Integrated sleeve type electronic voltage transformer

Abstract

The utility model relates to the technical field of transformers in power equipment, in particular to an integrated sleeve type electronic voltage transformer. Comprising a conducting rod, a voltage measuring module, a capacitance monitoring module and an insulating and packaging structure, and the conducting rod is arranged at the central axis position of the insulating and packaging structure in a penetrating mode; the voltage measuring module comprises a primary ceramic capacitor and a secondary capacitor, the primary ceramic capacitor is fixedly connected to the outer wall of the conducting rod, and the secondary capacitor is connected with the primary ceramic capacitor in series; the capacitance monitoring module comprises a capacitance sensing net, the capacitance sensing net is of a cylindrical metal net structure and is coaxially arranged outside the conducting rod, and the capacitance sensing net and the conducting rod form a monitoring capacitor which is used for sensing and outputting a capacitance value reflecting the state of an epoxy resin insulating medium; and the insulating and packaging structure is an epoxy resin shell formed by integrally curing an epoxy resin insulating material. The utility model has the advantages of function integration, convenient installation, maintenance-free property, high precision and the like, and the transformation difficulty and cost are reduced.

Description

Technical Field

[0001] This utility model relates to the field of transformer technology in power equipment, specifically to an integrated bushing-type electronic voltage transformer. Background Technology

[0002] Ring main units are indispensable key power distribution equipment in modern urban power distribution networks, industrial parks, commercial centers, large buildings, infrastructure (such as airports, train stations, and hospitals), residential communities, and renewable energy power plants (such as wind farms and photovoltaic power stations) and their substations. They have advantages such as high reliability, compact structure, and high degree of modularity, and are widely used in power grids.

[0003] However, the internal space of ring main units is usually extremely limited, and they generally adopt a fully insulated and sealed structure. This characteristic makes it very difficult to directly install traditional electromagnetic voltage transformers (PTs) or large electronic transformers (such as electronic voltage transformers EVTs) inside the cabinet. With the in-depth advancement of distribution network automation transformation, the number of secondary equipment that needs to be integrated into ring main units has increased significantly, and the demand for voltage signal acquisition, measurement, monitoring, and protection functions is becoming increasingly prominent.

[0004] The main problems with existing technologies are:

[0005] Limited installation space and structural conflicts: The small, fully insulated structure of the ring main unit cannot accommodate large traditional or electronic instrument transformers.

[0006] High retrofit costs: To meet automation requirements, dedicated physical transformers (PTs) are typically needed, which not only incur high equipment costs but also occupy valuable cabinet space. Retrofitting existing ring main units is even more challenging, complex, and extremely costly. Utility Model Content

[0007] To address the problems of difficult installation and high retrofitting costs of traditional current transformers in ring main units, this invention provides an integrated bushing-type electronic voltage transformer that integrates voltage measurement and capacitor status monitoring functions, adapts to the compact space of ring main units, and reduces the difficulty and cost of retrofitting.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] This utility model provides an integrated bushing type electronic voltage transformer, including a conductive rod, a voltage measurement module, a capacitance monitoring module, and an insulation and encapsulation structure, wherein the conductive rod is disposed through the central axis of the insulation and encapsulation structure;

[0010] The voltage measurement module includes a primary ceramic capacitor and a secondary capacitor. The primary ceramic capacitor is fixedly connected to the outer wall of the conductive rod, and the secondary capacitor is connected in series with the primary ceramic capacitor.

[0011] The capacitance monitoring module includes a capacitance sensing mesh, which is a cylindrical metal mesh structure and is coaxially arranged outside the conductive rod. The capacitance sensing mesh and the conductive rod constitute a monitoring capacitor, which is used to sense and output the capacitance value that reflects the state of the epoxy resin insulating medium.

[0012] The insulation and encapsulation structure is made of epoxy resin insulating material that is cured and molded into an epoxy resin shell, which completely covers and fixes the conductive rod, voltage measurement module and capacitance sensing network.

[0013] The conductive rod is made of conductive metal, and both ends of the conductive rod have threaded holes or fixing devices, with both ends exposed by an epoxy resin shell.

[0014] The epoxy resin shell includes a cone, a flange, and a cylindrical body arranged sequentially from front to back, wherein one side of the flange has a cantilever structure.

[0015] The primary ceramic capacitor is disposed within the cylindrical body to form the high-voltage arm of the capacitor voltage divider circuit, and the secondary capacitor is disposed within the cantilever structure to form the low-voltage arm of the capacitor voltage divider circuit. The two ends of the secondary capacitor are connected to a voltage-shielded twisted pair cable, which is disposed on the end face of the cantilever structure to output a secondary voltage signal.

[0016] The voltage-shielded twisted pair cable is a two-core shielded cable with the two cores twisted together and an outer metal braided shielding layer. The shielding layer is connected to a grounding terminal, which is located on the end face of the cantilever structure.

[0017] The capacitive sensing network is connected to the capacitor terminal via leads, and the capacitor terminal is located on the end face of the cantilever structure.

[0018] The advantages and beneficial effects of this utility model are as follows: This utility model provides an integrated bushing-type electronic voltage transformer, which has multiple advantages such as functional integration, convenient installation, maintenance-free operation, and high precision. It not only integrates voltage measurement and capacitance status monitoring functions into a single bushing structure to replace the standard bushing of the ring main unit, solving the problem of large space occupation by traditional transformers, but also supports direct installation in existing ring main units without modification thanks to the standardized outer cone, flange plate, and cylindrical tail end design, reducing the difficulty and cost of modification. Its epoxy resin integral curing fully sealed structure is moisture-proof and pollution-resistant, requires no maintenance during its lifespan, and can sense the state of the insulation medium in real time through the capacitance sensing network to warn of deterioration risks. Combined with voltage shielded twisted pair cable and ceramic capacitor voltage divider technology, it can maintain high-precision measurement in complex electromagnetic environments, while saving the cost of purchasing independent PTs and cabinet expansion construction costs, thus maximizing cost-effectiveness.

[0019] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0020] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0022] Figure 1 This is a schematic diagram of the structure of an integrated bushing-type electronic voltage transformer according to this utility model;

[0023] Figure 2 for Figure 1 AA section view;

[0024] Figure 3 This is a front view of an integrated bushing-type electronic voltage transformer according to this utility model.

[0025] Figure 4 for Figure 3 The left view;

[0026] Figure 5 This is a circuit diagram of the voltage measurement module in this utility model;

[0027] Figure 6 This is the wiring circuit diagram of the voltage shielded twisted pair cable in this utility model.

[0028] The components are: 1. Epoxy resin shell; 4. Sealing groove; 5. Conductive rod; 6. Capacitive sensing mesh; 7. Primary ceramic capacitor; 8. Secondary capacitor; 9. Voltage shielded twisted pair cable; 10. Capacitor terminal; 11. Grounding terminal; 12. Shielded wire; 101. Cone; 102. Flange plate; 103. Cylindrical-like shape. Detailed Implementation

[0029] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0030] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0031] See Figures 1 to 4 As shown, this utility model provides an integrated bushing-type electronic voltage transformer, including a conductive rod 5, a voltage measurement module, a capacitance monitoring module, and an insulation and encapsulation structure. The conductive rod 5 is disposed through the central axis of the insulation and encapsulation structure. The voltage measurement module includes a primary ceramic capacitor 7 and a secondary capacitor 8. The high-voltage end of the primary ceramic capacitor 7 is fixedly connected to the outer wall of the conductive rod 5, and the secondary capacitor 8 is connected in series with the primary ceramic capacitor 7. The capacitance monitoring module includes a capacitance sensing mesh 6, which is a cylindrical metal mesh structure and is coaxially arranged outside the conductive rod 5. The capacitance sensing mesh 6 and the conductive rod 5 constitute a monitoring capacitor, used to sense and output the capacitance value reflecting the state of the epoxy resin insulating medium. The insulation and encapsulation structure is an epoxy resin shell 1 integrally cured and molded from epoxy resin insulating material, which completely covers and cures the conductive rod 5, the voltage measurement module, and the capacitance sensing mesh 6, forming a fully sealed, maintenance-free integrated structure. During the curing process, reliable insulation between electrical components and between components and the shell is ensured.

[0032] See Figure 1 As shown, in the embodiment of this utility model, the conductive rod 5 is made of conductive metal, and both ends of the conductive rod 5 are provided with threaded holes or other forms of fixing devices, and both ends of the conductive rod 5 are exposed outside the epoxy resin shell 1.

[0033] See Figure 3As shown in the embodiment of this utility model, the epoxy resin shell 1 includes a cone 101, a flange plate 102, and a near-cylinder 103 arranged sequentially from front to back, wherein one side of the flange plate 102 is a cantilever structure. The cone 101 is an outer cone conforming to standard dimensions, which can be connected to a standard equipment cone sleeve. The flange plate 102 has a sealing groove 4, which is used to install a sealing ring, and the flange plate 102 can be fixed and sealed to the equipment panel. The near-cylinder 103 is a regular approximate cylinder, which facilitates installation through openings in the switchgear.

[0034] Furthermore, a primary ceramic capacitor 7 is disposed within the cylindrical body 103 to form the high-voltage arm of the capacitor voltage divider circuit, and the primary ceramic capacitor 7 is located behind the capacitive sensing network 6. A secondary capacitor 8 is disposed within the cantilever structure to form the low-voltage arm of the capacitor voltage divider circuit, and both ends of the secondary capacitor 8 are connected to a voltage-shielded twisted pair cable 9, which is disposed on the end face of the cantilever structure, outputting a secondary voltage signal to ensure high precision and strong anti-interference capability.

[0035] Specifically, the voltage-shielded twisted pair cable 9 is a two-core shielded cable, with the two cores twisted together to form a twisted pair. The twisted pair has an outer metal braided mesh as a shielding layer. The two ends of the secondary capacitor 8 are connected to the two cores at one end of the voltage-shielded twisted pair cable 9. The shielding layer is connected to the grounding terminal 11 via the shielding wire 12. The grounding terminal 11 is located on the end face of the cantilever structure. The capacitor sensing mesh 6 is connected to the capacitor terminal 10 via a lead wire. The capacitor terminal 10 is located on the end face of the cantilever structure and can output capacitance. See [link to relevant documentation]. Figure 4 As shown.

[0036] The outer wall of the conductive rod 5 and the inner wall of the capacitive sensing mesh 6 form two parallel capacitor plates, with an epoxy resin shell 1 between the two plates, constituting a capacitor for monitoring the state of the epoxy resin insulating medium. The signal of this capacitor can be measured at the capacitor terminal 10.

[0037] In this embodiment of the invention, the voltage measurement module employs the principle of a capacitive voltage divider. The primary voltage is divided into a lower intermediate voltage by a primary ceramic capacitor 7, and then converted into a standard secondary voltage output by a secondary capacitor 8. (See [reference]). Figure 5 As shown. The voltage measurement module utilizes a primary ceramic capacitor 7 fixed on a conductive rod 5 to form a primary capacitor, which, together with the secondary capacitor 8, performs voltage division to output a secondary voltage signal. This signal is transmitted through a voltage-shielded twisted-pair cable 9, providing strong anti-interference capabilities and high product accuracy. See [reference needed]. Figure 6 As shown.

[0038] All parts are encapsulated in epoxy resin shell 1, thus integrating the voltage transformer and capacitor status monitoring bushing together, which facilitates installation and occupies less space; the internal components are arranged in an orderly manner to avoid electromagnetic interference, and the output voltage signal is small and does not interfere with each other, resulting in superior performance.

[0039] This utility model integrates voltage measurement and capacitor status monitoring functions, with a highly compact structure. It can directly replace the standard bushings in equipment such as ring main units for installation, and is particularly suitable for the automation transformation of compact ring main units with limited space. It solves the problems of difficult installation and high cost of traditional instrument transformers.

[0040] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. An integrated bushing-type electronic voltage transformer characterized by, The conductive rod, the voltage measurement module, the capacitance monitoring module and the insulation and packaging structure are arranged on the center axis of the insulation and packaging structure. The voltage measurement module comprises a primary ceramic capacitor and a secondary capacitor. The capacitance monitoring module comprises a capacitance induction net. The insulation and packaging structure is an epoxy resin shell formed by curing the epoxy resin insulation material.

2. The integrated bushing-type electronic voltage transformer according to claim 1, characterized in that, The conductive rod is made of conductive metal.

3. The integrated bushing-type electronic voltage transformer of claim 1, wherein, The epoxy resin shell comprises a conical body, a flange plate and a cylindrical body arranged in sequence from front to back.

4. The integrated bushing-type electronic voltage transformer according to claim 3, characterized in that, The primary ceramic capacitor is arranged in the cylindrical body to form a high-voltage arm of a capacitance voltage divider circuit.

5. The integrated bushing-type electronic voltage transformer according to claim 4, characterized in that, The secondary capacitor is arranged in the cantilever structure to form a low-voltage arm of the capacitance voltage divider circuit.

6. The integrated bushing-type electronic voltage transformer of claim 3, wherein, The voltage shielded twisted pair cable is a two-core shielded cable, and the two cores are twisted with each other. The capacitance induction net is connected to a capacitance terminal through a lead wire.

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