A high voltage shielding device for a primary coil of a voltage transformer

Abstract

The application discloses a high-voltage shielding device for a primary coil of a voltage transformer, and relates to the technical field of high-voltage shielding devices.The high-voltage shielding device comprises a box body, an iron core fixedly sleeved in the box body, a primary winding fixedly sleeved at the top of the iron core, and a secondary winding fixedly sleeved at the bottom of the iron core.A first shielding assembly is arranged.When the high-voltage shielding of the primary coil of the voltage transformer is performed, a first clamping sleeve and a second clamping sleeve are sleeved outside the primary winding and a first bolt is rotated, so that the first bolt drives the first clamping sleeve and the second clamping sleeve to be tightly clamped and fixed outside the primary winding, thereby achieving the effect of a threaded hole combination.At this time, a closed pipe is threadedly sleeved in the threaded hole, thereby achieving the effect of gap sealing of the primary winding, that is, the effect of sealing of a lead-out head of the primary coil and a corner gap is achieved, the problem that the primary coil forms an electric field concentration point and leads to excessive partial discharge is avoided, and the high-voltage shielding effect of the primary coil is improved.

Description

Technical Field

[0001] This invention relates to the field of high-voltage shielding, specifically to a high-voltage shielding device for the primary coil of a voltage transformer. Background Technology

[0002] Voltage transformers are similar to transformers in that they are instruments used to transform voltage. However, transformers transform voltage to facilitate the transmission of electrical energy, so their capacity is very large, usually measured in kilovolt-amperes (kVA) or megavolt-amperes (MVA). Voltage transformers, on the other hand, transform voltage primarily to power measuring instruments and relay protection devices. They are used to measure line voltage, power, and electrical energy, or to protect valuable equipment, motors, and transformers in the event of a line fault. Therefore, voltage transformers have a very small capacity, typically only a few volt-amperes (VVA) or tens of VVA, with a maximum of no more than one kVA. As key metering and protection equipment in power systems, voltage transformers are widely used in substations, power plants, and high-voltage switchgear, undertaking the important task of proportionally converting high voltage to low voltage. The primary coil, as the core component directly receiving the system voltage, has its electric field distribution uniformity directly affecting the transformer's insulation performance and measurement accuracy. Currently, the high-voltage shielding structure of traditional voltage transformer coils mainly adopts electrostatic shields, capacitive voltage dividers, and surface coating of insulating cylinders.

[0003] However, when using electrostatic shielding for high-voltage shielding, due to technological limitations, it is difficult to achieve seamless wrapping, especially at lead wire exits and corners, where electric field concentration points are easily formed, leading to excessive partial discharge. When using capacitive voltage division for high-voltage shielding, the uniformity of the dielectric constant of the insulating material is extremely important; even slight carelessness can lead to uneven voltage distribution, making the manufacturing process of capacitive voltage division extremely complex and difficult to promote. When using insulating cylinder surface coating for high-voltage shielding, the semi-conductive coating is prone to peeling off under alternating hot and cold temperatures and mechanical vibrations, losing its shielding effectiveness. Furthermore, if there are tiny air gaps between the coating and the insulating cylinder, surface discharge can easily occur, becoming weak points in the insulation, resulting in poor high-voltage shielding stability. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a high-voltage shielding device for the primary coil of a voltage transformer.

[0005] To solve the above-mentioned technical problems, the present invention provides a high-voltage shielding device for the primary coil of a voltage transformer, comprising a housing, an iron core fixedly sleeved inside the housing, a primary winding fixedly sleeved on the top of the iron core, a secondary winding fixedly sleeved on the bottom of the iron core, a first shielding component disposed inside the housing, a second shielding component disposed on the top of the housing, and a sealing component disposed on the side of the housing.

[0006] Preferably, the first shielding component includes a first clamping sleeve, which is movably sleeved on the outside of the primary winding. A second clamping sleeve is movably sleeved on the side of the first clamping sleeve. A first bolt is sleeved on the side of the first clamping sleeve. A threaded hole is opened at the top of the first clamping sleeve. A closed tube is threaded into the inside of the threaded hole. A support tube is fixedly sleeved on the top of the closed tube. The material of the first clamping sleeve is the same as that of the second clamping sleeve, and the material of the first clamping sleeve is aluminum alloy.

[0007] Preferably, the second shielding component includes a sealing tube, which is fixedly sleeved on the top of the housing and outside the closed tube. A ceramic sleeve is fixedly sleeved on the outside of the sealing tube, and there are multiple ceramic sleeves evenly distributed outside the sealing tube.

[0008] Preferably, the sealing assembly includes a sealing cap, which is fixedly sleeved on the side of the housing. A No. 2 bolt is threaded into the internal thread of the sealing cap. A sealing ring is fixedly sleeved on the side of the sealing cap and is movably sleeved on the side of the housing. The sealing ring is made of rubber.

[0009] Preferably, an insulating sleeve is fixedly fitted to the outside of the primary winding. The insulating sleeve is adapted to the primary winding and is fitted to the outside of the iron core. The insulating sleeve is made of polyimide material.

[0010] Preferably, a protective component is provided inside the sealing tube. The protective component includes a high-voltage capacitor bank, which is fixedly installed inside the sealing tube. A medium-voltage capacitor bank is also fixedly installed inside the sealing tube, and the medium-voltage capacitor bank is located directly below the high-voltage capacitor bank.

[0011] Preferably, the top of the sealing tube is threaded with an oil tank, the front of the oil tank is conical, and the oil tank is made of electric porcelain material. There are two oil tanks.

[0012] Preferably, the oil tank is equipped with a maintenance component, which includes a float level monitor. The float level monitor is fixedly installed inside the oil tank. A viewing plate is fixedly sleeved on the side of the oil tank. The viewing plate is located in the center of the side of the float level monitor. An oil filling valve is installed on the top of the oil tank.

[0013] The beneficial effects of this invention are as follows: (1) By setting up the No. 1 shielding component, when the primary coil of the transformer is shielded at high voltage, the No. 1 clamping sleeve and the No. 2 clamping sleeve are connected to the outside of the primary winding and the No. 1 bolt is rotated so that the No. 1 bolt can drive the No. 1 clamping sleeve and the No. 2 clamping sleeve to be tightly clamped and fixed to the outside of the primary winding, thereby achieving the effect of threaded hole combination. At this time, the closed pipe thread is connected to the inside of the threaded hole, thereby achieving the sealing effect of the primary winding gap, that is, achieving the sealing effect of the primary coil lead head and corner gap, avoiding the formation of electric field concentration point in the primary coil, which leads to the problem of excessive partial discharge, thereby improving the high voltage shielding effect of the primary coil. (2) By setting an insulating sleeve, when the primary coil of the current transformer is wound, the insulating sleeve is attached to the outside of the coil, so that the insulating sleeve can completely seal and shield the coil, avoiding the problem of peeling off under alternating hot and cold and mechanical vibration when the insulating material coating on the coil surface is applied, thereby improving the stability of the coil insulation shielding. (3) By setting up maintenance components, when voltage transformer inspection and maintenance are required, the float liquid level monitor can detect the amount of oil inside the sealing tube in real time, which avoids the risk of breakdown due to poor internal insulation when the amount of oil inside the sealing tube is low, thus bringing convenience to the inspection and maintenance of voltage transformer. (4) By setting up protective components, when the voltage transformer is assembled, the high voltage capacitor group and the medium voltage capacitor group are fixedly installed inside the sealed tube, so that the high voltage capacitor group and the medium voltage capacitor group can provide voltage division protection for the coil leads, thereby avoiding the problem of breakdown when the electric field inside the coil is concentrated, which could lead to danger to the staff, thus improving the safety of the voltage transformer during operation. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a preferred embodiment of a high-voltage shielding device for the primary coil of a voltage transformer according to the present invention; Figure 2 This is a bottom view of the present invention; Figure 3 This is a side view of the housing in this invention; Figure 4 This is a front view of the iron core in this invention; Figure 5 This is a side view of the iron core in this invention; Figure 6 This is a front view of the No. 1 clamping sleeve in this invention; Figure 7 This is a cross-sectional view of the sealing tube in this invention.

[0015] The names of the components corresponding to the markings in the above attached figures are as follows: 101, housing; 102, iron core; 103, primary winding; 104, secondary winding; 105, insulating sleeve; 106, oil tank; 201, clamping sleeve No. 1; 202, clamping sleeve No. 2; 203, bolt No. 1; 204, threaded hole; 205, sealing tube; 206, support tube; 301, sealing tube; 302, porcelain sleeve; 401, sealing cover; 402, bolt No. 2; 403, sealing ring; 501, high-voltage capacitor bank; 502, medium-voltage capacitor bank; 601, float level monitor; 602, transparent plate; 603, oil filling valve. Detailed Implementation

[0016] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0017] like Figures 3-7 As shown, the present invention provides a high-voltage shielding device for the primary coil of a voltage transformer, comprising a housing 101, an iron core 102 fixedly sleeved inside the housing 101, a primary winding 103 fixedly sleeved on the top of the iron core 102, and a secondary winding 104 fixedly sleeved on the bottom of the iron core 102. A first shielding assembly is disposed inside the housing 101, a second shielding assembly is disposed on the top of the housing 101, and a sealing assembly is disposed on the side of the housing 101. The first shielding assembly includes a first clamping sleeve 201, which is movably sleeved outside the primary winding 103. A second clamping sleeve 202 is movably sleeved on the side of the first clamping sleeve 201. A first bolt 203 is sleeved on the side of the first clamping sleeve 201. A threaded hole 204 is opened on the top of the first clamping sleeve 201, and a sealing tube 205 is threadedly sleeved inside the threaded hole 204. A bolt 203 is fixedly sleeved on the top of the sealing tube 205. The support tube 206 and the first clamping sleeve 201 are made of the same material as the second clamping sleeve 202, with the first clamping sleeve 201 being made of aluminum alloy. By setting the first shielding component, when performing high-voltage shielding of the primary coil of the transformer, the first clamping sleeve 201 and the second clamping sleeve 202 are fitted onto the outside of the primary winding 103, and the first bolt 203 is rotated. This allows the first bolt 203 to drive the first clamping sleeve 201 and the second clamping sleeve 202 to be tightly clamped and fixed to the outside of the primary winding 103, thus achieving the combined effect of the threaded hole 204. At this time, the sealing tube 205 is threaded into the inside of the threaded hole 204, thereby achieving the sealing effect of the gaps in the primary winding 103, that is, achieving the sealing effect of the primary coil lead outlet and corner gaps. This avoids the formation of electric field concentration points in the primary coil, which leads to excessive partial discharge, thereby improving the high-voltage shielding effect of the primary coil.

[0018] like Figures 1-3As shown, the second shielding assembly includes a sealing tube 301, which is fixedly sleeved on the top of the housing 101 and also fixedly sleeved on the outside of the closed tube 205. A porcelain sleeve 302 is fixedly sleeved on the outside of the sealing tube 301. There are multiple porcelain sleeves 302, which are evenly distributed on the outside of the sealing tube 301. By setting the second shielding assembly, when performing high-voltage shielding of the primary winding 103, the sealing tube 301 is sealed and welded to the top of the housing 101, so that the sealing tube 301 and the porcelain sleeve 302 can seal and shield the support tube 206, thereby achieving the high-voltage shielding effect of the lead wire of the primary winding 103.

[0019] like Figure 3 As shown, the sealing assembly includes a sealing cover 401, which is fixedly fitted onto the side of the housing 101. A second bolt 402 is threaded into the internal thread of the sealing cover 401. A sealing ring 403 is fixedly fitted onto the side of the sealing cover 401 and movably fitted onto the side of the housing 101. The sealing ring 403 is made of rubber. By setting up the sealing assembly, when the primary coil of the current transformer is shielded against high voltage, the sealing cover 401 is fitted onto the side of the housing 101 and the second bolt 402 is rotated. This allows the second bolt 402 to drive the sealing ring 403 through the sealing cover 401 to press and fix it onto the side of the housing 101, thereby achieving a sealing effect on the housing 101. This avoids the problem of leakage of internal insulating oil when the gaps in the housing 101 are large, thus improving the sealing effect inside the current transformer.

[0020] like Figures 4-5 As shown, an insulating sleeve 105 is fixedly sleeved on the outside of the primary winding 103. The insulating sleeve 105 is adapted to the primary winding 103 and is sleeved on the outside of the iron core 102. The insulating sleeve 105 is made of polyimide material. By setting the insulating sleeve 105, when the primary coil of the current transformer is wound, the insulating sleeve 105 is sleeved on the outside of the coil, so that the insulating sleeve 105 can completely seal and shield the coil, avoiding the problem of peeling off under alternating cold and heat and mechanical vibration when the insulating material coating on the coil surface is applied, thereby improving the stability of the coil insulation shielding.

[0021] like Figure 7As shown, a protective assembly is provided inside the sealing tube 301. The protective assembly includes a high-voltage capacitor bank 501, which is fixedly installed inside the sealing tube 301. A medium-voltage capacitor bank 502 is also fixedly installed inside the sealing tube 301, located directly below the high-voltage capacitor bank 501. By setting up the protective assembly, when the voltage transformer is assembled, the high-voltage capacitor bank 501 and the medium-voltage capacitor bank 502 are respectively fixedly installed inside the sealing tube 301, so that the high-voltage capacitor bank 501 and the medium-voltage capacitor bank 502 can provide voltage division protection for the coil leads. This avoids breakdown when the electric field inside the coil is concentrated, which could lead to danger to the staff, thereby improving the safety of the voltage transformer during operation.

[0022] like Figure 1-3 and Figure 7 As shown, an oil tank 106 is threaded onto the top of the sealing tube 301. The front of the oil tank 106 is conical, and the material of the oil tank 106 is electrical porcelain. There are two oil tanks 106. By setting up the oil tank 106, when filling or maintaining the insulating oil inside the voltage transformer, the oil tank 106 can be rotated to remove the oil tank 106 from the top of the sealing tube 301. That is, the top of the sealing tube 301 is opened, which facilitates the filling and discharge of insulating oil through the top of the sealing tube 301, thus bringing convenience to the maintenance of the voltage transformer.

[0023] like Figure 7 As shown, a maintenance assembly is installed inside the oil tank 106. The maintenance assembly includes a float level monitor 601, which is fixedly installed inside the oil tank 106. A viewing plate 602 is fixedly sleeved on the side of the oil tank 106, and the viewing plate 602 is located in the center of the side of the float level monitor 601. An oil filling valve 603 is installed on the top of the oil tank 106. By setting up the maintenance assembly, when the voltage transformer needs to be inspected and maintained, the float level monitor 601 can detect the oil level inside the sealing tube 301 in real time. This avoids the risk of breakdown due to poor internal insulation when the oil level inside the sealing tube 301 is low, thus bringing convenience to the inspection and maintenance of the voltage transformer.

[0024] The working principle of this invention is as follows: When performing high-voltage shielding of the primary coil of the transformer, clamping sleeve 201 and clamping sleeve 202 are fitted onto the outside of the primary winding 103, and bolt 203 is rotated. This allows bolt 203 to drive clamping sleeve 201 and clamping sleeve 202 to tightly clamp and fix them onto the outside of the primary winding 103, thus achieving the combined effect of threaded hole 204. At this time, sealing tube 205 is threaded into the inside of threaded hole 204, thereby achieving the sealing effect of the gaps in the primary winding 103, that is, achieving the sealing effect of the lead wire protrusion and corner gaps of the primary coil. This avoids the formation of electric field concentration points in the primary coil, which leads to excessive partial discharge, thereby improving efficiency. To improve the high-voltage shielding effect of the primary winding, during the high-voltage shielding of the primary winding 103, the sealing tube 301 is welded to the top of the housing 101, allowing the sealing tube 301 and the porcelain sleeve 302 to seal and shield the support tube 206, thus achieving the high-voltage shielding effect of the lead-out end of the primary winding 103. During the high-voltage shielding of the transformer's primary winding, the sealing cover 401 is fitted onto the side of the housing 101, and the second bolt 402 is rotated. This allows the second bolt 402 to drive the sealing ring 403 to be pressed and fixed to the side of the housing 101 through the sealing cover 401, achieving a sealing effect for the housing 101 and preventing the internal insulating oil from leaking out when there are large gaps in the housing 101. To address leakage issues and improve the sealing effect inside the transformer, when the primary coil of the transformer is wound, the insulating sleeve 105 is fitted over the outside of the coil, allowing the insulating sleeve 105 to completely seal and shield the coil. This avoids the problem of peeling off the insulation material coating on the coil surface due to temperature changes and mechanical vibration, thus improving the stability of the coil insulation shielding. When assembling the voltage transformer, the high-voltage capacitor group 501 and the medium-voltage capacitor group 502 are respectively fixedly installed inside the sealing tube 301. This allows the high-voltage capacitor group 501 and the medium-voltage capacitor group 502 to provide voltage division protection for the coil leads, preventing breakdown caused by concentrated electric field inside the coil, which could lead to danger to personnel. This addresses the issue of oil level monitoring, thereby improving the safety of voltage transformer operation. When filling or maintaining the insulating oil inside the voltage transformer, the oil tank 106 is rotated, allowing it to be removed from the top of the sealing tube 301. This opens the top of the sealing tube 301, facilitating the filling and draining of insulating oil through the top of the sealing tube 301, thus providing convenience for voltage transformer maintenance. When voltage transformer inspection and maintenance are required, the float level monitor 601 can detect the oil level inside the sealing tube 301 in real time, avoiding the risk of breakdown due to poor internal insulation caused by insufficient oil level inside the sealing tube 301, thus facilitating the inspection and maintenance of the voltage transformer.

[0025] It should be noted that the present invention is not limited to the specific structure shown in the accompanying drawings in the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art.

Claims

1. A high-voltage shielding device for the primary coil of a voltage transformer, characterized in that, The enclosure includes a housing (101), inside which an iron core (102) is fixedly fitted. A primary winding (103) is fixedly fitted to the top of the iron core (102), and a secondary winding (104) is fixedly fitted to the bottom of the iron core (102). An insulating sleeve (105) is fixedly fitted to the outside of the primary winding (103). A first shielding assembly is provided inside the housing (101). The first shielding assembly includes a first clamping sleeve (201) and a second clamping sleeve (202) movably fitted outside the primary winding (103). A screw is provided on the top of the first clamping sleeve (201). The threaded hole (204) has a closed tube (205) threaded inside. The top of the box (101) is provided with a second shielding assembly. The second shielding assembly includes a sealing tube (301) fixedly sleeved on the top of the box (101). The sealing tube (301) is fixedly sleeved on the outside of the closed tube (205). A high-voltage capacitor group (501) and a medium-voltage capacitor group (502) are fixedly installed inside the sealing tube (301). The medium-voltage capacitor group (502) is located directly below the high-voltage capacitor group (501). The side of the box (101) is provided with a sealing assembly.

2. The high-voltage shielding device for the primary coil of a voltage transformer according to claim 1, characterized in that: The first clamping sleeve (201) has a first bolt (203) sleeved on its side. The first bolt (203) is used to drive the first clamping sleeve (201) and the second clamping sleeve (202) to be tightly clamped and fixed outside the primary winding (103). The top of the closed tube (205) is fixedly sleeved with a support tube (206). The first clamping sleeve (201) and the second clamping sleeve (202) are both made of aluminum alloy.

3. The high-voltage shielding device for the primary coil of a voltage transformer according to claim 1, characterized in that: The sealing tube (301) is fixedly fitted with a ceramic sleeve (302), and there are multiple ceramic sleeves (302) evenly distributed on the outside of the sealing tube (301).

4. The high-voltage shielding device for the primary coil of a voltage transformer according to claim 1, characterized in that: The sealing assembly includes a sealing cover (401), which is fixedly sleeved on the side of the housing (101). A No. 2 bolt (402) is threaded into the inside of the sealing cover (401). A sealing ring (403) is fixedly sleeved on the side of the sealing cover (401). The sealing ring (403) is movably sleeved on the side of the housing (101). The sealing ring (403) is made of rubber.

5. A high-voltage shielding device for the primary coil of a voltage transformer according to claim 1, characterized in that: The insulating sleeve (105) is adapted to the primary winding (103) and is sleeved on the outside of the iron core (102). The insulating sleeve (105) is made of polyimide material.

6. The high-voltage shielding device for the primary coil of a voltage transformer according to claim 1, characterized in that: The top of the sealing tube (301) is threaded with an oil tank (106). The front of the oil tank (106) is conical, and the material of the oil tank (106) is electric porcelain material. There are two oil tanks (106).

7. A high-voltage shielding device for the primary coil of a voltage transformer according to claim 6, characterized in that: The oil tank (106) is equipped with a maintenance component, which includes a float level monitor (601). The float level monitor (601) is fixedly installed inside the oil tank (106). A viewing plate (602) is fixedly sleeved on the side of the oil tank (106). The viewing plate (602) is located in the center of the side of the float level monitor (601). An oil filling valve (603) is installed on the top of the oil tank (106).

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