Automatic detection device for pressure sealing test of oil-immersed transformer

Abstract

The utility model discloses an automatic detection device for a pressure sealing test of an oil-immersed transformer, and the device comprises an automatic inflation pump which is internally provided with a pressure sensor and a microprocessor; the first end of the three-way pipe connector is connected with the output end of the automatic inflation pump through a hose; one end of the flange pipe connector is connected with the second end of the three-way pipe connector; the other end of the flange pipe connector is hermetically connected with an oil level gauge mounting hole of the oil-immersed transformer to be detected; the electromagnetic exhaust valve is connected with the third end of the three-way pipe connector; wherein the pressure sensor is used for acquiring the internal pressure of the oil-immersed transformer to be tested; and the microprocessor is used for controlling the opening or closing of the automatic inflator pump. According to the automatic detection device for the pressure sealing test of the oil-immersed transformer provided by the embodiment of the utility model, the gas path is shortened, the pressurization, pressure relief and pressure maintaining time and the like are automatic and efficient, the set pressure is accurate and controllable, the state pressure value is monitored in the whole process, and the detection process is safe and stable.

Description

Technical Field

[0001] The utility model relates to the technical field of sealing detection, in particular to an automatic detection device for pressure sealing test of an oil-immersed transformer. Background Art

[0002] With the continuous development of the power industry, the number of oil-immersed transformers put into operation in the power system network has continued to increase, and the number of transformer failures has also increased accordingly. A comprehensive analysis of the causes of failures of domestic oil-immersed transformers shows that a considerable number of failures are caused by poor sealing of oil-immersed transformers. Poor sealing of oil-immersed transformers can easily cause the bushing to become damp, the insulation performance to deteriorate, and cause failures such as coil burnout or even explosion.

[0003] According to the DL / T 264-2022 standard, the gas pressure method is suitable for the pressure seal test (leak test) of oil-immersed transformers installed on site, that is, dry air or nitrogen is used to apply a static pressure of 30kPa on the oil surface at the top of the oil tank. In practice, for the gas source, if an air compressor is used, the initial output pressure is too large and it is not easy to adjust to the target pressure; if a gas cylinder is used, it is not convenient to move and is not conducive to on-site testing. In addition, both have the problem that the gas path from the gas source to the oil-immersed transformer is too long, the pressure valve control is unstable during manual operation, and it is necessary to manually repeatedly pressurize and release the pressure to adjust the test pressure value, and the target pressure value control is not accurate enough. Utility Model Content

[0004] In view of this, an embodiment of the utility model provides an automatic detection device for a pressure sealing test of an oil-immersed transformer, so as to solve the problem in the prior art that when a pressure sealing test of an oil-immersed transformer installed on site is performed manually, the gas path is too long and the control of the manually operated pressure valve is unstable, resulting in insufficiently precise numerical control of the target pressure of the pressure sealing test of the oil-immersed transformer.

[0005] The utility model provides an automatic detection device for pressure sealing test of oil-immersed transformer, comprising:

[0006] Automatic air pump with built-in pressure sensor and microprocessor;

[0007] A three-way pipe connector, a first end of which is connected to the output end of the automatic air pump via a hose;

[0008] A flange pipe connection, one end of which is connected to the second end of the three-way pipe connection; the other end of the flange pipe connection is sealed and connected to the installation hole of the oil level gauge of the oil-immersed transformer to be tested;

[0009] an electromagnetic exhaust valve connected to the third end of the three-way pipe joint;

[0010] The pressure sensor is used to obtain the internal pressure of the oil-immersed transformer to be tested; the microprocessor is used to control the opening or closing of the automatic air pump.

[0011] Optionally, it also includes:

[0012] The air source filter is arranged between the automatic air pump and the three-way pipe joint.

[0013] Optionally, both ends of the air source filter are gas hose quick-connect connectors; wherein, the air inlet end of the air source filter is connected to the automatic air pump through a hose; and the air outlet end of the air source filter is connected to the first end of the three-way pipe connector.

[0014] Optionally, a filter element, a pressure regulating valve, a filter, a protective cover, a drain port and a pressure gauge are provided inside the air source filter.

[0015] Optionally, the electromagnetic exhaust valve is electrically connected to a microprocessor; wherein the microprocessor is used to control the opening or closing of the electromagnetic exhaust valve.

[0016] Optionally, it also includes:

[0017] The muffler is arranged at the outlet end of the electromagnetic exhaust valve.

[0018] Optionally, the upper port connected to the flange pipe joint and the three-way pipe joint and the lower port connected to the oil level gauge mounting hole of the oil-immersed transformer to be tested are both threaded interfaces.

[0019] Optionally, it also includes:

[0020] The sealing gasket is arranged between the lower port of the flange pipe connection and the installation hole of the oil level gauge of the oil-immersed transformer to be tested.

[0021] Optionally, the automatic air pump includes: a display screen and interactive buttons.

[0022] Beneficial effects of the utility model:

[0023] The embodiment of the utility model provides an automatic detection device for pressure sealing test of oil-immersed transformers, and its principle is: through the pressure sensing module, it is judged whether the internal pressure value of the oil transformer reaches the set value, and the feedback is given to the microprocessor, and the microprocessor controls the opening or closing of the air pump. Before it is lower than the set value, the air pump is automatically turned on for pressurized inflation, and the air pump is immediately turned off after reaching the set value. When the internal pressure of the oil transformer is higher than the set value, the solenoid valve is automatically turned on to release the pressure and reduce the pressure to the set value. The processor replaces manual pressurization, pressure relief, and pressure maintenance detection throughout the test, and only needs to set the target air pressure and test time, so as to achieve the effect of safe, simple and accurate detection process. Compared with the existing detection devices with problems such as too long gas path, unstable pressure control, inaccurate values, and reliance on manual experience, the automatic detection device for pressure sealing test of oil-immersed transformers provided by the embodiment of the utility model shortens the gas path, reduces the gas path fold line, improves the gas path efficiency, ensures the safety of the gas path, improves the stability and reliability of pressure control, and achieves automatic and efficient effects in pressurization, pressure relief, and pressure maintenance time. The set pressure is accurately controllable, the state pressure value is monitored throughout the process, and the detection process is safe and stable.

[0024] The present embodiment provides an automatic detection device for the pressure sealing test of an oil-immersed transformer, which adopts an automatic air pump, a hose, an air source filter, a three-way pipe connection, a flange pipe connection, an electromagnetic exhaust valve and a muffler. Most of the components are small and light, easy to carry, and easy to install, which can meet the flexibility requirements of on-site installation and testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the accompanying drawings:

[0026] Figure 1 It shows a structural diagram of an automatic detection device for pressure sealing test of an oil-immersed transformer in an embodiment of the utility model;

[0027] Figure 2 The present invention shows a working flow chart of an automatic detection device for pressure sealing test of an oil-immersed transformer in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0029] Example 1

[0030] like Figure 1 As shown, the embodiment of the utility model provides an automatic detection device for the pressure sealing test of an oil-immersed transformer, comprising an automatic air pump 1, a three-way pipe connection 2, a hose 3, a flange pipe connection 4 and an electromagnetic exhaust valve 5, wherein the automatic air pump 1 is connected to the first end of the three-way pipe connection 2 through the hose 3, the second end of the three-way pipe connection 2 is connected to one end of the flange pipe connection 4, the third end of the three-way pipe connection 2 is connected to the electromagnetic exhaust valve 5, and the other end of the flange pipe connection 4 is sealed and connected to the oil level gauge mounting hole of the oil-immersed transformer 6 to be tested. Among them, a pressure sensor and a microprocessor are provided inside the automatic air pump 1, the pressure sensor is used to detect the air pressure value of the air circuit, and the microprocessor is used to control the opening or closing of the automatic air pump for air intake pressurization.

[0031] In a specific embodiment, the electromagnetic exhaust valve is connected to an external wire 7 of the microprocessor, and the opening or closing of the electromagnetic exhaust valve is directly controlled by the microprocessor.

[0032] In a specific implementation, the three ports of the three-way pipe connection are all threaded ports. The flange pipe connection is fixedly installed and connected to the mounting hole of the oil level gauge of the oil-immersed transformer to be tested through threads, and a sealing gasket is arranged between the two to ensure air tightness.

[0033] In order to better understand the principle and working process of this patent, Figure 2 As shown, the working principle of the automatic detection device for pressure sealing test of oil-immersed transformer in this embodiment is as follows: the pressure sensor detects the air pressure of the gas circuit, the microprocessor determines whether the pressure value of the gas circuit reaches the set value, and the microprocessor controls the opening or closing of the air pump. Before it is lower than the set value, the air pump is automatically turned on for pressurized inflation, and the air pump is immediately turned off after reaching the set value. When the internal pressure of the oil transformer is higher than the set value, the solenoid valve is automatically opened to release the pressure and reduce the pressure to the set value. If the gas circuit of the oil-immersed transformer maintains a stable air pressure for a certain period of time, it passes the pressure sealing test, otherwise it fails the test.

[0034] The processor replaces manual work in the whole process of the test to perform pressurization, pressure relief, and pressure maintenance tests. It only needs to set the target air pressure and test duration through the display screen and interactive buttons connected to the microprocessor, so as to achieve a safe, simple, and accurate detection process. Compared with the existing detection devices that have problems such as too long gas path, unstable pressure control, inaccurate values, and reliance on manual experience, the automatic detection device for pressure sealing test of oil-immersed transformers provided by the embodiment of the utility model shortens the gas path, reduces the gas path fold line, improves the gas path efficiency, ensures the safety of the gas path, and improves the stability and reliability of pressure control. It achieves automatic and efficient effects in pressurization, pressure relief, and pressure maintenance time, and the set pressure is accurately controllable, the state pressure value is monitored throughout the process, and the detection process is safe and stable.

[0035] It should be noted that this embodiment uses the existing functions of the microprocessor and does not make any improvements to the microprocessor itself. This patent protects the main structure of the detection device.

[0036] Example 2

[0037] The difference between this embodiment and embodiment 1 is that an air source filter 8 is provided between the automatic air pump 1 and the three-way pipe connection 2, and both ends of the air source filter 8 are gas hose quick-connect joints. The air inlet end of the air source filter 8 is connected to the automatic air pump 1 through the hose 3; the air outlet end of the air source filter 8 is connected to the first end of the three-way pipe connection. The air source filter is provided with a filter element, a pressure regulating valve, a filter, a protective cover, a drain port and a pressure gauge. The air source filter is used to clean the air source and can filter the moisture in the compressed air to prevent the moisture from entering the device with the gas.

[0038] Taking into account the convenience of installation, the three-way pipe joint is fixedly connected to the air outlet end of the air source filter through a threaded port, and the air inlet end of the air source filter is connected to the automatic air pump through a hose.

[0039] Example 3

[0040] The difference between this embodiment and the above-mentioned embodiment is that a muffler 9 is provided at the exhaust port of the electromagnetic exhaust valve 5 to eliminate noise during exhaust.

[0041] With the automatic air pump as the core, the pressurization, pressure relief and pressure holding time of the gas circuit are controlled. The oil-immersed transformer to be tested is connected to the detection device through flange pipe connection and three-way pipe connection. According to the air charging circuit, the automatic air charging pump is at the front end, followed by the connecting hose, air source filter, three-way pipe connection, flange pipe connection, and oil-immersed transformer to be tested. According to the exhaust gas circuit, starting from the oil-immersed transformer to be tested, it is followed by flange pipe connection, three-way pipe connection, electromagnetic exhaust valve, and muffler.

[0042] The present embodiment provides an automatic detection device for the pressure sealing test of an oil-immersed transformer, which adopts an automatic air pump, a hose, an air source filter, a three-way pipe connection, a flange pipe connection, an electromagnetic exhaust valve and a muffler. Most of the components are small and light, easy to carry, and easy to install, which can meet the flexibility requirements of on-site installation and testing.

[0043] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. An automatic detection device for pressure sealing test of oil-immersed transformer, characterized in that: include: Automatic air pump with built-in pressure sensor and microprocessor; A three-way pipe connector, a first end of which is connected to the output end of the automatic air pump via a hose; A flange pipe connection, one end of which is connected to the second end of the three-way pipe connection; the other end of the flange pipe connection is sealed and connected to the installation hole of the oil level gauge of the oil-immersed transformer to be tested; an electromagnetic exhaust valve connected to the third end of the three-way pipe joint; Wherein, the pressure sensor is used to obtain the internal pressure of the oil-immersed transformer to be tested; and the microprocessor is used to control the opening or closing of the automatic air pump.

2. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 1 is characterized in that: Also includes: The air source filter is arranged between the automatic air pump and the three-way pipe joint.

3. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 2 is characterized in that: Both ends of the air source filter are gas hose quick-connect connectors; wherein, the air inlet end of the air source filter is connected to the automatic air pump through the hose; and the air outlet end of the air source filter is connected to the first end of the three-way pipe connector.

4. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 3 is characterized in that: The air source filter is internally provided with a filter element, a pressure regulating valve, a filter, a protective cover, a drain port and a pressure gauge.

5. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 1 is characterized in that: The electromagnetic exhaust valve is electrically connected to the microprocessor; wherein the microprocessor is used to control the opening or closing of the electromagnetic exhaust valve.

6. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 1 is characterized in that: Also includes: A muffler is arranged at the outlet end of the electromagnetic exhaust valve.

7. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 1 is characterized in that: The upper port of the flange pipe joint connected to the three-way pipe joint and the lower port connected to the oil level gauge mounting hole of the oil-immersed transformer to be tested are both threaded interfaces.

8. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 7 is characterized in that: Also includes: A sealing gasket is arranged between the lower port of the flange pipe connection and the installation hole of the oil level gauge of the oil-immersed transformer to be tested.

9. The automatic detection device for pressure sealing test of oil-immersed transformer according to claim 1, characterized in that: The automatic air pump comprises: a display screen and interactive buttons.

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