Transformer bushing insulation on-line monitoring device

Abstract

The utility model discloses a transformer bushing insulation on-line monitoring device, which comprises a transformer bushing, an end screen adapter, an end screen leading-down device box and an IED host, the outer side of an end screen leading-out port of the transformer bushing is sleeved with the end screen adapter, and the end screen adapter and the IED host are both electrically connected with the end screen leading-down device box. The end screen adapter comprises an adapter body, an annular sliding groove, a threaded sleeve and a sealing sleeve, the annular sliding groove is formed in the outer side wall of the adapter body, the threaded sleeve is rotationally installed in the annular sliding groove, and external threads are arranged on the outer side of an end screen leading-out opening of the transformer bushing. Through the cooperation between the sealing sleeve and the sealing plug, the connection part of the connection cable and the transformer bushing end screen leading-out port joint is shielded and protected, and the sealing state of the connection part is ensured, thereby preventing external moisture from entering, causing short circuit or open circuit of an end screen adapter circuit, and affecting monitoring.

Description

Technical Field

[0001] This patent relates to the field of transformer bushing insulation condition monitoring technology, specifically to an online monitoring device for transformer bushing insulation. Background Technology

[0002] Bushings are key components of large transformers and reactors, and their proper operation is an important guarantee for power supply reliability. Online monitoring of transformer bushings, timely detection of bushing insulation defects and early warning are important means to ensure their safe operation. For capacitive transformer bushings, dielectric loss is an important indicator reflecting their insulation status. By monitoring the dielectric loss factor tanδ of the bushing online, the trend of equipment insulation status can be dynamically reflected.

[0003] In existing bushing online monitoring systems, bushing insulation signals are mainly derived from the end-screen adapter installed at the outlet of the high-voltage bushing end screen. However, the existing end-screen adapter has poor sealing performance. In rainy or snowy weather or in environments with high air humidity, external moisture will enter the traditional adapter, forming water accumulation or corroding the internal components of the traditional adapter, causing short circuits or open circuits in the traditional adapter circuit, thus affecting monitoring. Utility Model Content

[0004] The purpose of this patent is to provide an online monitoring device for transformer bushing insulation to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this patent provides the following technical solution: an online monitoring device for transformer bushing insulation, comprising a transformer bushing, a final screen adapter, a final screen lead-down device box, and an IED host. The final screen adapter is sleeved on the outside of the final screen lead-down outlet of the transformer bushing, and the final screen adapter and the IED host are electrically connected to the final screen lead-down device box.

[0006] The end-screen adapter includes an adapter body, an annular groove, a threaded sleeve, and a sealing sleeve. The outer side wall of the adapter body is provided with an annular groove, and the threaded sleeve is rotatably installed in the annular groove. The outer side of the end-screen outlet of the transformer bushing is provided with an external thread, and the threaded sleeve is installed on the outer side of the end-screen outlet of the transformer bushing by rotating the thread. A sealing sleeve is installed at the end of the adapter body.

[0007] An annular groove is provided on the outer side of the end screen outlet of the transformer bushing. A sealing plug is inserted into the inner cavity of the annular groove. A slot is provided on the side wall of the sealing plug. The slot has a trapezoidal cross-section. The sealing sleeve can be inserted into the slot.

[0008] Preferably, a positioning ring is installed on the outer side of the end screen outlet of the transformer bushing, and a sealing ring is fitted to the side wall of the positioning ring, which can fit against the side wall of the threaded sleeve.

[0009] Preferably, the adapter body is provided with a connecting cable, a dielectric loss sensor and a current sensor. The connecting cable is connected to the connector of the end screen outlet of the transformer bushing, and the dielectric loss sensor and the current sensor are both connected to the connecting cable.

[0010] Preferably, the end-screen lead-down device box is equipped with a zero-flux current transformer and a current monitoring circuit, both of which are connected to the IED host.

[0011] Preferably, the inner wall of the sealing sleeve is provided with a reinforcing rib, and the sidewall of the reinforcing rib is installed at the end of the adapter body.

[0012] Preferably, the end of the sealing sleeve furthest from the adapter body has an arc-shaped cross-section.

[0013] Compared with existing technologies, the beneficial effects of this patent are:

[0014] This device is equipped with a sealing sleeve in its end screen adapter. Through the cooperation between the sealing sleeve and the sealing plug, it can shield and protect the connection between the connecting cable and the transformer bushing end screen outlet joint, ensuring the sealing state of the connection and thus preventing external moisture from entering, which could cause a short circuit or open circuit in the end screen adapter circuit and affect monitoring.

[0015] In addition, the device is equipped with reinforcing ribs on the inner wall of the sealing sleeve to improve its strength and prevent deformation of the sealing sleeve, which could lead to sealing failure. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this patent.

[0017] Figure 2 This is a schematic diagram of the cross-sectional structure of the end-screen adapter of this patent.

[0018] Figure 3 This is a schematic diagram of the principle of this patent.

[0019] In the diagram: 1 Transformer bushing, 2 End screen adapter, 3 End screen lead-down device box, 4 IED main unit, 5 Annular groove, 6 Sealing plug, 7 Slot, 8 Positioning ring, 9 Sealing ring, 10 Connecting cable, 11 Dielectric loss sensor, 12 Current sensor, 13 Zero flux current transformer, 14 Current monitoring circuit, 15 Reinforcing rib, 21 Adapter body, 22 Annular groove, 23 Threaded sleeve, 24 Sealing sleeve. Detailed Implementation

[0020] The technical solutions of this patent embodiment will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this patent, and not all of them. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0021] Please see Figure 1-3 This patent provides a technical solution: an online monitoring device for transformer bushing insulation, including a transformer bushing 1, a final screen adapter 2, a final screen lead-down device box 3 and an IED host 4. The final screen adapter 2 is sleeved on the outside of the final screen lead-down outlet of the transformer bushing 1. The final screen adapter 2 and the IED host 4 are both electrically connected to the final screen lead-down device box 3.

[0022] The transformer bushing 1 and IED host 4 mentioned in this article are both existing technologies. The model of the IED host 4 is JC9000, but it is not limited to this model. The IED host 4 needs to be selected according to the power of the transformer.

[0023] The end screen current signal of the three-phase bushing is collected in the box of the end screen down device box 3. At the same time, the box is equipped with a zero flux current transformer 11 and a current monitoring circuit 12 with through-hole measurement method.

[0024] The dielectric loss sensor 11 and current sensor 12 in the end screen adapter 2, together with the zero flux current transformer 13 and current monitoring circuit 14 in the end screen lead-down device 3, realize the data acquisition of the end screen current. They can monitor the insulation status, dielectric loss factor, capacitance, leakage current, and bushing partial discharge characteristics, partial discharge quantity, and discharge number of the transformer bushing 1 in real time, and transmit them to the IED host 4.

[0025] The end-screen adapter 2 includes an adapter body 21, an annular groove 22, a threaded sleeve 23, and a sealing sleeve 24. The outer side wall of the adapter body 21 is provided with an annular groove 22. The threaded sleeve 23 is rotatably installed in the annular groove 22. The outer side of the end-screen outlet of the transformer bushing 1 is provided with an external thread. The threaded sleeve 23 is installed on the outer side of the end-screen outlet of the transformer bushing 1 by rotating the thread. The sealing sleeve 24 is installed at the end of the adapter body 21.

[0026] An annular groove 5 is provided on the outer side of the end screen outlet of the transformer bushing 1. A sealing plug 6 is inserted into the inner cavity of the annular groove 5. A slot 7 is provided on the side wall of the sealing plug 6. The cross section of the slot 7 is trapezoidal. The sealing sleeve 24 can be inserted into the slot 7.

[0027] To ensure the sealing of the connection between the connecting cable 10 and the outlet joint of the transformer bushing 1, this device uses a sealing sleeve 24 and a sealing plug 6. After the outlet adapter 2 is connected to the outlet joint of the transformer bushing 1, the sealing sleeve 24 will be continuously inserted into the slot 7 of the sealing plug 6 as the threaded sleeve 23 is continuously tightened, thus ensuring the sealing effect of the connection and preventing the entry of external moisture.

[0028] Specifically, a positioning ring 8 is installed on the outer side of the end screen outlet of the transformer bushing 1, and a sealing ring 9 is fitted to the side wall of the positioning ring 8. The sealing ring 9 can fit against the side wall of the threaded sleeve 23.

[0029] Specifically, the adapter body 21 is equipped with a connecting cable 10, a dielectric loss sensor 11 and a current sensor 12. The connecting cable 10 is connected to the connector of the end screen outlet of the transformer bushing 1, and both the dielectric loss sensor 11 and the current sensor 12 are connected to the connecting cable 10.

[0030] Specifically, the end screen lead-down device box 3 is equipped with a zero flux current transformer 13 and a current monitoring circuit 14, both of which are connected to the IED host 4.

[0031] The IED host 4 proposed in this paper can monitor the insulation characteristic parameters of the transformer bushing 1 locally, and display the measurement results locally through calculation and processing, and transmit them digitally to the back-end server of the substation via the communication bus.

[0032] Specifically, a reinforcing rib 15 is installed on the inner wall of the sealing sleeve 24, and the side wall of the reinforcing rib 15 is installed at the end of the adapter body 21.

[0033] The reinforcing rib 15 can increase the strength of the sealing sleeve 24, prevent it from deforming, and ensure the tightness of the connection between it and the sealing plug 6.

[0034] Specifically, the end of the sealing sleeve 24 away from the adapter body 21 has an arc-shaped cross section;

[0035] By setting the end of the sealing sleeve 24 to be arc-shaped, the sealing sleeve 24 can be prevented from scratching the inner wall of the slot 7 when it is inserted into the sealing plug 6 slot 7, thus avoiding affecting the sealing performance of the connection between the two.

[0036] Working principle: The end screen adapter 2 is sleeved on the outside of the end screen outlet joint of the transformer bushing 1. Then, the end screen adapter 2 is fixed by the engagement between the threaded sleeve 23 and the thread on the outside of the end screen outlet of the transformer bushing 1. During this process, the sealing sleeve 24 will be continuously inserted into the slot 7 of the sealing plug 6 to ensure the sealing effect of the connection and prevent the entry of external moisture.

[0037] After the connection is completed, the dielectric loss sensor 11 and current sensor 12 in the end screen adapter 2, the zero flux current transformer 13 and current monitoring circuit 14 in the end screen lead-down device 3, realize the data acquisition of the end screen current, and can monitor the insulation status, dielectric loss factor, capacitance, leakage current and bushing partial discharge characteristics, partial discharge quantity, discharge number, etc. of the transformer bushing 1 in real time, and transmit them to the IED host 4.

[0038] The IED host 4 can monitor the insulation characteristic parameters of the transformer bushing 1 locally, and display the measurement results locally through calculation and processing, and transmit them digitally to the back-end server of the substation via the communication bus.

[0039] It will be apparent to those skilled in the art that this patent is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this patent. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this patent is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this patent. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0040] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A transformer bushing insulation online monitoring device, comprising a transformer bushing (1), a terminal screen adapter (2), a terminal screen lead-down device box (3), and an IED host (4), characterized in that: The outer side of the end screen outlet of the transformer bushing (1) is fitted with an end screen adapter (2), and the end screen adapter (2) and the IED host (4) are electrically connected to the end screen lead-down device box (3). The end-screen adapter (2) includes an adapter body (21), an annular groove (22), a threaded sleeve (23), and a sealing sleeve (24). The outer side wall of the adapter body (21) is provided with an annular groove (22). The threaded sleeve (23) is rotatably installed in the annular groove (22). The outer side of the end-screen outlet of the transformer bushing (1) is provided with an external thread. The threaded sleeve (23) is installed on the outer side of the end-screen outlet of the transformer bushing (1) by rotating the thread. The sealing sleeve (24) is installed at the end of the adapter body (21). An annular groove (5) is provided on the outer side of the end screen outlet of the transformer bushing (1). A sealing plug (6) is inserted into the inner cavity of the annular groove (5). A slot (7) is provided on the side wall of the sealing plug (6). The cross section of the slot (7) is trapezoidal. The sealing sleeve (24) can be inserted into the slot (7).

2. The online monitoring device for transformer bushing insulation according to claim 1, characterized in that: A positioning ring (8) is installed on the outer side of the end screen outlet of the transformer bushing (1), and a sealing ring (9) is fitted to the side wall of the positioning ring (8), which can fit against the side wall of the threaded sleeve (23).

3. The online monitoring device for transformer bushing insulation according to claim 1, characterized in that: The adapter body (21) is provided with a connecting cable (10), a dielectric loss sensor (11) and a current sensor (12). The connecting cable (10) is connected to the connector of the end screen outlet of the transformer bushing (1). The dielectric loss sensor (11) and the current sensor (12) are both connected to the connecting cable (10).

4. The online monitoring device for transformer bushing insulation according to claim 1, characterized in that: The end screen lead-down device box (3) is equipped with a zero flux current transformer (13) and a current monitoring circuit (14), both of which are connected to the IED host (4).

5. The online monitoring device for transformer bushing insulation according to claim 1, characterized in that: The inner wall of the sealing sleeve (24) is fitted with a reinforcing rib (15), and the side wall of the reinforcing rib (15) is installed at the end of the adapter body (21).

6. The online monitoring device for transformer bushing insulation according to claim 5, characterized in that: The end of the sealing sleeve (24) away from the adapter body (21) has an arc-shaped cross section.

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