A safe and efficient nitrogen-filled oil-rolling system and method for oil-immersed current transformers

Abstract

The present invention provides a safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformers, comprising an oil-immersed current transformer, an oil sampling valve disposed on the oil-immersed current transformer, a four-way valve, a nitrogen cylinder, and a pressure-reducing valve disposed on the nitrogen cylinder; the four-way valve has a first quick-connect port, a second quick-connect port, a third quick-connect port, and a fourth quick-connect port; the pressure-reducing valve is connected to the first quick-connect port via a pipeline, and the oil sampling valve is connected to the third quick-connect port via a pipeline; when the four-way valve is closed, the first quick-connect port is connected to the fourth quick-connect port, and the third quick-connect port is connected to the second quick-connect port; when the four-way valve is open, the first quick-connect port is connected to the third quick-connect port, and the second quick-connect port is connected to the fourth quick-connect port. The present invention prevents a hose from being detached from the charging port due to air pressure by switching between the two states of the four-way valve; and the coordinated use of the valve and the four-way valve effectively prevents oil from flowing through the hose to the pressure-reducing valve, contaminating or even damaging the pressure-reducing valve.

Description

Technical Field

[0001] The present invention relates to the technical field of oil-immersed current transformers, and more particularly to a safe and efficient nitrogen-filling and oil-rolling system for oil-immersed current transformers and a nitrogen-filling and oil-rolling method thereof. Background Art

[0002] During substation maintenance, nitrogen flushing or tumbling is a common procedure when treating oil-immersed equipment. For example, when treating an oil-immersed current transformer with excessive hydrogen levels, we perform a vacuum dehydrogenation process. The process is as follows: data recording, oil draining from the expander, vacuum pumping, nitrogen tumbling, and multiple vacuum pumping and nitrogen tumbling cycles. Finally, oil replenishment and quiescence are performed before testing. The nitrogen tumbling process ensures that the transformer oil is thoroughly tumbled and stirred, ensuring a more effective vacuum pumping cycle.

[0003] In the past, during the nitrogen filling process, the nitrogen bottle was connected to the oil sampling valve of the oil-immersed current transformer through a pressure reducing valve and a hose. After unscrewing the oil sampling valve, the pressure reducing valve was opened to make the nitrogen output pressure about 0.2-0.05MPa to roll the transformer oil inside the transformer. The rolling was continued for 15 minutes. This method of nitrogen filling and oil rolling has the following shortcomings:

[0004] 1) After opening the oil sampling valve, the oil in the oil-immersed current transformer will flow back into the hose. Immediately open the pressure reducing valve connected to the nitrogen cylinder and use the nitrogen pressure to fill the oil in the hose back into the current transformer. Maintain this pressure for 15 minutes to ensure that the nitrogen fully stirs the oil inside the current transformer. However, if the pressure reducing valve of the nitrogen cylinder is not opened in time after opening the oil sampling valve, oil will flow through the hose into the pressure reducing valve, contaminating or even damaging the pressure reducing valve.

[0005] 2) If you open the nitrogen bottle and the pressure reducing valve first and then the oil sampling valve, the hose will be quickly filled with nitrogen and the hose will be separated from the inflation port due to pressure;

[0006] 3) When the oil sampling valve is opened, the hose will have a certain rebound force as the valve rotates, and may even become tangled, causing the valve to rotate in the opposite direction due to the elastic force of the hose and possibly close the valve. At the same time, if the hose is not firmly connected to the oil sampling port, there is a possibility that the two will separate due to the rebound force. Summary of the Invention

[0007] The present invention is designed to overcome the following problems existing in the above-mentioned prior art: when the oil sampling valve is opened, if the pressure reducing valve of the nitrogen bottle is not opened in time, oil will flow into the pressure reducing valve through the hose, contaminating or even damaging the pressure reducing valve; if the nitrogen bottle and the pressure reducing valve are opened first and then the oil sampling valve is opened, the hose will be quickly filled with nitrogen, causing the hose to be separated from the inflation port under pressure; when the oil sampling valve is opened, the hose will have a certain rebound force as the oil sampling valve rotates, and may even roll up, causing the valve to rotate in the opposite direction due to the elastic force of the hose, resulting in the possibility of the valve being closed; at the same time, if the hose is not firmly connected to the oil sampling port, there is a possibility that the two will be separated due to the rebound force.

[0008] The technical solution adopted by the present invention is to provide a safe and efficient nitrogen-filled and oil-rolled system for an oil-immersed current transformer, comprising an oil-immersed current transformer, an oil sampling valve provided on the oil-immersed current transformer, a four-way valve, a nitrogen cylinder, and a pressure reducing valve provided on the nitrogen cylinder; the four-way valve has a first quick-connect port, a second quick-connect port, a third quick-connect port, and a fourth quick-connect port; the pressure reducing valve is connected to the first quick-connect port via a pipeline, and the oil sampling valve is connected to the third quick-connect port via a pipeline; when the four-way valve is in a closed state, the first quick-connect port is connected to the fourth quick-connect port, and the third quick-connect port is connected to the second quick-connect port; when the four-way valve is in an open state, the first quick-connect port is connected to the third quick-connect port, and the second quick-connect port is connected to the fourth quick-connect port.

[0009] The present invention can prevent the hose from being separated from the inflation port due to air pressure by switching between the two states of the four-way valve; and the coordinated use of the valve and the four-way valve can effectively prevent oil from flowing through the hose to the pressure reducing valve, thereby contaminating or even damaging the pressure reducing valve.

[0010] Preferably, the second quick connector is connected to a conduit, and the end of the conduit extends into a container.

[0011] Preferably, a valve is provided in the pipeline between the oil sampling valve and the four-way valve. The oil sampling valve is connected to the valve in the closed state via a short hose (the other end of the valve is temporarily disconnected from the hose). The oil sampling valve can then be opened or closed at will, thereby preventing the pipeline from generating a certain rebound force as the oil sampling valve rotates, or even from curling up, which could cause the oil sampling valve to rotate in the opposite direction due to the elastic force of the pipeline and cause the oil sampling valve to close.

[0012] Preferably, the valve is provided with a fifth quick socket and a sixth quick socket.

[0013] Preferably, the fifth quick connector is connected to the oil sampling valve through a pipeline.

[0014] Preferably, the sixth quick socket is connected to the third quick socket through a pipeline.

[0015] Preferably, the pressure reducing valve is provided with a seventh quick socket, and the seventh quick socket is connected to the first quick socket through a pipeline.

[0016] Preferably, the container is an oil drum, and the conduit is a hose.

[0017] Preferably, the pipe is a hose.

[0018] The present invention also provides a safe and efficient nitrogen filling and oil rolling method for an oil-immersed current transformer nitrogen filling and oil rolling system as described above, comprising the following steps:

[0019] S1: Connect the nitrogen bottle to the first quick-connect port of the four-way valve through a pressure reducing valve and a pipe. The second quick-connect port of the four-way valve is connected to the container through a conduit. Connect the oil sampling valve of the oil-immersed current transformer to the valve through a pipe. At this time, do not connect the valve to the third quick-connect port of the four-way valve.

[0020] S2: When the connection method of relevant components is checked as described above, open the oil sampling valve. At this time, since the oil sampling valve is only connected to the valve through a short pipe, the valve can rotate as the oil sampling valve rotates and opens, and the valve is in a closed state, which can effectively prevent the oil in the current transformer from flowing out; at the same time, it can solve the problem that "when the oil sampling valve is opened, the hose will have a certain rebound force as the oil sampling valve rotates, and may even roll up, causing the valve to rotate in the opposite direction due to the elastic force of the hose, resulting in the possibility of the valve closing. At the same time, if the hose is not firmly connected to the oil sampling port, there is a possibility that the two will separate due to the rebound force."

[0021] S3: At this time, connect the valve to the third quick connector of the four-way valve through the pipeline.

[0022] S4: Check that the four-way valve is closed, then open the nitrogen bottle main switch and the pressure reducing valve in sequence. The nitrogen in the nitrogen bottle now flows into the atmosphere through the fourth quick-connect port of the four-way valve, preventing the hose from being separated from the inflation port due to air pressure. At this point, open the valve again, and the oil in the oil-immersed current transformer flows into the container from the second quick-connect port of the four-way valve. This avoids the problem of "when the oil sampling valve is opened, if the pressure reducing valve of the nitrogen bottle is not opened in time, the oil will flow through the hose to the pressure reducing valve, contaminating or even damaging the pressure reducing valve."

[0023] S5: Then the four-way valve is switched to the open state. At this time, the first quick-connect port and the third quick-connect port of the four-way valve are connected. Then, the nitrogen in the nitrogen bottle is fed into the oil chamber of the oil-immersed current transformer through the first quick-connect port and the third quick-connect port of the four-way valve to complete the nitrogen filling and oil rolling process.

[0024] S6: When the oil boiling is finished, switch the four-way valve to the closed state. At this time, the nitrogen flows to the atmosphere and the oil flows into the container. Then close the valve, the main switch of the nitrogen bottle and the pressure reducing valve in turn, and then remove the pipe between the valve and the four-way valve, close the oil sampling port, and then disassemble all the pipes to complete the disassembly work.

[0025] Compared with the prior art, the beneficial effects are:

[0026] The present invention can prevent the hose from being separated from the inflation port due to air pressure by switching between the two states of the four-way valve; the coordinated use of the valve and the four-way valve can effectively prevent oil from flowing through the hose to the pressure reducing valve, thereby contaminating or even damaging the pressure reducing valve; the oil sampling valve is connected to the valve in the closed state via a short hose (the other end of the valve is temporarily not connected to the hose), and the oil sampling valve can be opened or closed at will at this time, which can prevent the hose from having a certain rebound force as the oil sampling valve rotates, or even rolling up, causing the valve to rotate in the opposite direction due to the elastic force of the hose and thus closing the valve; at the same time, if the hose is not firmly connected to the oil sampling port, there is a possibility that the two will be separated due to the rebound force. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the nitrogen-filled oil-rolling system of the oil-immersed current transformer of the present invention. DETAILED DESCRIPTION

[0028] The drawings are for illustrative purposes only and should not be construed as limiting this patent. To better illustrate the embodiments, some components in the drawings may be omitted, enlarged, or reduced in size, and do not represent actual product dimensions. Those skilled in the art will understand that some well-known structures and their descriptions may be omitted from the drawings. The positional relationships depicted in the drawings are for illustrative purposes only and should not be construed as limiting this patent.

[0029] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", "long", "short", etc. indicating the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0030] The technical solution of the present invention is further described in detail below through specific embodiments and in conjunction with the accompanying drawings:

[0031] Example 1

[0032] like Figure 1 As shown, a safe and efficient nitrogen-filled and oil-rolling system for an oil-immersed current transformer includes an oil-immersed current transformer 1, an oil sampling valve 2 provided on the oil-immersed current transformer 1, a four-way valve 7, a nitrogen cylinder 5, and a pressure reducing valve 4 provided on the nitrogen cylinder 5. The four-way valve 7 has a first quick-connect port 71, a second quick-connect port 72, a third quick-connect port 73, and a fourth quick-connect port 74. The pressure reducing valve 4 is connected to the first quick-connect port 71 via a pipeline, and the oil sampling valve 2 is connected to the third quick-connect port 73 via a pipeline. When the four-way valve 7 is in a closed state, the first quick-connect port 71 is connected to the fourth quick-connect port 74, and the third quick-connect port 73 is connected to the second quick-connect port 72. When the four-way valve 7 is in an open state, the first quick-connect port 71 is connected to the third quick-connect port 73, and the second quick-connect port 72 is connected to the fourth quick-connect port 74.

[0033] The second quick connector 72 is connected to a conduit 9 , and the end of the conduit 9 extends into a container 8 .

[0034] In addition, a valve 6 is provided in the pipe 3 between the oil sampling valve 2 and the four-way valve 7. The oil sampling valve 2 is connected to the closed valve 6 via a short pipe 3 (the other end of the valve 6 is temporarily disconnected from the pipe 3). At this time, the oil sampling valve 2 can be opened or closed at will, thereby preventing the pipe 3 from generating a certain rebound force as the oil sampling valve 2 rotates, or even from curling up, which could cause the oil sampling valve 2 to rotate in the opposite direction due to the elastic force of the pipe 3 and cause the oil sampling valve 2 to close.

[0035] The valve 6 is provided with a fifth quick-connection 61 and a sixth quick-connection 62 .

[0036] In addition, the fifth quick connector 61 is connected to the oil sampling valve 2 through the pipeline 3 .

[0037] The sixth quick-connect port 62 is connected to the third quick-connect port 73 through the pipe 3 .

[0038] In addition, a seventh quick-connect port 41 is provided on the pressure reducing valve 4 , and the seventh quick-connect port 41 is connected to the first quick-connect port 71 through the pipeline 3 .

[0039] The container 8 is an oil drum, and the conduit 9 is a hose.

[0040] In addition, the pipe 3 is a hose.

[0041] Example 2

[0042] A safe and efficient nitrogen filling and oil rolling method for a nitrogen filling and oil rolling system of an oil-immersed current transformer comprises the following steps:

[0043] S1: Connect the nitrogen bottle 5 through the pressure reducing valve 4 and then through the pipe to the first quick-connect port 71 of the four-way valve 7. The second quick-connect port 72 of the four-way valve 7 is connected to the container 8 through a conduit. The oil sampling valve 2 of the oil-immersed current transformer 1 is connected to the valve 6 through the pipe 3. At this time, the valve 6 and the third quick-connect port 73 of the four-way valve 7 are not connected.

[0044] S2: When checking that the connection method of relevant components is as above, open the oil sampling valve 2. At this time, since the oil sampling valve 2 is only connected to the valve 6 through the short pipe 3, the valve 6 can rotate as the oil sampling valve 2 rotates and opens, and the valve 6 is in a closed state, which can effectively prevent the oil in the current transformer from flowing out; at the same time, it can solve the problem that "when the oil sampling valve is opened, the hose will have a certain rebound force as the oil sampling valve rotates, and may even roll up, causing the valve to rotate in the opposite direction due to the elastic force of the hose, resulting in the possibility of the valve closing. At the same time, if the hose is not firmly connected to the oil sampling port, there is a possibility that the two will separate due to the rebound force."

[0045] S3: At this time, the valve 6 is connected to the third quick-connect port 73 of the four-way valve 7 through the pipeline 3.

[0046] S4: Check that the four-way valve 7 is in the closed state, then open the main switch of the nitrogen bottle 5 and the pressure reducing valve 4 in sequence. At this time, the nitrogen in the nitrogen bottle 5 flows into the atmosphere through the fourth quick-connect port 74 of the four-way valve 7, which can prevent the hose from being separated from the inflation port due to air pressure. At this time, open the valve 6 again, and the oil in the oil-immersed current transformer 1 flows from the second quick-connect port 72 of the four-way valve 7 to the container 8, which can avoid the problem of "when opening the oil sampling valve 2, if the pressure reducing valve 4 of the nitrogen bottle 5 is not opened in time, the oil will flow into the pressure reducing valve 4 through the pipeline, contaminating or even damaging the pressure reducing valve 4."

[0047] S5: Then the four-way valve 7 is switched to the open state. At this time, the first quick-connect port 71 and the third quick-connect port 73 of the four-way valve 7 are connected. Then, the nitrogen in the nitrogen bottle 5 is fed into the oil chamber of the oil-immersed current transformer 1 through the first quick-connect port 71 and the third quick-connect port 73 of the four-way valve 7 to complete the nitrogen filling and oil rolling process.

[0048] S6: When the oil boiling is finished, switch the four-way valve 7 to the closed state. At this time, the nitrogen flows to the atmosphere and the oil flows into the container 8. Then close the valve 6, the main switch of the nitrogen bottle 5 and the pressure reducing valve 4 in sequence, and then remove the pipe 3 between the valve 6 and the four-way valve 7, close the oil sampling port 2, and then disassemble all the pipes 3 to complete the disassembly work.

[0049] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A safe and efficient nitrogen filling and oil rolling system for oil-immersed current transformers, characterized by: The invention comprises an oil-immersed current transformer (1), an oil sampling valve (2) provided on the oil-immersed current transformer (1), a four-way valve (7), a nitrogen bottle (5), and a pressure reducing valve (4) provided on the nitrogen bottle (5); the four-way valve (7) has a first quick socket (71), a second quick socket (72), a third quick socket (73), and a fourth quick socket (74); the pressure reducing valve (4) is connected to the first quick socket (71) through a pipeline (3), the oil sampling valve (2) is connected to the third quick socket (73) through a pipeline (3), and the pressure reducing valve (4) is connected to the four-way valve (7). When the valve (7) is in a closed state, the first quick socket (71) is in communication with the fourth quick socket (74), and the third quick socket (73) is in communication with the second quick socket (72); when the four-way valve (7) is in an open state, the first quick socket (71) is in communication with the third quick socket (73), and the second quick socket (72) is in communication with the fourth quick socket (74); the second quick socket (72) is connected to a conduit (9), the end of which extends into a container (8); and the fourth quick socket (74) is in communication with the atmosphere.

2. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to claim 1, characterized in that: A valve (6) is provided in the pipeline (3) between the oil sampling valve (2) and the four-way valve (7).

3. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to claim 2, characterized in that: The valve (6) is provided with a fifth quick-connection (61) and a sixth quick-connection (62).

4. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to claim 3, characterized in that: The fifth quick-connect port (61) is connected to the oil sampling valve (2) via a pipeline (3).

5. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to claim 4, characterized in that: The sixth quick-connect port (62) is connected to the third quick-connect port (73) through a pipe (3).

6. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to claim 1, characterized in that: The pressure reducing valve (4) is provided with a seventh quick-connection (41), and the seventh quick-connection (41) is connected to the first quick-connection (71) through a pipeline (3).

7. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to claim 1, characterized in that: The container (8) is an oil drum, and the conduit (9) is a hose.

8. A safe and efficient nitrogen-filled oil-rolling system for oil-immersed current transformer according to any one of claims 1 to 7, characterized in that: The pipeline (3) is a hose.

9. A method for nitrogen filling and oil rolling of a safe and efficient nitrogen filling and oil rolling system for an oil-immersed current transformer according to any one of claims 2 to 5, characterized in that: The following steps are involved: S1: Connect the nitrogen bottle (5) through the pressure reducing valve (4) and then to the first quick-connect port (71) of the four-way valve (7) through a pipe, and the second quick-connect port (72) of the four-way valve (7) is connected to the container (8) through a conduit; the oil sampling valve (2) of the oil-immersed current transformer (1) is connected to the valve (6) through the pipe (3), and the valve (6) and the third quick-connect port (73) of the four-way valve (7) are temporarily not connected; S2: When the connection mode of the relevant components is checked as described above, open the oil sampling valve (2). At this time, since the oil sampling valve (2) is only connected to the valve (6) through the short pipe (3), the valve (6) can rotate along with the rotation of the oil sampling valve (2). The valve (6) is in the closed state, which can effectively prevent the oil in the current transformer from flowing out. S3: At this time, the valve (6) is connected to the third quick-connect port (73) of the four-way valve (7) through the pipeline (3); S4: Check that the four-way valve (7) is in the closed state, then open the main switch of the nitrogen bottle (5) and the pressure reducing valve (4) in sequence, at which time the nitrogen in the nitrogen bottle (5) flows into the atmosphere through the fourth quick-connect port (74) of the four-way valve (7); at this time, open the valve (6) again, and the oil in the oil-immersed current transformer (1) flows into the container (8) through the second quick-connect port (72) of the four-way valve (7); S5: Then the four-way valve (7) is switched to the open state. At this time, the first quick-connect port (71) and the third quick-connect port (73) of the four-way valve (7) are connected, and the nitrogen in the nitrogen bottle (5) is filled into the oil chamber of the oil-immersed current transformer (1) through the first quick-connect port (71) and the third quick-connect port (73) of the four-way valve (7), thereby completing the nitrogen filling and oil rolling process; S6: When the oil is boiled, switch the four-way valve (7) to the closed state. At this time, the nitrogen flows to the atmosphere and the oil flows to the container (8). Then, close the valve (6), the main switch of the nitrogen bottle (5) and the pressure reducing valve (4) in sequence. Then remove the pipe (3) between the valve (6) and the four-way valve (7), close the oil sampling valve (2), and then disassemble all the pipes (3) to complete the disassembly work.

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