Cable connection device and transformer

Abstract

The application discloses a cable wiring device, which comprises a grounding device, a current transformer, a cable box and a connecting cable installed in the cable box. One end of the connecting cable is connected with a transformer winding lead cable, and the other end is connected with a line cable terminal. The outer side of the connecting cable is wrapped with an insulation layer. The current transformer is installed on the cable box, and the grounding device is used for grounding the current transformer and the cable box. In the cable wiring device, the cable box is installed on a transformer box body, the grounding safety of the cable wiring device is ensured through the grounding device, the measurement of the transformer load current and the overload protection are realized through the current transformer, one end of the connecting cable is connected with the transformer winding lead cable, and the other end is connected with the line cable terminal, so that the use of oil-oil sleeve pipes for transition is avoided, the multiple connection of the connecting cable is reduced, and the safety hidden danger of the transformer operation is reduced.

Description

Technical Field

[0001] This invention relates to the field of power transformer manufacturing technology, and particularly to a cable connection device. This invention also relates to a transformer including the aforementioned cable connection device. Background Technology

[0002] In transformers, such as large power transformers with a voltage of 110kV, when high-voltage side cable connections are used, due to the high voltage, oil-oil bushings are usually used when the high-voltage winding leads of the transformer pass through the transformer tank to help the transformer complete the installation of the current transformer and realize the measurement of the transformer load current and load protection.

[0003] Because oil-to-oil bushings are required for the transition, and the cables are connected multiple times, there are potential safety hazards in the operation of the transformer.

[0004] Therefore, how to reduce the safety hazards of transformer operation is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a cable connection device to reduce safety hazards in transformer operation. Another purpose of this invention is to provide a transformer including the above-mentioned cable connection device.

[0006] To achieve the above objectives, the present invention provides a cable connection device, including a grounding device, a current transformer, a cable box, and a connecting cable installed in the cable box. One end of the connecting cable is connected to the transformer winding lead cable, and the other end is connected to the line cable terminal. The outer side of the connecting cable is wrapped with an insulating layer. The current transformer is installed on the cable box, and the grounding device is used to ground the current transformer and the cable box.

[0007] Preferably, the cable box further includes a first sealing member and a second sealing member. The cable box is provided with a first mounting hole on the connecting cable for connecting to the transformer winding lead cable and a second mounting hole on the connecting cable for connecting to the line cable terminal. The first sealing member is used to open and close the first mounting hole, and the second sealing member is used to open and close the second mounting hole.

[0008] Preferably, the first mounting hole and the second mounting hole are hole structures of different shapes.

[0009] Preferably, it also includes a current transformer core ring and a transformer junction box, wherein the external wiring of the current transformer core ring is led to the transformer junction box.

[0010] Preferably, the cable bracket is disposed inside the cable box and is used to support the connecting cable.

[0011] Preferably, the cable support is a laminated paperboard.

[0012] Preferably, the current transformer is installed at the bottom of the cable box.

[0013] Preferably, the current transformer is provided with a valve body for injecting or draining oil into the cable box.

[0014] Preferably, when the cable box is sealed, oil is injected inside the cable box.

[0015] A transformer includes a cable connection device, wherein the cable connection device is any of the cable connection devices described above.

[0016] In the above technical solution, the cable connection device provided by the present invention includes a grounding device, a current transformer, a cable box and a connecting cable installed in the cable box. One end of the connecting cable is connected to the transformer winding lead cable and the other end is connected to the line cable terminal. The outside of the connecting cable is wrapped with an insulating layer. The current transformer is installed on the cable box. The grounding device is used to ground the current transformer and the cable box.

[0017] As described above, in the cable connection device provided in this application, the cable box is installed on the transformer box, the grounding device ensures the grounding safety of the cable connection device, the current transformer is used to measure the transformer load current and provide overload protection, one end of the connecting cable is connected to the transformer winding lead cable, and the other end is connected to the line cable terminal, avoiding the use of oil-oil bushings for transition, reducing multiple connections of the connecting cable, and reducing the safety hazards of transformer operation. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is an installation position diagram of the cable connection device provided in an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the cable connection device provided in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the cable box provided in an embodiment of the present invention;

[0022] Figure 4 for Figure 3 Side view of the cable box shown;

[0023] Figure 5 This is a schematic diagram of the current transformer provided in an embodiment of the present invention;

[0024] Figure 6 for Figure 5 The side view of the current transformer shown;

[0025] Figure 7 This is a schematic diagram of the connecting cable provided in an embodiment of the present invention;

[0026] Figure 8 for Figure 7 Enlarged view of section X of the connecting cable shown;

[0027] Figure 9 for Figure 7 Enlarged view of the Y section of the connecting cable shown;

[0028] Figure 10 This is a diagram showing the connection position between the connecting cable and the transformer winding lead cable provided in an embodiment of the present invention;

[0029] Figure 11 This is a diagram showing the connection position between the connecting cable and the line cable terminal provided in an embodiment of the present invention;

[0030] Figure 12 This is a schematic diagram of the structure of the first hanging member of the cable bracket provided in an embodiment of the present invention;

[0031] Figure 13 This is a schematic diagram of the structure of the second bracket of the cable bracket provided in an embodiment of the present invention;

[0032] Figure 14 This is a diagram showing the installation location of the grounding device provided in an embodiment of the present invention;

[0033] Figure 15 This is a schematic diagram of the transformer provided in an embodiment of the present invention.

[0034] in Figure 1-15 middle:

[0035] 1. Cable box; 2. Connecting cables;

[0036] 3. Cable bracket; 3-1. First mounting bracket; 3-2. First cable mounting groove; 3-3. Second mounting bracket; 3-4. Second cable mounting groove;

[0037] 4. First mounting hole; 5. Second mounting hole; 6. Current transformer; 7. Current transformer core ring; 8. Transformer junction box; 9. Ball valve; 10. Line cable terminal; 11. Bracket; 12. Transformer housing; 13. Transformer winding lead cable; 14. Grounding device; 15. Insulation layer. Detailed Implementation

[0038] The core of this invention is to provide a cable connection device to reduce safety hazards in transformer operation. Another core aspect of this invention is to provide a transformer that includes the aforementioned cable connection device.

[0039] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0040] Please refer to Figures 1 to 15 .

[0041] In one specific embodiment, the cable connection device provided by this invention includes a grounding device 14, a current transformer 6, a cable box 1, and a connecting cable 2 installed inside the cable box 1. The cable box 1 is installed on the side of the transformer housing 12, specifically by means of round flange bolts, eliminating the need for an oil-to-oil bushing transition.

[0042] To improve the installation stability of the cable connection device, the bottom of the cable box 1 is fixed to the side of the transformer box 12 by the bracket 11.

[0043] Cable box 1 can be made of Q235 steel plate, with rust removal and painting inside and out.

[0044] During assembly, the side flange of cable box 1 is connected to the flange of transformer housing 12, which is specifically the transformer tank. An upper flange can be installed at the top of cable box 1, and this upper flange is connected to a temporary testing device.

[0045] Specifically, the grounding device 14 consists of a stainless steel grounding nut and a 10mm² cable for grounding the user equipment casing.

[0046] Current transformer 6 is used to measure the load on the transformer.

[0047] One end of the connecting cable 2 is connected to the transformer winding lead cable 13, and the other end is connected to the line cable terminal 10. The outer side of the connecting cable 2 is wrapped with an insulation layer 15. Specifically, the insulation layer 15 can be made of insulating paper, and the wrapping thickness of the insulation layer 15 is matched with the voltage level.

[0048] The current transformer 6 is installed on the cable box 1. The grounding device 14 is used to ground the current transformer 6 and the cable box 1. Specifically, the end of the connecting cable 2 is connected to the line cable terminal 10 through a flange. The connecting cable 2 can be copper stranded wire, and its specifications are matched with the load current.

[0049] As can be seen from the above description, in the cable connection device provided in the specific embodiment of this application, the grounding device 14 ensures the grounding safety of the cable connection device, the current transformer 6 realizes the measurement of transformer load current and overload protection, and one end of the connecting cable 2 is connected to the transformer winding lead cable 13, and the other end is connected to the line cable terminal 10, avoiding the use of oil-oil bushing for transition, reducing the number of connections of the connecting cable 2, and reducing the safety hazards of transformer operation.

[0050] In one specific embodiment, the cable connection device further includes a first sealing member and a second sealing member. The cable box 1 is provided with a first mounting hole 4 on the connecting cable 2 for connecting to the transformer winding lead cable 13 and a second mounting hole 5 on the connecting cable 2 for connecting to the line cable terminal 10. The first sealing member is used to open and close the first mounting hole 4, and the second sealing member is used to open and close the second mounting hole 5. Specifically, the first mounting hole 4 and the second mounting hole 5 can be of the same shape. To facilitate timely identification of the installation structure at the end of the connecting cable 2, preferably, the first mounting hole 4 and the second mounting hole 5 have different hole shapes. Specifically, the first mounting hole 4 and the first sealing member form a round hand hole for connecting the transformer winding lead cable 13. The second mounting hole 5 and the second sealing member form a square hand hole for connecting the line cable terminal 10.

[0051] Specifically, the grounding device 14 is also used for the flange connection grounding of the transformer housing 12.

[0052] To improve the installation stability of the connecting cable 2, preferably, the cable wiring device also includes a cable bracket 3 disposed inside the cable box 1, which is used to support the connecting cable 2.

[0053] Specifically, the cable bracket 3 is made of laminated cardboard. The cable bracket 3, made of laminated cardboard, is used to clamp the cable connection and fix the cable 2. Specifically, the cable bracket 3 includes a first hanger 3-1 fixedly connected to the cable box 1 and a second hanger 3-3 connected to the first hanger 3-1. The first hanger 3-1 has a first cable mounting groove 3-2, and the second hanger 3-3 has a second cable mounting groove 3-4. After the first hanger 3-1 and the second hanger 3-3 are fixed, the first cable mounting groove 3-2 and the second cable mounting groove 3-4 cooperate to form a hole structure for clamping and connecting the cable 2. Specifically, the first hanger can be installed on the top of the cable box 1 to achieve top suspension of the connecting cable 2.

[0054] When connecting cable 2, open the round manhole of cable box 1, install cable bracket 3, and place the connecting cable 2 with insulation layer 15 inside cable box 1. Connecting cable 2 is installed on cable bracket 3, with one end bolted to transformer winding lead cable 13. After connection, insulate the connector with the same thickness as connecting cable 2, and then close the round manhole. Next, open the square manhole of cable box 1, connect the other end of connecting cable 2 to the line cable terminal 10, secure it with bolts, and then close the square manhole.

[0055] In one specific embodiment, the cable connection device further includes a current transformer core ring 7 and a transformer junction box 8, with the external wiring of the current transformer core ring 7 led to the transformer junction box 8. During installation, the transformer junction box 8 is opened, and the current ratio signal is introduced into the terminal box using a signal cable according to the terminal markings and the corresponding drawings.

[0056] Specifically, the current transformer core ring 7 is located inside the current transformer 6, and includes one measuring-stage transformer core ring and two protective-stage transformer core rings to measure the transformer load current and provide overload protection. The current transformer core ring 7 has both measurement and protection functions, and its current ratio is determined based on the transformer capacity and voltage. The primary and secondary current ratios of the current transformer core ring 7 are determined according to the transformer capacity and voltage, and are used for measuring load current and providing overload protection. The external wiring of the transformer core ring is led to the transformer junction box 8. The number of terminals in the junction box is determined according to the number of transformer core ring turns to facilitate the connection of external signal cables.

[0057] The current transformer 6 is installed below the cable box 1. Specifically, the current transformer 6 is installed at the bottom of the cable box 1 to reduce the installation height and save space.

[0058] In one specific embodiment, when the cable box 1 is sealed, oil is injected into the inside of the cable box 1. Specifically, the current transformer 6 is provided with a valve body for injecting or draining oil into the cable box 1. The valve body can be a ball valve 9, specifically a 25 ball valve, but other ball valve specifications can be selected as needed. The valve body is used for injecting or draining oil during the installation and disassembly of the cable box 1.

[0059] When using the cable connection device, first connect and install the cable box 1 and the current transformer 6 vertically, then install the cable box 1 sideways onto the side of the transformer housing 12, using a round flange for connection, and fix it with the lower bracket 11. Open the round manhole of the cable box 1, install the cable bracket 3, and place the connecting cable 2 with the insulation layer 15 inside the cable box 1. Install the connecting cable 2 on the cable bracket 3, connecting one end to the transformer winding lead cable 13. After connection, insulate the connector with the same thickness as the connecting cable 2, and close the round manhole. Open the square manhole, connect the other end of the connecting cable 2 to the line cable terminal 10, fix it with bolts, and close the square manhole. Vacuum fill the cable box 1 along with the transformer with oil. Install the grounding device 14. Open the transformer junction box 8, and according to the terminal markings and corresponding drawings, use a signal cable to introduce the current ratio signal into the terminal box.

[0060] This application provides a transformer, including a cable connection device, which is installed on the transformer housing 12. The cable connection device is any of the cable connection devices described above. The specific structure of the cable connection device has been described above; this application includes the aforementioned cable connection device and also achieves the above-mentioned technical effects.

[0061] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0062] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A cable connection device, characterized in that, The system includes a grounding device (14), a current transformer (6), a cable box (1), and a connecting cable (2) installed in the cable box (1). One end of the connecting cable (2) is connected to the transformer winding lead cable (13), and the other end is connected to the line cable terminal (10). The outside of the connecting cable (2) is wrapped with an insulation layer (15). The current transformer (6) is installed on the cable box (1). The grounding device (14) is used to ground the current transformer (6) and the cable box (1). The current transformer (6) is installed below the cable box (1). It also includes a current transformer core ring (7) and a transformer junction box (8). The external wiring of the current transformer core ring (7) is led to the transformer junction box (8). The transformer junction box (8) and the current transformer (6) are both located at the bottom of the outside of the cable box (1). It also includes a cable bracket (3) disposed inside the cable box (1). The cable bracket (3) is used to support the connecting cable (2). The cable bracket (3) includes a first hanger (3-1) fixedly connected to the cable box (1) and a second hanger (3-3) connected to the first hanger (3-1). The first hanger (3-1) is provided with a first cable mounting groove (3-2), and the second hanger (3-3) is provided with a second cable mounting groove (3-4). After the first hanger (3-1) and the second hanger (3-3) are fixed, the first cable mounting groove (3-2) and the second cable mounting groove (3-4) cooperate to form a hole structure for engaging the connecting cable (2). The first hanger (3-1) is installed on the top of the cable box (1) to realize the top suspension of the connecting cable (2). The current transformer (6) is equipped with a valve body for filling and draining oil into the cable box (1).

2. The cable connection device according to claim 1, characterized in that, It also includes a first sealing member and a second sealing member. The cable box (1) is provided with a first mounting hole (4) on the connecting cable (2) for connecting to the transformer winding lead cable (13) and a second mounting hole (5) on the connecting cable (2) for connecting to the line cable terminal (10). The first sealing member is used to open and close the first mounting hole (4), and the second sealing member is used to open and close the second mounting hole (5).

3. The cable connection device according to claim 2, characterized in that, The first mounting hole (4) and the second mounting hole (5) are hole structures of different shapes.

4. The cable connection device according to claim 1, characterized in that, The cable support (3) is made of laminated paperboard.

5. The cable connection device according to claim 1, characterized in that, When the cable box (1) is sealed, oil is injected into the inside of the cable box (1).

6. A transformer, comprising a cable connection device, characterized in that, The cable connection device is the cable connection device according to any one of claims 1-5.

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