10kv pole-mounted full-insulated metering voltage transformer

Abstract

The utility model belongs to power system transmission and distribution technical field discloses a kind of 10kV post full insulation measurement voltage mutual inductor, including insulation core body;Primary wiring system, primary wiring system includes full insulation seal shell, full insulation seal shell and form the chamber of completely closed high-voltage live body, and full insulation seal shell is equipped with rotary compression type terminal lug;Secondary wiring box, secondary wiring box is installed in the bottom of insulation core body, and secondary wiring box is connected with the low-voltage end of insulation core body by internal wire;Mounting bracket, long circular fixing hole is opened in mounting bracket.The utility model can completely isolate high-voltage terminal and external environment under the synergistic effect of epoxy resin vacuum casting insulation core body, full-closed seal shell and sealed secondary wiring box, to solve the security risk of traditional semi-insulating structure due to the exposure of A end, such as insulation deterioration, pollution flashover, animal electric shock, can significantly improve the long-term reliability of equipment in humid and dirty area.

Description

Technical Field

[0001] This utility model relates to the field of power system transmission and distribution technology, and in particular to a 10kV pole-mounted fully insulated metering voltage transformer. Background Technology

[0002] Voltage transformers (PTs) are important devices in power systems for energy metering, voltage measurement, and protection. 10kV pole-mounted voltage transformers are usually installed on power poles and directly connected to high-voltage lines to provide metering signals to the distribution transformers or users below.

[0003] Currently, traditional 10kV pole-mounted voltage transformers mostly adopt a semi-insulated structure, that is, the high-voltage terminal (A end) of the primary winding is exposed to the air and is kept insulated from the grounding base (N end) by an insulator. This structure has insulation risk problems. Specifically, the exposed high-voltage terminal is susceptible to external environmental factors such as dust, moisture, salt spray, and small animals, which leads to a decrease in insulation performance. Therefore, we propose a 10kV pole-mounted fully insulated metering voltage transformer. Utility Model Content

[0004] In view of the insulation risk problem of the existing voltage transformers, this utility model is proposed.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution: A 10kV pole-mounted fully insulated metering voltage transformer includes an insulating core, wherein the insulating core is set using an epoxy resin vacuum casting process. A primary wiring system includes a fully insulated sealed cover installed on top of the insulating core, the fully insulated sealed cover forming a chamber that completely encloses the high-voltage live parts, and a rotary clamping terminal piece is installed on the fully insulated sealed cover, and the rotary clamping terminal piece is electrically connected to the external line. A secondary junction box is installed at the bottom of the insulating core, and the secondary junction box is connected to the low-voltage end of the insulating core through internal wires; The mounting bracket is installed at the bottom of the secondary junction box, and the mounting bracket has symmetrically arranged elongated oval fixing holes for fixing.

[0006] As a technical solution for a 10kV pole-mounted fully insulated metering voltage transformer described in this utility model, the fully insulated sealing shell is made of weather-resistant engineering plastic and is detachably fixed to the insulating core by bolts.

[0007] As a technical solution for a 10kV pole-mounted fully insulated metering voltage transformer described in this utility model, the secondary junction box is integrally cast with epoxy resin to form a sealed structure.

[0008] As a technical solution for a 10kV pole-mounted fully insulated metering voltage transformer described in this utility model, the secondary junction box is provided with multiple sets of terminals arranged in parallel, and each set of terminals is separated by an insulating partition.

[0009] As a technical solution for a 10kV pole-mounted fully insulated metering voltage transformer according to this utility model, the mounting bracket is an L-shaped structure with a vertical part and a horizontal part. The vertical part and the horizontal part are integrally formed. The vertical part is installed at the bottom of the secondary junction box, and the oblong fixing hole is located on the horizontal part.

[0010] As a technical solution for a 10kV pole-mounted fully insulated metering voltage transformer described in this utility model, the mounting bracket is made of galvanized steel plate with a thickness of 3≥mm, and the surface of the mounting bracket is passivated to form a rust-proof layer.

[0011] Compared with the prior art, the present invention has at least the following beneficial effects: 1. This utility model, through the synergistic effect of epoxy resin vacuum casting insulating core, fully enclosed sealed cover and sealed secondary junction box, can completely isolate high-voltage terminals from the external environment, thereby solving the safety hazards of insulation deterioration, flashover and animal electric shock caused by the exposure of the A terminal in traditional semi-insulated structures, and can significantly improve the long-term reliability of equipment in humid and dirty areas.

[0012] 2. This utility model simplifies the high-altitude operation process by rotating and pressing the terminal block in conjunction with the mounting bracket with an elongated oval fixing hole. At the same time, the detachable fully enclosed sealing cover and rust-proof mounting bracket can reduce the life cycle cost. Combined with the terminal insulation plate and electromagnetic isolation design, it can reduce signal interference and ensure measurement accuracy. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them: Figure 1 This is a schematic diagram of the main structure of this utility model.

[0014] Figure 2 For the present utility model Figure 1 Enlarged structural diagram at point A in the middle.

[0015] Figure 3 This is a side view of the structure of this utility model.

[0016] Explanation of reference numerals in the attached figures: In the diagram: 1. Insulating core; 201. Fully insulated sealed cover; 202. Rotary clamping connector; 3. Secondary junction box; 4. Mounting bracket; 401. Vertical part; 402. Horizontal part; 403. Oblong fixing hole. Detailed Implementation

[0017] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0018] Reference Figures 1-3 This invention provides a 10kV pole-mounted fully insulated metering voltage transformer, which includes an insulating core 1. The insulating core 1 is constructed using an epoxy resin vacuum casting process. The epoxy resin is vacuum cast at a temperature controlled at 45±5℃ and a vacuum degree ≤0.1MPa. After curing, it forms a solid insulator without bubbles or cracks. Its internal structure consists of a primary winding (high voltage side) and a secondary winding (low voltage side) wound in layers, with DMD insulating paper separating the layers to ensure a power frequency withstand voltage ≥42kV / 1min. This improves the overall mechanical strength and weather resistance, and prevents moisture intrusion that could lead to insulation degradation. The primary wiring system is installed on the top of the insulating core 1 with a fully insulated sealed cover 201, which forms a completely enclosed chamber for the high-voltage live conductor. A rotary clamping connector 202 is installed on the fully insulated sealed cover 201 and is electrically connected to the external line. The rotary clamping connector 202 is made of T2 tin-plated copper and can lock a 10-25mm² conductor by rotating it 90° clockwise. The torque is set to 25 N·m. The fully insulated sealed cover 201 can completely enclose the high-voltage live conductor (such as end A) and prevent short circuits or creepage accidents caused by dust, moisture, or small animals. At the same time, the rotary clamping connector 202 can simplify the installation process of high-voltage lines and ensure contact reliability and operational safety. Secondary junction box 3 is installed at the bottom of insulating core 1, and secondary junction box 3 is connected to the low voltage end of insulating core 1 through internal wires. The bottom connection design of secondary junction box 3 can separate high and low voltage circuits and reduce the impact of electromagnetic interference on measurement accuracy. Mounting bracket 4 is installed at the bottom of secondary junction box 3. Mounting bracket 4 has symmetrically arranged elongated oval fixing holes 403 for fixing. The diameter of the elongated oval fixing holes 403 is 12×20mm (long axis), allowing ±10mm of installation position adjustment. The design of the elongated oval fixing holes 403 is to accommodate the hole spacing deviation of different mounting brackets 4, improving the flexibility of on-site installation.

[0019] Reference Figures 1-3 The fully insulated sealed housing 201 is made of weather-resistant engineering plastic and is detachably fixed to the insulating core 1 by bolts. It is made of weather-resistant PA66 engineering plastic (UV resistance rating ≥UV8). The inner wall of the fully insulated sealed housing 201 has a pre-embedded conductive shielding layer and is grounded. In application, the weather-resistant engineering plastic fully insulated sealed housing 201 has UV resistance and corrosion resistance to extend its outdoor service life (compared to traditional ceramic insulators). At the same time, the detachable bolt fixing method facilitates maintenance or replacement of high-voltage wiring components and reduces operation and maintenance costs.

[0020] Reference Figure 1 and Figure 3 The secondary junction box 3 is integrally cast with epoxy resin to form a sealed structure. In application, the integral casting of the secondary junction box 3 with epoxy resin can completely seal the secondary terminals and prevent moisture from corroding the terminals or causing measurement errors.

[0021] Reference Figure 1 and Figure 3 The secondary junction box 3 contains multiple sets of terminals arranged in parallel, with each set of terminals separated by an insulating partition. The secondary junction box 3 is integrally cast with epoxy resin, and the internal terminal blocks are pre-fixed in the mold. After casting, it achieves an IP67 protection rating. Each set of terminals is separated by a fiberglass reinforced insulating partition with a thickness of ≥2mm, and the terminal spacing is ≥15mm to comply with the IEC 61869 standard. In application, the insulating partition design separates the terminals, which can prevent multiple sets of secondary cables from accidentally short-circuiting and ensure the independence and accuracy of the metering signal.

[0022] Reference Figure 1 and Figure 3 The mounting bracket 4 has an L-shaped structure with a vertical part 401 and a horizontal part 402. The vertical part 401 and the horizontal part 402 are integrally formed. The vertical part 401 is installed at the bottom of the secondary junction box 3, and the oblong fixing hole 403 is provided on the horizontal part 402. In application, the L-shaped mounting bracket 4 and the oblong fixing hole 403 are designed to provide stable support and adapt to the problem of uneven mounting surface of the pole / crossarm.

[0023] Reference Figure 1 and Figure 3The mounting bracket 4 is made of galvanized steel plate with a thickness of ≥3mm, and the surface of the mounting bracket 4 is passivated to form a rust-proof layer (chromate film, salt spray resistance ≥500h). In application, the galvanized steel plate and passivation treatment design improve the corrosion resistance and are suitable for harsh environments such as high humidity and salt spray.

[0024] The working principle of this utility model is as follows: Installation stage: First, use an insulated rope to vertically hoist the voltage transformer, and ensure that the horizontal part 402 of the mounting bracket 4 is in contact with the crossarm of the pole, and fix it with M12 stainless steel bolts through the elongated fixing hole 403 with a torque of 50 N·m; High-voltage wiring: Disconnect the power supply to the line, test for voltage, connect the grounding wire, then strip 15mm of the insulation layer of the conductor, connect the rotating clamping terminal 202, and rotate clockwise to the locked position; Secondary wiring: Use a tool (such as a screwdriver) to open the protective cover of the secondary junction box 3, and then connect the meter wire to the 1a-1n terminal group (corresponding to phase A), and connect the protection device wire to the 2a-2n terminal group (the wire needs to be run across the partition); Maintenance process: Inspect the fully insulated sealed cover 201 annually for cracks and the rotary clamping connector 202 for overheating and discoloration. If a fault occurs, repair or replace the damaged parts.

[0025] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A 10kV pole-mounted fully insulated metering voltage transformer, characterized in that: include: Insulating core (1), wherein the insulating core (1) is set by epoxy resin vacuum casting process; A primary wiring system includes a fully insulated sealed cover (201) installed on the top of the insulating core (1), the fully insulated sealed cover (201) forming a completely enclosed chamber of the high-voltage live body, a rotary clamping terminal piece (202) installed on the fully insulated sealed cover (201), and the rotary clamping terminal piece (202) is electrically connected to the external line; Secondary junction box (3), the secondary junction box (3) is installed at the bottom of the insulating core (1), and the secondary junction box (3) is connected to the low voltage end of the insulating core (1) through internal wires; Mounting bracket (4) is installed at the bottom of the secondary junction box (3). The mounting bracket (4) has symmetrically arranged elongated fixing holes (403) for fixing.

2. The 10kV pole-mounted fully insulated metering voltage transformer according to claim 1, characterized in that: The fully insulated sealing cover (201) is made of weather-resistant engineering plastic and is detachably fixed to the insulating core (1) by bolts.

3. The 10kV pole-mounted fully insulated metering voltage transformer according to claim 1, characterized in that: The secondary junction box (3) is integrally cast with epoxy resin and forms a sealed structure.

4. The 10kV pole-mounted fully insulated metering voltage transformer according to claim 1, characterized in that: The secondary junction box (3) is provided with multiple sets of terminals arranged in parallel, and each set of terminals is separated by an insulating partition.

5. The 10kV pole-mounted fully insulated metering voltage transformer according to claim 1, characterized in that: The mounting bracket (4) is an L-shaped structure consisting of a vertical part (401) and a horizontal part (402). The vertical part (401) and the horizontal part (402) are integrally formed. The vertical part (401) is installed at the bottom of the secondary junction box (3), and the oblong fixing hole (403) is located on the horizontal part (402).

6. The 10kV pole-mounted fully insulated metering voltage transformer according to claim 5, characterized in that: The mounting bracket (4) is made of galvanized steel plate with a thickness of ≥3mm, and the surface of the mounting bracket (4) is passivated to form a rust-proof layer.

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