fitting and avoiding false connection.

[0011] Preferably, the adaptive fitting includes an insulating arc plate fixedly connected to the insulating sleeve, at least one shape memory alloy spring is fixedly connected to the inner wall of the insulating arc plate, the outer end of the shape memory alloy spring is wrapped with a glass fiber insulating sleeve, and the glass fiber insulating sleeve is in contact with the contact body. The insulating arc plate serves the purpose of isolation and protection. The shape memory alloy spring utilizes the heat generated during the conduction process of the contact body, and has a tendency to expand outward after reaching the phase change temperature, and then acts on the contact body to make it fully conductively contact with the primary side terminal. The glass fiber insulating sleeve is used to isolate the shape memory alloy spring to play an insulating and protective role, and after abutting against the contact body, it fills the electrical contact gap to form full metal-metal contact.

[0012] Preferably, the electromagnetic adjustment component includes a shielding box, which is provided with a telescopic slot near one end of the insulating sleeve, a miniature electromagnet is fixedly installed inside the telescopic slot, a slide is slidably installed at the opening of the telescopic slot, the inner end of the slide is fixedly connected to a permanent magnet, the outer end of the slide is fixedly connected to a synchronization plate, and the synchronization plate and the insulating sleeve are fixedly connected, and the left and right side walls of the slide are fixedly connected with limiting sliders, and the left and right side walls of the telescopic slot are provided with limiting sliders matching the limiting sliders, and magnetic fields in different directions are applied to the permanent magnet through the shielding box, thereby driving the slide to move in different directions, and the insulating sleeve is driven to move its position through the synchronization plate, thereby realizing precise positioning and electrical connection of the primary side high-voltage terminal, ensuring low impedance and high reliability of the high-voltage connection, which not only meets the geometric compatibility of terminals of different types of transformers, but also improves test accuracy.

[0013] Preferably, the annular workstation includes an annular test disk rotatably mounted on the upper end of the test base, a stepper motor is fixedly mounted on the lower end of the test base, the output end of the stepper motor is fixedly connected to the center of the annular test disk, and an annular groove is provided at the upper end of the annular test disk. The stepper motor is used to drive the annular test disk to rotate, thereby realizing position adjustment between different workstations.

[0014] Preferably, the fixture assembly includes a mounting frame, which is fixedly mounted on the upper surface of the annular groove through a grounding seat, an electric push rod 2 is fixedly mounted on the inner side of the mounting frame, a junction box is provided on the outer side of the mounting frame, and the output end of the electric push rod 2 is fixedly connected to the junction box, a plurality of evenly distributed clamping rods are fixedly connected to the outer end of the junction box, a plurality of junction slots are also provided at the outer end of the junction box, and secondary side connection terminals are clamped at the junction slots, the electric push rod 2 drives the junction box to move, and the high-voltage transformer is mechanically fixed by the clamping rod to maintain stability during the test, and it is also convenient for the high-voltage conductive contact to be connected to the primary side high-voltage terminal, and at the same time, the secondary side connection terminal can be connected to the secondary side terminal of the transformer.

[0015] Preferably, the secondary side connection terminal includes a conductive terminal, the outer end of the conductive terminal is fixedly connected to a semiconductor shielding sleeve, the inner end of the semiconductor shielding sleeve is fixedly connected to a protective sleeve, and the protective sleeve is clamped at the opening of the wiring slot, the inner end of the conductive terminal is fixedly connected to an insulated wire, and the insulated wire extends into the wiring slot. When facing different transformer models and position differences of the secondary side terminals, the secondary side connection terminal can be manually pulled out, and the connection position can be adjusted arbitrarily by utilizing the characteristics of the insulated wire, and it is physically isolated from the high-voltage circuit. The semiconductor shielding sleeve is used to suppress the coupling interference of the high-voltage electric field on the low-voltage signal, and the protective sleeve plays a role in protecting the conductive terminal and the insulated wire, and can be stably clamped at the opening of the wiring slot.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This solution utilizes circular workstations and stepper motors to achieve synchronized testing of at least two fixtures. Combined with the vertical movement of the high-voltage test bench driven by an electric push rod, single-group testing and workstation switching can be completed in a short period of time, creating an automated, cyclical process. This design overcomes the efficiency bottleneck of traditional single-station testing by combining multi-station parallel testing with mechanical automation control, significantly shortening the overall test cycle. It is particularly suitable for high-voltage transformer performance testing in mass production scenarios, effectively improving testing efficiency and production capacity.

[0017] 2. In this solution, the high-voltage test bench utilizes a three-layer composite structure consisting of an inner high-voltage ring, a middle shielding ring, and an outer grounding ring. This structure, combined with the electrical isolation provided by the ceramic isolation tape and insulating struts, forms an equipotential shielding system. Furthermore, the high-voltage conductive contacts maintain surface contact with the inner high-voltage ring via elastic conductive sheets, replacing the traditional low-impedance bolt-on design to ensure stable test current transmission. The semiconductor coating of the middle shielding ring and the shielding sleeve of the secondary-side connection terminals synergistically suppress electromagnetic interference, improving the signal-to-noise ratio of signal transmission during testing and ensuring the accuracy of key parameters such as ratio difference measurements.

[0018] 3. In this solution, the adaptive contact elements of the high-voltage conductive fingers utilize the thermally induced deformation properties of shape memory alloy springs. When heated, they automatically expand, pushing the fingers against the terminals and compensating for contact gaps. The electromagnetic adjustment assembly drives radial movement of the fingers through magnetic field coupling, enabling precise positioning of terminals for different transformer models. This design not only addresses the problem of partial discharge easily induced by traditional point contacts, but also adapts to the varying terminal positions of different transformer models through flexible connections and a modular clamping structure. This ensures reliable electrical connections and geometric compatibility without manual adjustments, reducing operational complexity and testing errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The overall structure of the present invention is shown in FIG. Figure 1 ; Figure 2 The overall structure of the present invention is shown in FIG. Figure 2 ; Figure 3 Schematic diagram of the structure of the clamp assembly of the present invention Figure 1 ; Figure 4 Schematic diagram of the structure of the clamp assembly of the present invention Figure 2 ; Figure 5 This is a schematic structural diagram of the high-voltage test bench portion of the present invention; Figure 6 This is a disassembled structural diagram of the high-voltage test bench of the present invention; Figure 7 This is a schematic structural diagram of a high-voltage conductive contact finger of the present invention; Figure 8 This is a disassembled structural diagram of the high-voltage conductive contact finger of the present invention; Figure 9 For the present invention Figure 8 Schematic diagram of the structure at A in the middle; Figure 10 It is a structural schematic diagram of the electromagnetic adjustment component of the present invention.

[0020] Among them: 1. Test base; 2. Test frame; 3. Electric push rod 1; 4. Moving plate; 5. Guide rod; 6. Annular station; 601. Annular test plate; 602. Annular groove; 603. Stepper motor; 7. Fixture assembly; 701. Mounting frame; 702. Electric push rod 2; 703. Junction box; 704. Clamping rod; 705. Secondary side connection terminal; 7051. Connection terminal; 7052. Semiconductor shielding sleeve; 7053. Protective sleeve; 7054. Insulated wire; 706. Grounding seat; 8. High voltage test bench; 801. Base; 802. Inner high voltage ring; 8 03. Middle shielding ring; 804. Outer grounding ring; 805. Ceramic isolation tape; 806. Insulating pillar; 9. High-voltage conductive contact finger; 901. Insulating sleeve; 902. Contact finger body; 903. Conductive connecting block; 904. Elastic conductive sheet; 905. Adaptive fitting; 9051. Insulating arc plate; 9052. Shape memory alloy spring; 9053. Glass fiber insulating sleeve; 10. Electromagnetic adjustment assembly; 1001. Shielding box; 1002. Micro electromagnet; 1003. Slide seat; 1004. Permanent magnet; 1005. Limit slider; 1006. Synchronous plate. DETAILED DESCRIPTION

[0021] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0022] Example 1: Figure 1 and Figure 2 As shown, this embodiment provides a multi-station parallel testing automation device for a high-voltage transformer, including a test base 1, a high-voltage test bench 8 and an annular station 6. A test frame 2 is fixedly installed on the upper end of the test base 1, an electric push rod 3 is fixedly installed on the upper end of the test bench 2, a tester is fixedly installed on the rear end of the test frame 2, a movable plate 4 is fixedly installed on the upper end of the high-voltage test bench 8, and the movable plate 4 is fixedly installed on the lower output end of the electric push rod 3. A test slot is provided at the lower end of the high-voltage test bench 8, and a plurality of high-voltage conductive contact fingers 9 distributed in a circular array are slidably installed in the test slot. A plurality of evenly distributed guide rods 5 are fixedly installed between the movable plate 4 and the test base 1. The annular station 6 is rotatably installed on the upper side of the test base 1, and the annular station 6 is located on the lower side of the high-voltage test bench 8. At least two groups of fixture assemblies 7 are fixedly installed on the annular station 6.

[0023] like Figure 5 and Figure 6 As shown, the high-voltage test bench 8 includes a base 801, and the test slot of the base 801 is provided with an inner high-voltage ring 802, a middle shielding ring 803 and an outer grounding ring 804 from bottom to top. The high-voltage conductive contact finger 9 is slidably installed on the lower surface of the inner high-voltage ring 802 and maintains electrical connection. The inner high-voltage ring 802 is connected to the high-voltage input interface of the test unit, and then conductively connected to the primary side terminal of the high-voltage transformer through the high-voltage conductive contact finger 9. The surface of the middle shielding ring 803 is sprayed with a semiconductor coating to suppress electromagnetic interference. The outer grounding ring 804 is connected to the grounding terminal of the base 801 to form an equipotential shield.

[0024] A ceramic isolation tape 805 is fixedly connected between the inner high-voltage ring 802 and the middle shielding ring 803 , and at least one insulating support 806 is fixedly connected between the middle shielding ring 803 and the outer grounding ring 804 .

[0025] It should be noted that the high-voltage test bench 8, as the core electrical connection unit of the device, adopts a composite design consisting of a three-layer annular conductive structure and a ceramic insulating base. Base 801 is constructed from high-purity alumina ceramic, effectively isolating the high-voltage circuit from the device body. The inner high-voltage ring 802, embedded within the base, is a T2 copper forging precision-turned to a surface roughness Ra ≤ 0.4μm and a conductivity of 98% IACS, ensuring test current transmission losses of ≤ 0.1%. The middle shielding ring 803 utilizes a 304 stainless steel substrate, coated with a 20μm thick semiconductor tin oxide coating via a magnetron sputtering process to form an electromagnetic shielding layer that attenuates over 90% of high-frequency electromagnetic interference. The outer grounding ring 804 is constructed from industrial-pure aluminum and rigidly connects to the base's grounding terminal, forming an equipotential shielding system with a grounding resistance of ≤ 0.1mΩ.

[0026] A 5mm-wide ceramic isolation strip 805 is placed between the inner high-voltage ring 802 and the middle shielding ring 803. Made of 99% alumina ceramic via tape casting, it boasts a breakdown voltage ≥50kV and creepage distances meeting 35kV voltage rating requirements. Six quartz glass insulating struts 806, each 10mm in diameter and 20mm long, with a compressive strength ≥30kV, support the middle and outer layers, ensuring electrical clearance and mechanical stability.

[0027] like Figure 7-Figure 9 As shown, the high-voltage conductive contact finger 9 includes an insulating sleeve 901, and a conductive connection block 903 is embedded and connected inside the insulating sleeve 901. The lower end of the conductive connection block 903 is fixedly mounted with a contact finger body 902, and the upper end of the conductive connection block 903 is fixedly connected with an elastic conductive sheet 904. The elastic conductive sheet 904 is in contact with the inner high-voltage ring 802 to maintain electrical connection. The insulating sleeve 901 serves the purpose of insulation protection. The contact finger body 902 can be in close contact with the primary-side terminal to achieve a good electrical connection. The elastic conductive sheet 904 can ensure that it always maintains surface contact with the inner high-voltage ring 802 during the sliding process, thereby reducing contact resistance. Overall, the high-voltage conductive contact finger 9 replaces the traditional bolt crimping to form a low-impedance path, ensuring stable transmission of the test current. The ring-shaped high-voltage conductive contact finger 9 can form an equipotential surface, eliminating the electric field distortion caused by the discrete contact points, while traditional point contact is prone to cause partial discharge. At the same time, another major advantage of the redundant design is that several high-voltage conductive contact fingers 9 can meet the test current requirement by maintaining good electrical connection.

[0028] It should be noted that the high-voltage conductive contact finger 9 utilizes a composite elastic structure. The insulating sleeve 901 is injection-molded from polyetheretherketone (PEEK), heat-resistant to 260°C and insulated. The conductive connection block 903 is precision-molded inside. The conductive connection block 903 is made of beryllium bronze (QBe2) and plated with a 5μm-thick layer of pure silver, resulting in a contact resistance of ≤30μΩ. The contact finger body 902 is laser-welded to the conductive connection block 903. The contact finger head is designed as a semi-cylindrical arc with a surface roughness of Ra ≤0.1μm, ensuring arc-shaped contact with the outer edge of the transformer's primary terminal.

[0029] The elastic conductive sheet 904 is a 0.3mm thick phosphor bronze strip, which is stamped into a wavy elastic structure. The lower end is fixed to the conductive connection block 903 by a countersunk screw, and the upper end maintains surface contact with the lower surface of the inner high-voltage ring 802 with a contact pressure of 0.5-1N, ensuring uninterrupted electrical connection when the contact finger slides.

[0030] like Figure 1As shown, the annular workstation 6 includes an annular test disk 601 rotatably mounted on the upper end of the test base 1, a stepper motor 603 is fixedly mounted on the lower end of the test base 1, the output end of the stepper motor 603 is fixedly connected to the center of the annular test disk 601, and an annular groove 602 is provided at the upper end of the annular test disk 601. The stepper motor 603 is used to drive the annular test disk 601 to rotate, thereby realizing position adjustment between different workstations.

[0031] like Figure 3 and Figure 4 As shown, the fixture assembly 7 includes a mounting frame 701, which is fixedly mounted on the upper surface of the annular groove 602 through a grounding seat 706, and an electric push rod 2 702 is fixedly mounted on the inner side of the mounting frame 701, and a junction box 703 is provided on the outer side of the mounting frame 701, and the output end of the electric push rod 2 702 is fixedly connected to the junction box 703, and a plurality of evenly distributed clamping rods 704 are fixedly connected to the outer end of the junction box 703. A plurality of wiring grooves are also provided at the outer end of the junction box 703, and secondary side connection terminals 705 are clamped at the wiring grooves. The electric push rod 2 702 drives the junction box 703 to move, and the high-voltage transformer is mechanically fixed by the clamping rod 704 to maintain stability during the test, and also facilitate the connection of the high-voltage conductive contact finger 9 with the primary side high-voltage terminal. At the same time, the secondary side connection terminal 705 can be connected to the secondary side terminal of the transformer.

[0032] The secondary side connection terminal 705 includes a conductive terminal 7051, the outer end of the conductive terminal 7051 is fixedly connected to a semiconductor shielding sleeve 7052, the inner end of the semiconductor shielding sleeve 7052 is fixedly connected to a protective sleeve 7053, and the protective sleeve 7053 is clamped at the opening of the wiring slot, the inner end of the conductive terminal 7051 is fixedly connected to an insulated wire 7054, and the insulated wire 7054 extends into the wiring slot. When facing different transformer models and differences in the position of the secondary side terminals, the secondary side connection terminal 705 can be manually pulled out, and the connection position can be adjusted arbitrarily by utilizing the characteristics of the insulated wire 7054, and it is physically isolated from the high-voltage circuit. The semiconductor shielding sleeve 7052 is used to suppress the coupling interference of the high-voltage electric field on the low-voltage signal. The protective sleeve 7053 protects the conductive terminal 7051 and the insulated wire 7054, and can be stably clamped at the opening of the wiring slot.

[0033] It should be noted that the clamp assembly 7 utilizes a modular design integrating clamping and electrical connections. The mounting bracket 701 ensures the linear motion accuracy of the electric actuator 702. This actuator 702 utilizes a T8 trapezoidal lead screw coupled with a 42mm stepper motor. It features a 2mm lead, 500N thrust, ±0.5mm positioning accuracy, and a 100mm travel range, adapting to various transformer flange heights. The clamping rod 704 is made of nylon 66 and features a non-slip serration pattern with a 1mm pitch and 0.5mm depth. The friction coefficient against the transformer housing is ≥0.6, ensuring a clamping force ≥100N.

[0034] Grounding base 706 is a brass H62 forging, rigidly connected to mounting bracket 701 via M6 bolts. Junction box 703 is made of aluminum alloy and contains two independent terminal blocks, which can simultaneously connect two secondary terminals. The terminal blocks are pluggable and have a contact resistance of ≤50μΩ.

[0035] The conductive terminal 7051 of the secondary connection terminal 705 is machined from a T2 copper rod with a diameter of 4mm and a 3μm thick tin coating, providing strong oxidation resistance. The semiconductor shielding sleeve 7052 is injection-molded from conductive plastic and wraps around the exposed portion of the conductive terminal 7051, providing electromagnetic shielding. The protective sleeve 7053 is made of ABS engineering plastic and features an annular groove on its inner wall, which provides an interference fit with the wiring slot in the junction box 703, ensuring mechanical stability of the connection terminal. The insulated conductor 7054 features a multi-strand stranded copper core with a double shield of aluminum foil and braided mesh. The conductor length can be extended up to 150mm depending on the terminal position.

[0036] The adaptive clamping of the clamp assembly 7 is achieved by the displacement control of the second electric push rod 702: when the transformer is placed on the annular work station 6, the second electric push rod 702 drives the junction box 703 to move, so that the clamping rod 704 is evenly pressed against the transformer housing.

[0037] The flexible design of the secondary-side connection terminal 705 solves the problem of adapting to different terminal positions on different transformer models. If the transformer's secondary-side terminals deviate from the standard position, the insulated wire 7054 can be manually stretched to align the conductive terminal 7051 with the target terminal. The semi-conductive shielding sleeve 7052 remains wrapped around the conductive portion as the wire moves, maintaining shielding effectiveness. The slot design of the protective clamping sleeve 7053 allows the terminal to swing within a ±15° range to accommodate angular deviations. The locking friction force of ≥5N prevents the terminal from loosening during testing.

[0038] This embodiment achieves parallel connection of two secondary terminals through the coordinated optimization of mechanical clamping and electrical connection, significantly reducing the connection time for a single set of terminals. Under a 10kV high-voltage test environment, the signal-to-noise ratio of the secondary signal is improved, significantly enhancing the accuracy of the differential measurement. The low-impedance grounding design of grounding socket 706 effectively suppresses electrostatic interference, minimizing repeatability errors in test data.

[0039] It should be noted that the testers in the prior art usually have the function of collecting and analyzing voltage and current signals, but most of them use independent control panels and external connection cables. In this embodiment, the tester is improved and integrated with a central controller, which becomes the control core of the device. The tester is connected to the inner high-voltage ring 802 and the electromagnetic adjustment component 10 of the high-voltage test bench 8 through a dedicated communication cable, and can control the application of the test voltage and the adjustment of the contact finger position in real time. The central controller in the tester automatically controls the electric push rod 2 702 of the clamp assembly 7 to push the junction box 703 to move, so that the clamping rod 704 is evenly pressed against the transformer housing to achieve mechanical fixation. At the same time, the central controller controls the extension and retraction of the insulated wire 7054 of the secondary side connection terminal 705 according to the layout information of the secondary side terminal of the transformer, so that the conductive terminal 7051 is accurately docked with the target terminal. Once the transformer is installed, the tester's central controller sends instructions to the electromagnetic adjustment assembly 10 according to a preset program, driving the high-voltage conductive contact fingers 9 to adaptively adjust and ensure a reliable connection with the terminal. It then controls the inner high-voltage ring 802 to apply the test voltage and simultaneously collects and analyzes the secondary-side signal. During the test, the central controller monitors the status of each connection point in real time. If poor contact or abnormal electromagnetic interference is detected, it immediately adjusts the relevant component parameters to ensure a stable and reliable test process. After the test is completed, the central controller resets each component to prepare for the next test.

[0040] Example 2: Figure 7 and Figure 8 As shown, on the basis of Example 1, the lower end of the insulating sleeve 901 is also fixedly connected to an adaptive fitting 905, and the elastic conductive sheet 904 is located on the outside of the contact body 902, and the inner side surface of the contact body 902 is a semi-cylindrical arc surface. The adaptive fitting 905 is used to expand autonomously during the test to apply pressure to the contact body 902, so that it can be in closer contact with the primary side terminal for conductivity, thereby achieving adaptive fitting and avoiding false connection.

[0041] The adaptive fitting part 905 includes an insulating arc plate 9051 fixedly connected to the insulating sleeve 901, and at least one shape memory alloy spring 9052 is fixedly connected to the inner wall of the insulating arc plate 9051. The outer end of the shape memory alloy spring 9052 is wrapped with a glass fiber insulating sleeve 9053, and the glass fiber insulating sleeve 9053 is in contact with the contact body 902. The insulating arc plate 9051 serves the purpose of isolation and protection. The shape memory alloy spring 9052 utilizes the heat generated during the conduction process of the contact body 902. After reaching the phase change temperature, it has a tendency to expand outward, and then acts on the contact body 902 to make it fully conductively contact with the primary side terminal. The glass fiber insulating sleeve 9053 is used to isolate the shape memory alloy spring 9052 to play an insulating and protective role. After abutting against the contact body 902, it fills the electrical contact gap to form full metal-metal contact.

[0042] It should be noted that the insulating arc plate 9051 of the adaptive fitting 905 is an epoxy resin plate, and three groups of shape memory alloy springs 9052 are evenly distributed along the inner arc surface. The springs are wound with NiTi50 alloy wire, with a diameter of 0.3mm, a phase transition temperature of 65°C, and a recovery stress ≥400MPa. The outer layer is wrapped with a glass fiber insulating sleeve 9053 that is resistant to a temperature of 200°C. When it abuts against the outer side of the contact body 902, it can generate a radial thrust of 0.2-0.5N.

[0043] The annular array layout of the high-voltage conductive contact fingers 9 forms an equipotential contact surface, reducing the electric field distortion rate from 20% to below 5% compared to traditional point contact designs. The elastic conductive sheet 904 ensures a large contact area with the inner high-voltage ring 802 within a ±5mm radial movement range, reducing contact resistance fluctuations. The adaptive fitting 905 utilizes the thermally induced deformation properties of the shape memory alloy spring 9052. When the high-voltage conductive contact finger 9 is heated to above 65°C by the test current, the shape memory alloy spring 9052 expands, pushing the contact finger body 902 against the terminal, automatically compensating for the slight contact gap, increasing contact pressure, and further reducing contact resistance.

[0044] Example 3: Figure 5 and Figure 10 As shown, based on Example 2, a plurality of electromagnetic adjustment components 10 corresponding to the high-voltage conductive contact fingers 9 are fixedly installed on the side wall of the test slot, and the electromagnetic adjustment components 10 are used to drive the high-voltage conductive contact fingers 9 to slide.

[0045] The electromagnetic adjustment assembly 10 includes a shielding box 1001, which has a telescopic slot at one end near the insulating sleeve 901. A micro electromagnet 1002 is fixedly installed inside the telescopic slot. A slide 1003 is slidably installed at the opening of the telescopic slot. The inner end of the slide 1003 is fixedly connected to a permanent magnet 1004. The outer end of the slide 1003 is fixedly connected to a synchronization plate 1006, and the synchronization plate 1006 is fixedly connected to the insulating sleeve 901. The left and right side walls of the slide 1003 are fixedly connected to limit sliders 1005. , limit slides matching the limit slide 1005 are provided on the left and right side walls of the telescopic slot. Magnetic fields in different directions are applied to the permanent magnet 1004 through the shielding box 1001, thereby driving the slide 1003 to move in different directions, and the insulating sleeve 901 is driven to move its position through the synchronization plate 1006, thereby realizing precise positioning and electrical connection of the primary side high-voltage terminal, ensuring low impedance and high reliability of the high-voltage connection, meeting the geometric compatibility of different types of transformer terminals, and improving the test accuracy.

[0046] It should be noted that the electromagnetic adjustment assembly 10 utilizes a modular magnetic drive design. The shielding box 1001 is a sealed chamber made of an iron-nickel alloy with a wall thickness of 2mm and a magnetic permeability of ≥8000, which can suppress over 95% of magnetic field leakage. The miniature electromagnet 1002 installed within the box utilizes an E-shaped silicon steel core with 2000 turns and a wire diameter of 0.15mm. When supplied with a DC current of 0.5-2A, it can generate a magnetic field strength of 0.1-0.4T. The permanent magnet 1004 is made of neodymium iron boron N52, measures 5mm × 5mm × 10mm, and has a remanence of 1.4T. It is securely attached to the slide 1003 using epoxy resin adhesive.

[0047] Slide 1003 is made of aluminum alloy 6061-T6 and is CNC-milled into a T-shaped structure. The two limiting sliders 1005 on each side are made of polyoxymethylene (POM) plastic and slide in conjunction with the limiting grooves on the inner wall of the telescopic slot of shielding box 1001, ensuring high-precision movement of slide 1003. Synchronizing plate 1006 is a 0.8mm thick aluminum alloy plate. One end is threaded into slide 1003, and the other end is fixed to insulating sleeve 901 via countersunk screws, forming a rigid transmission chain.

[0048] The electromagnetic adjustment assembly 10 operates based on magnetic field coupling: When a positive current flows through the microelectromagnet 1002, it generates a magnetic field with the same polarity as the permanent magnet 1004, pushing the slide 1003 outward with repulsive force. When a reverse current flows through it, the attractive force of the opposite polarity magnetic field pulls the slide 1003 inward. A central controller adjusts the current using a PWM signal, precisely controlling the displacement of the slide 1003 and significantly improving its response speed compared to traditional hydraulic drives.

[0049] The precise coordination between the limiting slider 1005 and the limiting slide groove effectively suppresses the lateral shaking of the slide 1003 during movement, ensures the accuracy of radial movement of the high-voltage conductive contact finger 9, greatly reduces the coaxiality error between the high-voltage conductive contact finger 9 and the primary-side high-voltage terminal, and lays the foundation for low-impedance electrical connection.

[0050] When the ring-shaped workstation 6 receives a station switching command, the central controller controls the rotation of the stepper motor 603, moving the target workstation directly below the high-voltage test bench 8. Once positioned, the central controller sends a current adjustment command to the microelectromagnet 1002 of the electromagnetic adjustment assembly 10 based on the transformer model parameters. This drives the slide 1003, which in turn radially displaces the high-voltage conductive contact finger 9, completing the adaptive adjustment of the contact finger's inner diameter. This entire process requires no human intervention, and the unified control of the tester ensures precise coordination of mechanical movements, significantly improving testing efficiency.

[0051] The operating principle of the device disclosed in the present invention is as follows: After the stepper motor 603 of the annular station 6 rotates the transformer to be tested directly below the high-voltage test bench 8, the electric push rod 13 drives the movable plate 4 downward, gradually approaching the test slot of the high-voltage test bench 8 to the primary terminal of the transformer. At this time, the micro-electromagnet 1002 of the electromagnetic adjustment assembly 10, based on the transformer model parameters preset by the tester's central controller, generates a magnetic field force that drives the permanent magnet 1004 to move the slide 1003 radially. The inner diameter of the high-voltage conductive contact finger 9 is adaptively adjusted to the target value through the synchronization plate 1006.

[0052] When the high-voltage conductive finger 9 contacts the terminal surface, the conductive process of the finger body 902 generates Joule heat, raising the temperature of the shape memory alloy spring 9052 to above 65°C. This causes the shape memory alloy spring 9052 to transform from the martensite phase to the austenite phase, generating a radial expansion force that pushes the finger body 902 against the outer edge of the terminal, filling any gaps. Simultaneously, the elastic conductive sheet 904 maintains surface contact with the inner high-voltage ring 802 throughout the finger's movement, ensuring uninterrupted electrical connection of the high-voltage circuit.

[0053] After receiving the positioning completion signal, the electric push rod 2 (702) of the clamp assembly 7 pushes the junction box 703, causing the clamping rod 704 to evenly press against the transformer housing, achieving mechanical fixation. The conductive terminals 7051 of the secondary connection terminals 705, supported by the flexible insulated conductors 7054, automatically align with the transformer's secondary terminals, while the semiconductor shielding sleeve 7052 simultaneously forms an electromagnetic shield. At this point, the inner high-voltage ring 802 applies a test voltage, such as a 10kV power frequency voltage, to the transformer's primary side via the high-voltage conductive contacts 9. The middle shielding ring 803 suppresses electromagnetic interference, and the outer grounding ring 804 ensures equipotential safety.

[0054] During the test, the central controller monitors the infrared temperature probe data in real time and automatically reduces the test current when the temperature of the high-voltage conductive contact finger 9 exceeds 80°C. Simultaneously, it collects secondary-side signals and transmits them via shielded wires to the tester for error analysis. After the test is complete, electric actuators 1 (3) and 2 (702) are synchronously reset, and the stepper motor 603 drives the annular test disc 601 to rotate 180°, moving the transformer at the next station to the test position. The process repeats. The entire test cycle, including station switching, is controlled within 3 minutes, achieving efficient multi-station parallel testing.

[0055] In the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "vertical", "horizontal", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are intended only to describe the present invention and do not require that the present invention must be constructed or operated in a specific direction. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" in the present invention should be understood in a broad sense. For example, they can be connected or detachably connected; they can be directly connected or indirectly connected through an intermediate component. For those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0056] The above is a preferred operating mode of the present invention. The description of the specific operating mode is only for a better understanding of the concept of the present invention. For those skilled in the art, it is clear that several improvements or equivalent substitutions can be made according to the principles of the present invention, and these improvements or equivalent substitutions are also considered to fall within the scope of protection of the present invention.

Claims

1. High-voltage transformer multi-station parallel test automation device, characterized by: The invention comprises a test base (1), a high-voltage test bench (8) and an annular workstation (6), wherein a test stand (2) is installed on the upper end of the test base (1), an electric push rod (3) is arranged on the upper end of the test stand (2), and a tester is arranged at the rear end of the test stand (2); a movable plate (4) is arranged on the upper end of the high-voltage test bench (8), and the movable plate (4) is arranged at the lower output end of the electric push rod (3); a test slot is arranged at the lower end of the high-voltage test bench (8), and a plurality of high-voltage conductive contacts distributed in an annular array are slidably arranged in the test slot. The test slot has a plurality of electromagnetic adjustment components (10) corresponding to the high-voltage conductive contact fingers (9), and the electromagnetic adjustment components (10) are arranged on the side wall of the test slot, and the electromagnetic adjustment components (10) are used to drive the high-voltage conductive contact fingers (9) to slide, and a plurality of evenly distributed guide rods (5) are arranged between the movable plate (4) and the test base (1); the annular station (6) is rotatably arranged on the upper side of the test base (1), and the annular station (6) is located on the lower side of the high-voltage test bench (8), and at least two sets of clamp components (7) are arranged on the annular station (6).

2. The high-voltage transformer multi-station parallel test automation device according to claim 1, characterized in that: The high-voltage test bench (8) comprises a base (801), wherein an inner high-voltage ring (802), a middle shielding ring (803) and an outer grounding ring (804) are sequentially arranged in a test slot of the base (801) from bottom to top, and the high-voltage conductive contact finger (9) is slidably mounted on the lower surface of the inner high-voltage ring (802) and maintains electrical connection.

3. The high-voltage transformer multi-station parallel test automation device according to claim 2, characterized in that: A ceramic isolation tape (805) is fixedly connected between the inner high-voltage ring (802) and the middle shielding ring (803), and at least one insulating support (806) is fixedly connected between the middle shielding ring (803) and the outer grounding ring (804).

4. The high-voltage transformer multi-station parallel test automation device according to claim 3, characterized in that: The high-voltage conductive contact finger (9) comprises an insulating sleeve (901), a conductive connection block (903) is embedded inside the insulating sleeve (901), a contact finger body (902) is fixedly provided at the lower end of the conductive connection block (903), and an elastic conductive sheet (904) is fixedly provided at the upper end of the conductive connection block (903), and the elastic conductive sheet (904) is in contact with the inner high-voltage ring (802) to maintain electrical connection.

5. The high-voltage transformer multi-station parallel test automation device according to claim 4, characterized in that: An adaptive fitting part (905) is also fixedly provided at the lower end of the insulating sleeve (901), and the elastic conductive sheet (904) is located outside the contact finger body (902), and the inner side surface of the contact finger body (902) is a semi-cylindrical arc surface.

6. The high-voltage transformer multi-station parallel test automation device according to claim 5, characterized in that: The adaptive fitting part (905) comprises an insulating arc plate (9051) fixedly connected to the insulating sleeve (901), at least one shape memory alloy spring (9052) is fixedly arranged on the inner side wall of the insulating arc plate (9051), the outer end of the shape memory alloy spring (9052) is wrapped with a glass fiber insulating sleeve (9053), and the glass fiber insulating sleeve (9053) is in contact with the contact finger body (902).

7. The high-voltage transformer multi-station parallel test automation device according to claim 6, characterized in that: The electromagnetic adjustment component (10) includes a shielding box (1001), a telescopic slot is provided at one end of the shielding box (1001) close to the insulating sleeve (901), a micro electromagnet (1002) is fixedly provided inside the telescopic slot, a slide seat (1003) is slidably provided at the opening of the telescopic slot, a permanent magnet (1004) is fixedly provided at the inner end of the slide seat (1003), a synchronization plate (1006) is fixedly provided at the outer end of the slide seat (1003), and the synchronization plate (1006) is fixedly connected to the insulating sleeve (901), and a limit slide block (1005) is fixedly provided on both left and right side walls of the slide seat (1003), and a limit slide block matching the limit slide block (1005) is provided on both left and right side walls of the telescopic slot.

8. The high-voltage transformer multi-station parallel test automation device according to claim 7, characterized in that: The annular workstation (6) comprises an annular test disc (601) rotatably mounted on the upper end of the test base (1); a stepper motor (603) is fixedly arranged at the lower end of the test base (1); an output end of the stepper motor (603) is fixedly connected to the center of the annular test disc (601); and an annular groove (602) is arranged at the upper end of the annular test disc (601).

9. The high-voltage transformer multi-station parallel test automation device according to claim 8, characterized in that: The clamp assembly (7) includes a mounting frame (701), the mounting frame (701) is fixedly arranged on the upper surface of the annular groove (602) through a grounding seat (706), the electric push rod 2 (702) is fixedly arranged on the inner side of the mounting frame (701), the junction box (703) is arranged on the outer side of the mounting frame (701), and the output end of the electric push rod 2 (702) is fixedly connected to the junction box (703), the outer end of the junction box (703) is fixedly connected to a plurality of evenly distributed clamping rods (704), and the outer end of the junction box (703) is also provided with a plurality of junction slots, and the junction slots are clamped with secondary side connection terminals (705).

10. The high-voltage transformer multi-station parallel test automation device according to claim 9, characterized in that: The secondary side connection terminal (705) comprises a conductive terminal (7051), the outer end of the conductive terminal (7051) is fixedly connected to a semiconductor shielding sleeve (7052), the inner end of the semiconductor shielding sleeve (7052) is fixedly connected to a protective clamping sleeve (7053), and the protective clamping sleeve (7053) is clamped at the opening of the wiring slot, and the inner end of the conductive terminal (7051) is fixedly connected to an insulated wire (7054), and the insulated wire (7054) extends into the wiring slot.

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