A temperature measuring device for transformer winding capable of temperature self-compensation and a method of using the same

Abstract

The present invention discloses a temperature self-compensating transformer winding temperature measuring device and a method of using the same, and relates to the technical field of transformer winding temperature measurement, including a measuring box shell, wherein the measuring box shell is provided with a top space and a bottom space, wherein a driving wheel is rotatably connected in the top space, wherein a Bourdon spring is sleeved on the surface of the driving wheel, and the head end of the Bourdon spring is fixedly connected to the surface of the driving wheel. The temperature self-compensating transformer winding temperature measuring device and a method of using the same of the present invention, when the transformer is unloaded, samples the top oil temperature of the transformer through a temperature sensing package, a Bourdon spring and a capillary tube, and when the transformer is loaded, simulates the oil temperature rise through a current matcher and an isolation tube, and at the same time, a Pt100 probe also measures the oil temperature change, and each group of measurement data differs and the winding temperature average is calculated, which is conducive to accurately measuring the transformer winding temperature and also conducive to reducing the measurement deviation of the measuring device.

Description

Technical Field

[0001] The invention relates to the technical field of transformer winding temperature measurement, and in particular to a transformer winding temperature measurement device capable of temperature self-compensation and a use method thereof. Background Art

[0002] The reliability of transformer operation is directly related to the economic operation, safety and stability of the power grid. When the transformer is running, the temperature of the transformer winding is directly related to the life of the transformer insulation material. The aging of the insulation material affects the operation of the transformer, so it is particularly important to monitor the transformer winding temperature.

[0003] The existing transformer winding temperature cannot be directly measured. The current temperature measurement methods can be divided into direct measurement method, indirect calculation method and thermal simulation measurement method. Among them, the thermal simulation method is the most widely used. Usually, a transformer winding temperature controller is used. Its measurement principle is mainly based on the relationship between the load loss and load current of the transformer. On the basis of the top oil temperature, a copper-oil temperature difference is superimposed by a thermal matcher. The temperature of the winding is expressed by temperature superposition. The thermal simulation method makes up for the problem of inaccurate actual temperature measurement by traditional thermometers. However, changes in ambient temperature are likely to affect changes in transformer oil temperature, thereby affecting the accuracy of the transformer winding temperature controller measurement results.

[0004] In order to solve the deficiencies of the prior art, we propose a transformer winding temperature measurement device capable of temperature self-compensation and a method of using the same. Summary of the invention

[0005] The main purpose of the present invention is to provide a transformer winding temperature measurement device capable of temperature self-compensation and a method of using the same, which can effectively solve the problems in the background technology.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A transformer winding temperature measuring device capable of temperature self-compensation comprises a measuring box shell, wherein a top space and a bottom space are provided inside the measuring box shell, a driving wheel is rotatably connected in the top space, a Bourdon spring is sleeved on the surface of the driving wheel, a head end of the Bourdon spring is fixedly connected to the surface of the driving wheel, a capillary is fixedly connected to the end of the Bourdon spring, a temperature sensing package is fixedly connected to the end of the capillary, kerosene is filled in the temperature sensing package, a shaft rod is detachably connected to the axis of the driving wheel, a scale plate is installed on the top of the shaft rod, a temperature pointer is fixedly connected to the top of the shaft rod, a terminal board is detachably connected to the bottom space, a Pt100 probe is provided on the terminal board through an external wire, the temperature sensing package and the Pt100 probe are sleeved on the outside of the same isolation tube, a temperature sensing tube is sleeved on the outside of the isolation tube, a mounting joint is detachably connected to the top of the temperature sensing tube, a hose is fixedly connected to the top of the mounting joint, and the external wires of the capillary and the Pt100 probe pass through the hose and the mounting joint.

[0008] Preferably, a mounting column is sleeved on the outer side of the shaft rod, a movable pointer is installed on the top of the mounting column, a mounting plate is fixedly connected to the outer side of the mounting column, an alarm device is fixedly connected to the top surface of the mounting plate, the alarm device includes an alarm, a switch piece is installed on the inner side of the alarm, an alarm pointer device is installed on the outer surface of the mounting column, the alarm pointer device includes a connecting piece, the connecting piece is embedded with the switch piece, the top surface of the connecting piece is detachably connected to a connecting rod, and the top of the connecting rod is fixedly connected to the pointer plate.

[0009] Preferably, a plurality of alarm devices are fixedly connected to the top surface of the mounting plate, a plurality of alarm pointer devices are installed on the outer side of the mounting column, and a through groove is opened on the surface of part of the connecting piece.

[0010] Preferably, the front end of the switch piece is rotatably connected to a rubber wheel, the shape of the connecting piece is set to be arc-shaped, and a limiting column is installed on the outer side of the switch piece.

[0011] Preferably, a shunt head is installed at the connection between the capillary tube and the Bourdon spring, a first shunt tube is fixedly connected to the outside of the shunt head, and a cavity is fixedly connected to the end of the first shunt tube.

[0012] Preferably, a gear ring is installed on the outside of the Bourdon spring, a rack is slidably connected to the inner wall of the top space, the rack is engaged with the gear ring, a slide slot bin is installed at the end of the rack, and a No. 2 shunt pipe is arranged on the outside of the slide slot bin.

[0013] Preferably, the top surface and the bottom surface of the driving wheel are both rotatably connected with a plurality of rollers.

[0014] A method for using a transformer winding temperature measuring device capable of temperature self-compensation is used to implement a transformer winding temperature measuring device capable of temperature self-compensation, specifically comprising the following steps:

[0015] S1: Insert the temperature sensing tube into the oil hole of the transformer, rotate the installation joint, fix the position of the temperature sensing tube, the transformer is without load and the winding is not heated, according to the thermal expansion and contraction of the kerosene in the temperature sensing package, the Bourdon spring drives the temperature pointer to rotate, and the top oil temperature of the transformer is measured, which is recorded as the first measurement;

[0016] S2: Transformer load, simulating winding heating, the current sensor outputs a current proportional to the load, the current flows through the isolation tube via the current matcher, the isolation tube increases the temperature of the temperature-sensing package, and the displacement of the Bourdon spring is expanded, thereby measuring the sum of the transformer top oil temperature and the winding temperature, which is recorded as the second measurement;

[0017] S3: At the same time, the Pt100 probe also measures the transformer top oil temperature when the transformer is loaded or not, or the sum of the transformer top oil temperature and the winding temperature, which are recorded as the third and fourth measurements;

[0018] S4: The difference between the first and second measurements is the winding temperature. Similarly, the difference between the third and fourth measurements is also the winding temperature. Then the average value of the two sets of winding temperatures is calculated.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. In the present invention, by setting the temperature-sensing package, Bourdon spring and capillary tube, when the transformer is unloaded and the winding is not heated, the top oil temperature inside the transformer is sampled, and then the oil temperature rise is simulated by the current matcher and the isolation tube, which is conducive to accurately measuring the transformer winding temperature and improving the measurement accuracy of the winding temperature measuring device.

[0021] 2. In the present invention, the temperature change is measured by setting a Pt100 probe and the characteristic of the copper drum resistance change of the Pt100 probe. The measurements are performed with and without load on the transformer respectively. The two sets of measurement data are subtracted and the average value is calculated with the data measured by the temperature pointer method, which is beneficial to reduce the error of measuring the winding temperature value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the measuring device of the present invention;

[0023] Figure 2 is a flow chart of a method for using the measuring device of the present invention;

[0024] Figure 3 It is a schematic diagram of the top space related structure of the present invention;

[0025] Figure 4 It is a schematic diagram of the relevant structure of the alarm pointer device of the present invention;

[0026] Figure 5 It is a schematic diagram of the relevant structure of the alarm device of the present invention;

[0027] Figure 6 It is a schematic diagram of the related structure of the movable pointer of the present invention;

[0028] Figure 7 It is a schematic diagram of the structure of the temperature sensing tube of the present invention;

[0029] Figure 8 is a schematic diagram of the relevant structure of the driving wheel of the present invention;

[0030] Fig. 9 It is a schematic diagram of the gear change related structure of the present invention.

[0031] In the figure:

[0032] 1. Measuring box shell; 11. Top space; 12. Driving wheel; 13. Bourdon spring; 14. Capillary; 15. Temperature-sensing package; 16. Shaft; 17. Scale plate; 18. Temperature pointer; 2. Bottom space; 21. Terminal board; 22. Pt100 probe; 23. Isolation tube; 24. Temperature-sensing tube; 3. Mounting joint; 31. Hose; 4. Mounting column; 41. Movable pointer; 42. Mounting plate; 5. Alarm device; 51. Alarm; 52. Switch plate; 6. Alarm pointer device; 61. Connecting plate; 62. Connecting rod; 63. Pointer plate; 64. Through groove; 7. Rubber wheel; 71. Limiting column; 8. Diverter head; 81. No. 1 diverter tube; 82. Cavity body; 83. Gear ring; 84. Rack; 85. Slide bin; 86. No. 2 diverter tube; 9. Roller. DETAILED DESCRIPTION

[0033] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0034] A transformer winding temperature measuring device capable of temperature self-compensation comprises a measuring box shell 1, wherein a top space 11 and a bottom space 2 are provided inside the measuring box shell 1, a driving wheel 12 is rotatably connected in the top space 11, a Bourdon spring 13 is sleeved on the surface of the driving wheel 12, a head end of the Bourdon spring 13 is fixedly connected to the surface of the driving wheel 12, a capillary 14 is fixedly connected to the end of the Bourdon spring 13, a temperature sensing package 15 is fixedly connected to the end of the capillary 14, kerosene is filled in the temperature sensing package 15, a shaft 16 is detachably connected to the axis of the driving wheel 12, and a top of the shaft 16 is fixedly connected to the end of the capillary 14. A scale plate 17 is installed, a temperature pointer 18 is fixedly connected to the top of the shaft 16, a terminal board 21 is detachably connected to the bottom space 2, a Pt100 probe 22 is provided on the terminal board 21 through an external wire, the temperature sensing package 15 and the Pt100 probe 22 are sleeved with the same isolation tube 23 on the outside, a temperature sensing tube 24 is sleeved on the outside of the isolation tube 23, a mounting joint 3 is detachably connected to the top of the temperature sensing tube 24, a hose 31 is fixedly connected to the top of the mounting joint 3, and the external wires of the capillary 14 and the Pt100 probe 22 pass through the hose 31 and the mounting joint 3.

[0035] like Figure 1 and Figure 3 As shown, the interior of the measuring box shell 1 can be divided into a top space 11 and a bottom space 2, wherein in the top space 11, the driving wheel 12 is rotatably connected at the bottom surface of the top space 11, and the Bourdon spring 13 is sleeved on the shaft of the driving wheel 12. One end of the Bourdon spring 13 is fixedly connected to the shaft of the driving wheel 12, and the other end is fixedly connected with a capillary 14. The end of the capillary 14 is connected to a temperature sensing bag 15. The interior of the temperature sensing bag 15 is a cavity filled with kerosene. The temperature sensing bag 15 is sleeved inside an isolation tube 23. The isolation tube 23 is an externally wrapped heater, which can provide temperature compensation for the temperature sensing bag 15. When the temperature of the temperature sensing bag 15 rises, under the action of thermal expansion and contraction, the kerosene moves from the temperature sensing bag 15 along the capillary 14 to the Bourdon spring 13, so that the Bourdon spring 13 expands outward on the surface of the driving wheel 12, and the Bourdon spring 13 moves, so that the Bourdon spring 13 drives the driving wheel 12 to rotate;

[0036] like Figure 4 As shown, the bottom end of the shaft 16 is detachably connected to the axis of the driving wheel 12, the edge of the scale plate 17 is threadedly connected to the top port of the top space 11 by screws, the surface of the scale plate 17 is engraved with numbers and scales of different sizes, the top surface of the shaft 16 is flush with the surface of the scale plate 17, the temperature pointer 18 is installed at the top axis of the shaft 16 by screws, and the driving wheel 12 can rotate on the upper surface of the scale plate 17 with the temperature pointer 18 through the shaft 16;

[0037] like Figure 1 and Figure 7As shown, in the bottom space 2, the terminal board 21 is installed on the bottom surface of the bottom space 2 by screws, and the terminal board 21 is connected to the potentiometer and the Pt100 probe 22 and other components by external wires, and each forms a complete circuit. The Pt100 probe 22 is based on the principle of platinum resistance thermometer, and uses the resistance change characteristics of platinum resistance material when the temperature changes to measure the temperature. The measuring box shell 1 is provided with a temperature transmitter and a display device, and the Pt100 probe 22 is connected to the temperature transmitter, and a DC signal is output to the display device through the temperature transmitter, so as to complete the digital display reading;

[0038] like Figure 7 As shown, the temperature sensing package 15 and the Pt100 probe 22 are inserted into the same isolation tube 23 wound around the heater, and then the isolation tube 23 is inserted into the temperature sensing tube 24. The isolation tube 23 can also prevent the insulating oil from directly contacting the components. The top of the temperature sensing tube 24 is detachably connected with a mounting joint 3, and the side of the mounting joint 3 away from the temperature sensing tube 24 is fixedly connected with a hose 31. The end of the hose 31 is detachably connected to the measuring box shell 1. The hose 31 wraps part of the capillary 14 and the external wires of the Pt100 probe 22, and the hose 31 plays the effect of protecting the capillary 14 and the external wires.

[0039] When the transformer is not loaded and the winding is not heated, the kerosene in the temperature-sensing package 15 expands and contracts, and the kerosene moves along the capillary 14. The temperature-sensing package 15 transmits the pressure to the Bourdon spring 13 through the capillary 14, causing the Bourdon spring 13 to contract on the surface of the driving wheel 12, thereby causing the Bourdon spring 13 to drive the temperature pointer 18 to move on the surface of the scale plate 17 through the shaft 16. The temperature scale indicated by the temperature pointer 18 is the oil temperature of the top oil tank of the transformer, which is recorded as T0;

[0040] The measuring box shell 1 is provided with a current sensor and a current matcher. When the transformer is loaded, the winding is simulated to heat up. The current sensor outputs a current proportional to the load. The current flows through the isolation tube 23 after the current matcher, causing the isolation tube 23 to heat up. The isolation tube 23 further heats the temperature-sensing package 15, and the displacement of the Bourdon spring 13 is enlarged, so that the position indicated by the temperature pointer 18 also changes accordingly. The temperature scale indicated by the temperature pointer 18 is the sum of the transformer oil temperature and the winding temperature, which is recorded as T1; that is, the winding temperature is:

[0041] ΔT0 = T1 - T2;

[0042] The Pt100 probe 22 is inserted into the oil hole synchronously with the temperature sensing tube 24. The linear function relationship between the resistance value of Pt100 and the temperature is:

[0043] R T =R0+K·T;

[0044] R0 is the resistance value of the resistor at 0℃. Generally, the resistance value of R0 is 100Ω. K is the coefficient of resistance change with temperature. Generally, K=0.385Ω / ℃. T is the resistance value of the resistor at T℃, so the solution formula for T can be converted to:

[0045]

[0046] The Pt100 probe 22 is connected to the temperature transmitter. The temperature transmitter substitutes the input resistance value according to the above formula to obtain the T value, and transmits the output T value to the display device to complete the digital reading. When the transformer is not under negative pressure, the first reading according to the display device is recorded as T3. When the transformer is under negative pressure, the second reading according to the display device is recorded as T4, that is, the winding temperature is

[0047] ΔT1 = T3 - T4;

[0048] According to the above two winding temperatures ΔT0 and ΔT1, the average winding temperature is calculated. Right now:

[0049]

[0050] like Figure 4-Figure 5 As shown, the edge of the mounting plate 42 is detachably connected to the inner wall of the top space by screws, and the alarm 51 is fixedly connected to the top surface of the mounting plate 42, wherein the switch piece 52 is a spring piece, the tail of the switch piece 52 is connected to the inner side of the alarm 51, and the head of the switch piece 52 does not contact the inner side of the alarm 51. When stationary, the entire switch piece 52 forms an angle with the inner side of the alarm 51. A start end is installed on the inner surface of the alarm 51, and the start end can start the alarm 51 to run. The inner surface of the switch piece 52 does not contact the start end, so a complete alarm circuit cannot be formed;

[0051] like Figure 4-Figure 6 As shown, the connecting piece 61 is rotatably connected to the outer surface of the mounting column 4, the head end of the pointer plate 63 extends to the edge of the scale plate 17, and the head end points to the scale temperature on the scale plate 17, that is, the alarm temperature. The tail end of the pointer plate 63 is round, and the tail end is sleeved on the top of the mounting column 4 and rotatably connected, so the position of the head end of the pointer plate 63 on the scale plate 17 can be changed to set different alarm temperatures. The connecting rod 62 connects the connecting piece 61 and the pointer plate 63;

[0052] like Figure 6 As shown, the end of the movable pointer 41 is located at the top of the mounting column 4 and is fixedly connected to the surface of the shaft 16. The movable pointer 41 moves synchronously with the temperature pointer 18. At the same time, the head end of the movable pointer 41 and the head end of the pointer plate 63 are on the edge line of the same circle.

[0053] During operation, if the active pointer 41 is not in contact with the pointer plate 63, it means that the temperature pointer 18 has not reached the set alarm temperature, and the alarm device 5 is in a disconnected circuit; if the active pointer 41 is in contact with the pointer plate 63, and the connecting piece 61 is pushed to move by the pointer plate 63 and the connecting rod 62, so that the connecting piece 61 is in contact with the switch piece 52, so that the switch piece 52 moves inward and contacts the starting end, the alarm device 5 is in a complete circuit, the alarm 51 is connected to the terminal board 21 through an external wire, the working signal of the alarm 51 is transmitted to the remote control end, and an alarm message is given, which means that the temperature pointer 18 has passed the set alarm temperature.

[0054] like Figure 4-Figure 5 As shown, a plurality of alarm devices 5 can also be fixedly connected to the top surface of the mounting plate 42, and a plurality of alarm pointer devices 6 can be installed on the outer side of the mounting column 4, each alarm pointer device 6 corresponds to the alarm device 5, and the connecting pieces 61 in different alarm pointer devices 6 are located at different positions on the mounting column 4. For example, the alarm pointer devices 6 can be set to four groups, and the temperature range on the scale plate 17 is divided into four parts. Each group of pointer plates 63 can move within its own temperature range. The colors of the first ends of the four groups of pointer plates 63 are red, blue, green and yellow, respectively. The connecting pieces 61 corresponding to the four groups of pointer plates 63 are blue, green, red and yellow from bottom to top on the mounting column 4, and the surfaces of the green and red connecting pieces 61 are opened. There is a through groove 64, and the connecting rod 62 at the bottom of the green pointer plate 63 is connected to its own connecting piece 61 through the through groove 64 of the red connecting piece 61. At the same time, the connecting rod 62 at the bottom of the blue pointer plate 63 is connected to its own connecting piece 61 through the through groove 64 of the red connecting piece 61 and the green connecting piece 61. A switch piece 52 is arranged on the inner side of each alarm 51, and each switch piece 52 is at a different height level. The corresponding connecting pieces 61 of the four groups of pointer plates 63 are all engaged with the corresponding switch pieces 52, so as to ensure that each alarm device 5 and alarm pointer device 6 works normally. By setting multiple groups of alarm devices 5 and alarm pointer devices 6, it is beneficial to improve the effect of monitoring the winding temperature.

[0055] like Figure 5 As shown, the shape of the connecting piece 61 is set to be arc-shaped, and a rubber wheel 7 is installed at the front end of the switch piece 52 and the rubber wheel 7 is rotatable, which is convenient for reducing the friction at the contact between the connecting piece 61 and the switch piece 52 and improving the smoothness of the rotation of the connecting piece 61. At the same time, a limiting column 71 is also provided on the outer side of the switch piece 52, and the bottom end of the limiting column 71 is detachably connected to the mounting plate 42. The limiting column 71 is used to limit the outward expansion distance of the switch piece 52 to ensure that when the connecting piece 61 contacts the switch piece 52, the switch piece 52 can move inward and contact the starting end of the alarm 51.

[0056] like Figure 3As shown, a diverter head 8 is provided at the connection between the capillary 14 and the Bourdon spring 13. The diverter head 8 connects the capillary 14 to a No. 1 diverter tube 81. The material of the No. 1 diverter tube 81 is the same as that of the capillary 14. At the same time, a cavity body 82 is fixedly connected to the end of the No. 1 diverter tube 81. A cavity is provided inside the cavity body 82. When the temperature sensing package 15 pushes pressure toward the capillary 14, the pressure causes the kerosene to move in the capillary 14. Part of the kerosene moves to the inside of the cavity body 82 through the diverter head 8 and the No. 1 diverter tube 81, thereby reducing the impact of the kerosene flowing in the capillary 14, which is beneficial to improving the stability of the contraction of the Bourdon spring 13.

[0057] like Fig. 9 As shown, a gear ring 83 can also be installed on the outside of the Bourdon spring 13, and the gear ring 83 is rotatably connected to the inner wall of the top space 11, wherein one end of the Bourdon spring 13 is fixedly connected to the inner side of the gear ring 83, and the other end is fixedly connected to the shaft of the driving wheel 12, the rack 84 is slidably connected to the inner wall of the top space 11, the rack 84 is engaged with the gear ring 83, and the end of the rack 84 is slidably connected in the chute bin 85, one end of the second shunt pipe 86 is connected to the shunt head 8, and the other end is connected to the chute bin 85, the heat of the kerosene The expansion and contraction affect the extension and retraction of the tail of the rack 84 in the chute bin 85 through the No. 2 shunt pipe 86. If the rack 84 extends out of the chute bin 85, the rack 84 pushes the gear ring 83 to rotate clockwise, and the Bourdon spring 13 moves outward. Conversely, the rack 84 retracts into the chute bin 85, the rack 84 pushes the gear ring 83 to rotate counterclockwise, and the Bourdon spring 13 moves inward, which is used to assist the normal contraction of the Bourdon spring 13 and reduce the deformation of the Bourdon spring 13 due to long-term use, which is beneficial to provide the accuracy of the winding temperature measurement.

[0058] like Figure 8 As shown, a plurality of rollers 9 are evenly distributed on the top and bottom surfaces of the driving wheel 12. When the Bourdon spring 13 contracts, the rotation of the rollers 9 is beneficial to reducing the friction between the Bourdon spring 13 and the driving wheel 12, and reducing the influence of the friction on the contraction distance of the Bourdon spring 13, thereby helping to improve the accuracy of the winding temperature measuring device.

[0059] like Figure 2 As shown, a method for using a transformer winding temperature measuring device capable of temperature self-compensation is used to implement a transformer winding temperature measuring device capable of temperature self-compensation, specifically comprising the following steps:

[0060] S1: The temperature sensing tube 24 is inserted into the oil hole of the transformer, and the joint 3 is rotated to fix the position of the temperature sensing tube 24. The transformer is unloaded and the winding is not heated. According to the thermal expansion and contraction of the kerosene in the temperature sensing package 15, the Bourdon spring 13 drives the temperature pointer 18 to rotate, thereby measuring the top oil temperature of the transformer, which is recorded as the first measurement;

[0061] S2: Transformer load, simulating the heating of the winding, the current sensor outputs a current proportional to the load, the current flows through the isolation tube 23 via the current matcher, the isolation tube 23 increases the temperature of the temperature-sensing package 15, and the displacement of the Bourdon spring 13 is enlarged, thereby measuring the sum of the transformer top oil temperature and the winding temperature, which is recorded as the second measurement;

[0062] S3: At the same time, the Pt100 probe 22 also measures the transformer top oil temperature when the transformer is loaded or not, or the sum of the transformer top oil temperature and the winding temperature, which are recorded as the third measurement and the fourth measurement;

[0063] S4: The difference between the first and second measurements is the winding temperature. Similarly, the difference between the third and fourth measurements is also the winding temperature. Then the average value of the two sets of winding temperatures is calculated.

[0064] It should be noted that the present invention is a transformer winding temperature measurement device capable of temperature self-compensation and a method of using the same. Figure 1-Figure 9 As shown, when in use, an oil hole is provided on the top surface of the top oil tank of the transformer, the entire temperature sensing tube 24 is inserted into the oil hole, and the joint 3 is rotated to fix the position of the temperature sensing tube 24 on the top layer of the transformer. When the transformer is not loaded and the winding is not heated, the kerosene in the temperature sensing package 15 expands and contracts, and the Bourdon spring 13 is displaced through the capillary 14. The temperature indicated by the temperature pointer 18 is the oil temperature at the top of the transformer. Similarly, the temperature measured by the Pt100 probe 22 and read on the display device is also the oil temperature at the top of the transformer. When the transformer is under negative pressure, the current sensor, The current matcher makes the isolation tube 23 heat up to simulate the heating of the winding. The isolation tube 23 heats up the temperature-sensing package 15, which expands the displacement of the Bourdon spring 13. At this time, the temperature indicated by the temperature pointer 18 is the sum of the oil temperature at the top of the transformer and the winding temperature. Similarly, the temperature measured by the Pt100 probe 22 and read on the display device is also the sum of the oil temperature at the top of the transformer and the winding temperature. The subtraction of the two values ​​measured by the temperature pointer 18 is the winding temperature, and the subtraction of the two values ​​measured by the Pt100 probe 22 is also the winding temperature. Finally, the average value of the two sets of winding temperature values ​​is calculated.

[0065] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A transformer winding temperature measuring device capable of temperature self-compensation, characterized in that: The measuring box shell (1) comprises a top space (11) and a bottom space (2) formed inside the measuring box shell (1); a driving wheel (12) is rotatably connected inside the top space (11); a Bourdon spring (13) is sleeved on the surface of the driving wheel (12); the head end of the Bourdon spring (13) is fixedly connected to the surface of the driving wheel (12); a capillary tube (14) is fixedly connected to the end of the Bourdon spring (13); a temperature sensing package (15) is fixedly connected to the end of the capillary tube (14); kerosene is filled in the temperature sensing package (15); a shaft (16) is detachably connected to the axis of the driving wheel (12); a scale plate (17) is installed on the top of the shaft (16); The top of the shaft (16) is fixedly connected to a temperature pointer (18), the bottom space (2) is detachably connected to a terminal board (21), the terminal board (21) is provided with a Pt100 probe (22) via an external wire, the temperature sensing package (15) and the Pt100 probe (22) are sleeved with the same isolation tube (23) on the outside, the isolation tube (23) is sleeved with a temperature sensing tube (24) on the outside, the top of the temperature sensing tube (24) is detachably connected to a mounting joint (3), the top of the mounting joint (3) is fixedly connected to a hose (31), and the external wires of the capillary (14) and the Pt100 probe (22) pass through the hose (31) and the mounting joint (3).

2. A transformer winding temperature measuring device capable of temperature self-compensation according to claim 1, characterized in that: The shaft rod (16) is sleeved with a mounting column (4) on the outside, a movable pointer (41) is installed on the top of the mounting column (4), a mounting plate (42) is fixedly connected to the outside of the mounting column (4), an alarm device (5) is fixedly connected to the top surface of the mounting plate (42), the alarm device (5) comprises an alarm (51), a switch sheet (52) is installed on the inside of the alarm (51), an alarm pointer device (6) is installed on the outer surface of the mounting column (4), the alarm pointer device (6) comprises a connecting sheet (61), the connecting sheet (61) is engaged with the switch sheet (52), the top surface of the connecting sheet (61) is detachably connected to a connecting rod (62), and the top of the connecting rod (62) is fixedly connected to a pointer plate (63).

3. A transformer winding temperature measuring device capable of temperature self-compensation according to claim 2, characterized in that: A plurality of alarm devices (5) are fixedly connected to the top surface of the mounting plate (42), a plurality of alarm pointer devices (6) are installed on the outer side of the mounting column (4), and a through slot (64) is formed on the surface of a portion of the connecting piece (61).

4. A transformer winding temperature measuring device capable of temperature self-compensation according to claim 3, characterized in that: The front end of the switch sheet (52) is rotatably connected to a rubber wheel (7), the connection sheet (61) is configured to be arc-shaped, and a limiting column (71) is installed on the outside of the switch sheet (52).

5. The transformer winding temperature measuring device capable of temperature self-compensation according to claim 1, characterized in that: A shunt head (8) is installed at the connection between the capillary tube (14) and the Bourdon spring (13), a first shunt tube (81) is fixedly connected to the outside of the shunt head (8), and a cavity (82) is fixedly connected to the end of the first shunt tube (81).

6. A transformer winding temperature measuring device capable of temperature self-compensation according to claim 5, characterized in that: A gear ring (83) is installed on the outside of the Bourdon spring (13), a rack (84) is slidably connected to the inner wall of the top space (11), the rack (84) is engaged with the gear ring (83), a slide slot bin (85) is installed at the end of the rack (84), and a second shunt pipe (86) is arranged on the outside of the slide slot bin (85).

7. The transformer winding temperature measuring device capable of temperature self-compensation according to claim 1, characterized in that: The top surface and the bottom surface of the driving wheel (12) are both rotatably connected to a plurality of rollers (9).

8. A method for using a transformer winding temperature measuring device capable of temperature self-compensation, characterized in that: A transformer winding temperature measuring device capable of temperature self-compensation for executing any one of claims 1 to 7, comprising the following steps: S1: The temperature sensing tube (24) is inserted into the oil hole of the transformer, and the mounting joint (3) is rotated to fix the position of the temperature sensing tube (24). The transformer is not loaded and the winding is not heated. According to the thermal expansion and contraction of the kerosene in the temperature sensing package (15), the Bourdon spring (13) drives the temperature pointer (18) to rotate, thereby measuring the top oil temperature of the transformer, which is recorded as the first measurement; S2: Transformer load, simulating the heating of the winding, the current sensor outputs a current proportional to the load, the current flows through the isolation tube (23) via the current matcher, the isolation tube (23) causes the temperature of the temperature-sensing package (15) to rise, and the displacement of the Bourdon spring (13) to expand, thereby measuring the sum of the transformer top oil temperature and the winding temperature, which is recorded as the second measurement; S3: At the same time, the Pt100 probe (22) also measures the transformer top oil temperature or the sum of the transformer top oil temperature and the winding temperature when the transformer is loaded or not, which is recorded as the third measurement and the fourth measurement; S4: The difference between the first and second measurements is the winding temperature. Similarly, the difference between the third and fourth measurements is also the winding temperature. Then the average value of the two sets of winding temperatures is calculated.

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