Transformer system and maintenance method thereof

Abstract

The invention relates to the technical field of transformers, and discloses a transformer system which comprises a transformer, an oil conservator, a breathing tube, a respirator and a monitoring assembly. The pressure and the humidity in the oil conservator communicated with the valve body are measured through the pressure gauge and the humidity in the monitoring assembly, and therefore whether abnormal work such as blockage exists in the respirator or not can be visually judged according to the difference value between the reading of the pressure gauge and the atmospheric pressure. Whether the conservator is communicated with the external atmosphere or not can be judged only according to the breathing phenomenon, and the safety of a transformer system is improved; the invention further discloses a maintenance method of the transformer system, whether the respirator is maintained after the heavy gas protection loop is cut off or not is determined according to the difference value between the pressure in the oil conservator and the atmospheric pressure, and the problems that the labor and management cost is increased and the safety of the transformer system is reduced due to the fact that the heavy gas protection loop is directly stopped are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of transformers, and in particular to a transformer system and a maintenance method thereof. Background Art

[0002] The oil pillow is an oil storage device for transformers. The oil pillow can adjust the oil level inside the transformer. The principle is that when the transformer increases due to load, the oil temperature rises, and the oil in the oil tank expands, the excess oil will flow into the oil pillow. On the contrary, when the temperature drops, the oil in the oil pillow will flow back to the transformer tank, thereby automatically adjusting the oil level, thereby ensuring that the transformer tank is full of oil. The oil pillow of a large transformer is usually equipped with an oil-resistant nylon rubber diaphragm bag (hereinafter referred to as a capsule). The inside of the capsule is connected to the atmosphere through a breathing tube and a respirator in turn, and the outside of the capsule is in contact with the insulating oil. When the oil temperature in the transformer tank rises and expands, the oil level in the oil pillow also rises, and the capsule exhausts air to the outside; on the contrary, when the oil level in the oil pillow drops, the capsule inhales air from the outside, automatically balancing the pressure inside and outside the bag.

[0003] Therefore, the respirator is also an important auxiliary component of the transformer. Its main function is not only to connect the transformer oil pillow capsule with the outside atmosphere, but also to absorb the air impurities and water vapor entering the transformer oil pillow capsule through the silica gel inside it, so as to keep the air inside the oil pillow capsule dry. The color-changing silica gel in the respirator is blue in a dry state, and turns red or pink after absorbing a certain amount of water. When the total amount of silica gel discoloration reaches 2 / 3, the substation operation and maintenance personnel need to replace the silica gel in the respirator.

[0004] The patency of the breather will directly affect whether the transformer oil pillow capsule is connected to the outside atmosphere, and thus affect the normal operation of the transformer. At present, whether the transformer oil pillow capsule is connected to the outside atmosphere is generally judged by whether there is a breathing phenomenon (oil bubbling) in the breather; but when the temperature difference does not change much or the transformer load does not change much, the oil temperature inside the transformer does not change much, and the volume change caused by the thermal expansion and contraction of the oil is not large, and the breather often has no obvious breathing phenomenon. At this time, it is impossible to intuitively judge whether the breather is blocked, and it is also impossible to judge whether the pressure inside the oil pillow is balanced with the atmospheric pressure. If the breather is actually blocked, the internal pressure of the transformer may increase, causing the transformer pressure to release and other non-electrical quantity protection actions, or due to the negative pressure inside, air may be sucked into the transformer oil leakage point, causing the transformer to light gas action and other abnormalities.

[0005] In addition, when replacing the transformer breather silicone, it is impossible to determine whether the breather is directly connected to the atmosphere, and thus it is impossible to judge the pressure inside the oil pillow capsule. In order to prevent a large pressure difference between the pressure inside the oil pillow capsule and the atmospheric pressure, when performing breather maintenance, the gas relay malfunctions and cuts off the running transformer. Certain approval procedures need to be performed to withdraw the corresponding transformer gas protection, which greatly increases manpower and management costs. At the same time, disabling the heavy gas protection of the equipment when replacing the breather silicone brings certain risks to the safe operation of the transformer. If a minor inter-turn short circuit fault occurs inside the equipment during the replacement process, the heavy gas protection cannot play its due role, resulting in the transformer not being able to be cut off from the power grid in time, and the fault further develops into serious accidents such as transformer explosion. Summary of the invention

[0006] The purpose of the present invention is to provide a transformer system and a maintenance method thereof, so as to solve the problem that in the existing transformer system, it is only possible to judge whether the transformer oil pillow capsule is connected to the outside atmosphere based on the breathing phenomenon in the breather, but it is impossible to intuitively judge whether the breather is blocked, whether there is leakage in the connecting pipe between the oil pillow and the breather, and whether the pressure in the oil pillow is balanced with the atmospheric pressure.

[0007] In order to achieve the above object, the present invention provides a transformer system, which includes a transformer, an oil pillow, a breathing tube, a respirator and a monitoring component;

[0008] A heavy gas protection circuit is provided in the transformer;

[0009] The oil pillow is connected to the transformer, the breathing tube is connected to the oil pillow and the breathing apparatus, and the monitoring component is connected to the breathing apparatus;

[0010] The monitoring assembly includes a valve body, a pressure gauge and a humidity gauge;

[0011] The valve body has a first interface, a second interface, a third interface and a fourth interface. The first interface is connected to the breathing tube and connected to the oil pillow. The second interface is connected to the respirator. The pressure gauge is installed at the third interface, and the humidity gauge is installed at the fourth interface.

[0012] Furthermore, at least two annular sealing rings are provided between the connecting end surfaces of the first interface and the breathing tube, and between the connecting end surfaces of the second interface and the respirator.

[0013] Furthermore, a quick connector is connected between the pressure gauge and the third interface, and between the humidity gauge and the fourth interface;

[0014] The quick connector includes a female connector, a male connector and a snap-on component. The female connector is welded to the valve body, and the male connector is screwed to the pressure gauge or the humidity gauge respectively. The snap-on component can detachably lock the male connector and the female connector, and the snap-on component is located at the outer periphery of the male connector and the female connector. The end faces of the male connector and the female connector are sealed and connected.

[0015] Furthermore, the pressure gauge and the humidity gauge are both provided with a data transmission module;

[0016] The data transmission module is used to transmit the reading of the pressure gauge or the humidity gauge.

[0017] Furthermore, a light gas protection circuit is also provided in the transformer.

[0018] Furthermore, it also includes an anti-mistaken cut-off circuit, which includes a first normally open contact and a relay;

[0019] The first normally open contact is electrically connected to the pressure gauge, the light gas protection circuit includes a first normally closed contact, and the first normally closed contact is electrically connected to the relay;

[0020] When the pressure measured by the pressure gauge reaches a preset value, the first normally open contact is closed, the relay is energized, the first normally closed contact is disconnected, and the light gas protection circuit is disconnected.

[0021] Furthermore, it also includes an oil pillow negative pressure warning circuit;

[0022] The oil pillow negative pressure warning circuit includes a second normally open contact, which is electrically connected to the relay. When the relay is energized, the second normally open contact is closed, and the oil pillow negative pressure warning circuit is connected.

[0023] The present invention also provides a maintenance method for the above transformer system, which comprises the following steps:

[0024] S1, read the pressure value measured by the pressure gauge, and compare the difference between the reading and the atmospheric pressure with a predetermined value. If the difference is less than the predetermined value, step S2;

[0025] If the difference is greater than a predetermined value, the heavy gas protection circuit in the transformer is first disabled, and then step S2 is performed;

[0026] S2. Replace the silica gel in the respirator;

[0027] S3. Depending on whether the heavy gas protection circuit is disabled in step S2, if the heavy gas protection circuit is disabled in step S2, re-enable it.

[0028] Furthermore, before step S1, the method further includes the following steps:

[0029] S11, observe the color of the silica gel in the respirator, and if the total amount of color change exceeds the set threshold, execute step S1.

[0030] Compared with the prior art, the transformer system and maintenance method provided by the present invention have the following beneficial effects:

[0031] The present invention provides a transformer system, which includes a transformer, an oil pillow, a breathing tube, a respirator and a monitoring component. The oil pillow and the respirator are connected through the breathing tube. By connecting the monitoring component to the breathing tube, the pressure gauge and the hygrometer connected to the valve body can measure the pressure and humidity in the breathing tube. Since the breathing tube is arranged in the oil pillow and the respirator, no matter whether the respirator works normally or not, the pressure gauge and the hygrometer can obtain the pressure and humidity of the oil pillow connected to the breathing tube by measuring the pressure and humidity in the breathing tube, and can judge whether the respirator has abnormal abnormality such as blockage according to the difference between the pressure value and the atmospheric pressure, and can judge whether the moisture absorption function of the respirator is normally exerted and whether there are leakage points between the top of the respirator and the transformer oil pillow according to the humidity value, thereby avoiding the problem that the oil pillow can only be judged whether it is connected to the outside atmosphere according to the breathing phenomenon, but cannot intuitively judge whether the respirator is blocked, whether there is leakage in the connecting pipe between the oil pillow and the respirator, and whether the pressure in the oil pillow is balanced with the atmospheric pressure; thereby improving the safety of the transformer system.

[0032] The present invention also provides a maintenance method for the above-mentioned transformer system. When the transformer system in the prior art is performing replacement and maintenance of the breather silicone, in order to prevent the heavy gas protection circuit from mistakenly cutting off the transformer power supply due to a large difference between the pressure in the oil pillow and the atmospheric pressure, it is usually necessary to withdraw the heavy gas protection circuit; and the above-mentioned transformer system provided by the present invention can measure the pressure in the oil pillow. Therefore, when performing maintenance, this maintenance method compares the difference between the pressure value measured by the pressure gauge and the atmospheric pressure with a predetermined value. If the difference is less than the predetermined value, it means that the pressure in the oil pillow is similar to or the same as the atmospheric pressure, and there will be no The heavy gas protection circuit is triggered to cut off the transformer without deactivating the heavy gas protection circuit to ensure the safety of the entire power grid during the maintenance of the breather silicone replacement; if the difference is greater than the preset value, it means that the pressure in the oil pillow and the atmospheric pressure have a large difference, and there is a breather blockage or other abnormalities in the transformer system, then the heavy gas protection circuit will be exited first to prevent the heavy gas protection circuit from directly cutting off the transformer power supply during the maintenance process; thus, the difference between the pressure gauge reading and the atmospheric pressure is used to determine whether to exit the heavy gas protection circuit, avoiding direct exit from the heavy gas protection circuit, saving corresponding manpower and management costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a connection diagram of a transformer system according to an embodiment of the present invention;

[0034] Figure 2 is a schematic structural diagram of a monitoring component in a transformer system according to an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of electrical connections of an anti-miscutoff circuit, a light gas protection circuit, and an oil pillow negative pressure warning circuit in a transformer system according to an embodiment of the present invention;

[0036] Figure 4 It is a schematic diagram of the arrangement of a sealing ring in a transformer system in an embodiment of the present invention.

[0037] In the figure, 100, transformer system; 1, transformer; 2, oil pillow; 3, breathing tube; 4, respirator; 5, monitoring component; 51, valve body; 511, first interface; 512, second interface; 513, third interface; 514, fourth interface; 52, pressure gauge; 53, humidity gauge; 6, sealing ring. DETAILED DESCRIPTION

[0038] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0039] like Figure 1-Figure 2 As shown, a transformer system 100 according to an embodiment of the present invention comprises: a transformer 1, an oil pillow 2, a breathing tube 3, a respirator 4 and a monitoring component 5; the transformer 1 is provided with a heavy gas protection circuit; the oil pillow 2 is connected to the transformer 1, the breathing tube 3 is connected to the oil pillow 2 and the respirator 4, and the monitoring component 5 is connected to the breathing tube 3; the monitoring component 5 comprises a valve body 51, a pressure gauge 52 and a humidity gauge 53; the valve body 51 has a first interface 511, a second interface 512, a third interface 513 and a fourth interface 514, the first interface 511 is connected to the breathing tube 3 and connected to the oil pillow 2, the second interface 512 is connected to the breathing tube 3 and connected to the respirator 4, the pressure gauge 52 is installed at the third interface 513, and the humidity gauge 53 is installed at the fourth interface 514.

[0040] Based on the above technical solution, the oil pillow 2 and the respirator 4 are connected through the breathing tube 3. The monitoring component 5 is connected to the breathing tube 3 so that the pressure gauge 52 and the hygrometer 53 connected to the valve body 51 can measure the pressure and humidity in the breathing tube 3. Since the breathing tube 3 is arranged in the oil pillow 2 and the respirator 4, no matter whether the respirator 4 works normally or not, the pressure gauge 52 and the hygrometer 53 can obtain the pressure and humidity of the oil pillow 2 connected to the breathing tube 3 by measuring the pressure and humidity in the breathing tube 3, and can judge whether the respirator 4 is blocked or other abnormal working abnormalities according to the difference between the pressure value and the atmospheric pressure, thereby avoiding the problem that whether the oil pillow 2 is connected to the outside atmosphere can only be judged based on the breathing phenomenon, but it is impossible to intuitively judge whether the respirator 4 is blocked and whether the pressure in the oil pillow is balanced with the atmospheric pressure; thereby improving the safety of the transformer system 100.

[0041] Furthermore, if Figure 4 As shown, in order to ensure that the measured values ​​of the pressure gauge 52 and the humidity gauge 53 can directly reflect the pressure and humidity in the oil pillow 2; at least two annular sealing rings 6 are provided between the connecting end surfaces between the first interface 511 and the breathing tube 3, and between the connecting end surfaces between the second interface 512 and the respirator 4; the sealing effect of at least two sealing rings 6 can improve the sealing connection effect between the connecting end surfaces, thereby preventing sealing failure and gas leakage.

[0042] Preferably, in this embodiment, in order to facilitate the setting of the sealing ring 6, sealing grooves with the same number as the sealing ring 6 are provided between the connecting end surfaces between the first interface 511 and the breathing tube 3, and between the connecting end surfaces between the second interface 512 and the breathing tube 3, and the sealing ring 6 is sealed in the sealing grooves.

[0043] Furthermore, if Figure 1-Figure 2 As shown, quick connectors are connected between the pressure gauge 52 and the third interface 513, and between the humidity gauge 54 and the fourth interface 514; the quick connector includes a female connector, a male connector and a snap-on component, the female connector is welded to the valve body 51, the male connector is screwed to the pressure gauge 52 or the humidity gauge 53 respectively, the snap-on component can detachably lock the male connector and the female connector, and the snap-on component is located at the periphery of the male connector and the female connector, and the end faces of the male connector and the female connector are sealed and connected; through the provision of the quick connector, the pressure gauge 52 or the humidity gauge 53 can be quickly detached from the valve body 51, which is convenient for replacement and maintenance of the pressure gauge 52 or the humidity gauge 53; at the same time, it can also prevent inaccurate readings caused by poor connection between the pressure gauge 52 or the humidity gauge 53 and the valve body 51 due to frequent disassembly and assembly.

[0044] Furthermore, in order to remotely monitor the transformer system 100, a data transmission module is provided in the pressure gauge 52 and the humidity gauge 53; the data transmission module is used to transmit the readings of the pressure gauge 52 or the humidity gauge 53, thereby transmitting the readings to an external device, so that relevant personnel can monitor multiple transformer systems 100 at the same time to reduce labor costs.

[0045] Furthermore, the transformer 1 is also provided with a light gas protection circuit to perform different protection actions on the transformer 1 according to the operating requirements of the transformers at different voltage levels, thereby enhancing the safety of the transformer system 100 .

[0046] Furthermore, if Figure 3 As shown, the transformer system 100 also includes an anti-mistaken cut-off circuit, which includes a first normally open contact K1 and a relay Q1; the first normally open contact K1 is electrically connected to the pressure gauge 52, and the light gas protection circuit includes a first normally closed contact K2, which is electrically connected to the relay of the light gas outlet tripping circuit; when the negative pressure measured by the pressure gauge 52 reaches a preset value, the first normally open contact K1 is closed, the relay Q1 is energized, the first normally closed contact K2 is disconnected, and the light gas protection outlet tripping circuit is disconnected, so as to prevent air from entering the transformer 1 from the oil leakage point when there is negative pressure inside the transformer 1, causing the light gas protection outlet tripping circuit to malfunction and cut off the power supply of the transformer 1.

[0047] Furthermore, if Figure 3 As shown, it also includes an oil pillow negative pressure warning circuit; the oil pillow negative pressure warning circuit includes a second normally open contact K3, and the second normally open contact K3 is electrically connected to the relay Q1. When the negative pressure measured by the pressure gauge 52 reaches a preset value, the first normally open contact K1 is closed, the relay Q1 is energized, the second normally open contact K3 is closed, and the oil pillow negative pressure warning circuit is connected; therefore, when the pressure measured by the pressure gauge 52 reaches a preset value, the oil pillow negative pressure warning circuit is connected, thereby issuing an early warning to remind the staff to conduct inspection or maintenance.

[0048] The present invention also provides a maintenance method for a transformer system 100, which comprises the following steps:

[0049] S1, read the pressure value measured by the pressure gauge 52, and compare the difference between the reading and the atmospheric pressure with a predetermined value. If the difference is less than the predetermined value, step S2;

[0050] If the difference is greater than a predetermined value, the heavy gas protection circuit in the transformer is first disabled, and then step S2 is performed;

[0051] S2, replacing the silica gel in the respirator 4;

[0052] S3. Depending on whether the heavy gas protection circuit is disabled in step S2, if the heavy gas protection circuit is disabled in step S2, re-enable it.

[0053] Based on the above technical solution, the difference between the pressure in the oil pillow 2 and the atmospheric pressure is used to determine whether to cut off the heavy gas protection circuit before performing breather 4 maintenance, thereby avoiding the problem of increased manpower and management costs and reduced safety of the transformer system 100 caused by directly deactivating the heavy gas protection circuit.

[0054] Furthermore, before step S1, the method further includes the following steps:

[0055] S11, observe the color of the silica gel in the respirator 4, and if the total amount of color change exceeds the set threshold, execute step S1. In this embodiment, the set threshold is 2 / 3 of the total amount of silica gel, so that the replacement and maintenance of the silica gel can be completed before the silica gel completely changes color, avoiding the failure of the respirator due to untimely replacement, resulting in serious consequences such as transformer 1 failure.

[0056] The working process of the present invention is as follows: observe the color of the silica gel in the respirator 4. If the total amount of discoloration exceeds 2 / 3 of the total amount of silica gel, the silica gel in the respirator 4 needs to be replaced and maintained; read the pressure value measured by the pressure gauge 52, and compare the difference between the reading and the atmospheric pressure with a predetermined value. If the difference is less than the predetermined value, directly replace the silica gel in the respirator 4; after the replacement is completed, if the heavy gas protection circuit is disabled, re-enable it; and thus complete the entire maintenance and replacement process.

[0057] In summary, an embodiment of the present invention provides a transformer system 100, which includes a transformer 1, an oil pillow 2, a breathing tube 3, a respirator 4 and a monitoring component 5; the monitoring component 5 includes a valve body 51, a pressure gauge 52 and a hygrometer 53; the valve body 51 has a first interface 511, a second interface 512, a third interface 513 and a fourth interface 514, the first interface 511 is connected to the breathing tube 3 and connected to the oil pillow 2, the second interface 512 is connected to the breathing tube 3 and connected to the respirator 4; the oil pillow 2 and the respirator 4 are connected through the breathing tube 3, and the monitoring component 5 is connected to the breathing tube 3 so that the pressure gauge 52 and the hygrometer 53 connected to the valve body 51 are connected to the breathing tube 3. The pressure gauge 53 can measure the pressure and humidity in the breathing tube 3. Since the breathing tube 3 is arranged in the oil pillow 2 and the respirator 4, no matter whether the respirator 4 works normally or not, the pressure gauge 52 and the humidity gauge 53 can obtain the pressure and humidity of the oil pillow 2 connected to the breathing tube 3 by measuring the pressure and humidity in the breathing tube 3, and can judge whether the respirator 4 is blocked or other abnormal working abnormalities according to the difference between the pressure value and the atmospheric pressure, thereby avoiding the problem of only being able to judge whether the oil pillow 2 is connected to the outside atmosphere based on the breathing phenomenon, but being unable to intuitively judge whether the respirator 4 is blocked and whether the pressure in the oil pillow is balanced with the atmospheric pressure; thereby improving the safety of the transformer system 100.

[0058] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A transformer system, characterized in that: include: Transformers, oil conservators, breathing tubes, respirators and monitoring components; A heavy gas protection circuit is provided in the transformer; The oil pillow is connected to the transformer, the breathing tube is connected to the oil pillow and the breathing apparatus, and the monitoring component is connected to the breathing tube; The monitoring assembly includes a valve body, a pressure gauge and a humidity gauge; The valve body has a first interface, a second interface, a third interface and a fourth interface. The first interface is connected to the breathing tube and connected to the oil pillow. The second interface is connected to the respirator. The pressure gauge is installed at the third interface, and the humidity gauge is installed at the fourth interface.

2. The transformer system according to claim 1, characterized in that: At least two annular sealing rings are provided between the connecting end surfaces of the first interface and the breathing tube, and between the connecting end surfaces of the second interface and the respirator.

3. The transformer system according to claim 1, characterized in that: A quick connector is connected between the pressure gauge and the third interface, and between the humidity gauge and the fourth interface; The quick connector includes a female connector, a male connector and a snap-on component. The female connector is welded to the valve body, and the male connector is screwed to the pressure gauge or the humidity gauge respectively. The snap-on component can detachably lock the male connector and the female connector, and the snap-on component is located at the outer periphery of the male connector and the female connector. The end faces of the male connector and the female connector are sealed and connected.

4. The transformer system according to claim 1, characterized in that: The pressure gauge and the humidity gauge are both provided with a data transmission module; The data transmission module is used to transmit the reading of the pressure gauge or the humidity gauge.

5. The transformer system according to any one of claims 1 to 4, characterized in that: The transformer is also provided with a light gas protection circuit.

6. The transformer system according to claim 5, characterized in that: It also includes an anti-mistaken cut-off circuit, which includes a first normally open contact and a relay; The first normally open contact is electrically connected to the pressure gauge, the light gas protection circuit includes a first normally closed contact, and the first normally closed contact is electrically connected to the relay; When the pressure measured by the pressure gauge reaches a preset value, the first normally open contact is closed, the relay is energized, the first normally closed contact is disconnected, and the light gas protection circuit is disconnected.

7. The transformer system according to claim 6, characterized in that: It also includes a conservator negative pressure warning circuit; The oil pillow negative pressure warning circuit includes a second normally open contact, which is electrically connected to the relay. When the relay is energized, the second normally open contact is closed, and the oil pillow negative pressure warning circuit is connected.

8. A transformer system maintenance method according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, read the pressure value measured by the pressure gauge, and compare the difference between the reading and the atmospheric pressure with a predetermined value. If the difference is less than the predetermined value, step S2; If the difference is greater than a predetermined value, the heavy gas protection circuit in the transformer is first disabled, and then step S2 is performed; S2. Replace the silica gel in the respirator; S3. Depending on whether the heavy gas protection circuit is disabled in step S2, if the heavy gas protection circuit is disabled in step S2, re-enable it.

9. The transformer system maintenance method according to claim 8, characterized in that: Before step S1, the method further includes the following steps: S11, observe the color of the silica gel in the respirator, and if the total amount of color change exceeds the set threshold, execute step S1.

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