Experimental device for verifying simulation calculation of two-dimensional axisymmetric temperature field of transformer winding

Abstract

The utility model relates to an experimental device for verifying simulation calculation of a two-dimensional axisymmetric temperature field of a transformer winding, and belongs to the field of power transformer application. According to the technical scheme, a power supply device is connected with a circular winding (2), a thermocouple is arranged in the circular winding (2), and a temperature rise measuring device (3) is connected with the thermocouple; the round winding (2) is formed by winding a single flat copper wire into a wire turn, the wire turn is continuously wound in the radial direction of the wire turn to form a wire cake (204), and a plurality of wire cakes (204) are arranged in the axial direction to form a cake type winding. The device has the beneficial effects that the cooling effect of the circular transformer winding in a natural cooling mode can be realized, the temperature rise distribution of the circular transformer winding can be measured in a laboratory, and the device is used for verifying and determining the relationship between the temperature rise of the circular transformer winding in the natural cooling mode and software simulation parameters; and a foundation is laid for simplifying simulation modeling and rapid simulation calculation of the circular transformer winding.

Description

Technical Field

[0001] The utility model relates to an experimental device for verifying simulation calculation of two-dimensional axisymmetric temperature field of transformer windings, and belongs to the application field of power transformers. Background Art

[0002] Transformers are crucial energy transmission equipment in power systems, and their proper operation is crucial to their stability. Excessive temperature rise can cause aging and damage to the transformer's insulation, reducing operational reliability and potentially even causing serious accidents such as fires. Transformer windings are key components of power transformers. Statistics show that 60%-70% of power transformer failures are caused by the windings. Excessively high hotspot temperatures in transformer windings accelerate insulation aging and shorten transformer life; excessively low hotspot temperatures underutilize the transformer's capacity, reducing economic efficiency. However, determining the location and magnitude of hotspot temperature rises in power transformer windings is difficult. Existing technologies use computer simulation methods to comprehensively understand the distribution of the winding temperature field. Three-dimensional transformer winding field simulation considers all three dimensions, providing more accurate spatial information. However, this model is more complex and requires more computing resources and time. To simplify calculations and improve efficiency, two-dimensional axisymmetric fields are often used in engineering to simulate transformer windings. However, simulation calculations require the setting and input of numerous parameters and mathematical models to ensure that the temperature distribution and hotspot location of the transformer windings are consistent with the experiment. Existing technologies do not have an experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of the transformer windings. Therefore, it is of great significance to carry out research on a device for verifying the temperature field of the power transformer windings. Utility Model Content

[0003] The purpose of the utility model is to provide an experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of the transformer winding, which can realize the cooling effect of the transformer winding under the natural cooling mode, and can measure the temperature rise distribution of the transformer winding. It is used to verify and determine the relationship between the winding loss, temperature rise and software simulation parameters of the two-dimensional axisymmetric field simulation model of the transformer winding under different working conditions, and solve the above-mentioned problems existing in the background technology.

[0004] The technical solution of the utility model is:

[0005] The invention discloses an experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of a transformer winding, comprising a power supply device, a circular winding, a thermocouple and a temperature rise measuring device, wherein the power supply device is connected to the circular winding, the thermocouple is arranged in the circular winding, and the temperature rise measuring device is connected to the thermocouple; the circular winding is wound into turns by a single flat copper wire, and the turns are continuously wound along its radial direction to form a coil, and multiple coils are arranged along the axial direction to form a pancake winding, that is, a circular winding, and there are no joints between adjacent coils, and the wires are output from the ends; the circular winding is provided with end rings, inner support bars, outer support bars, pads, inner screens, outer screens, inner axial air ducts, outer axial air ducts and radial air ducts; end rings are respectively provided at the uppermost and lowermost ends of the coil, radial air ducts are provided between adjacent coils, inner axial air ducts and outer axial air ducts are respectively provided on both sides of the coil, and inner screens and outer screens are respectively provided outside the inner axial air duct and the outer axial air duct; outer support bars are provided between the coil and the outer screen, and inner support bars are provided between the coil and the inner screen.

[0006] The upper and lower ends of the inner axial air duct at the end ring position are the air inlet and air outlet of the inner axial air duct respectively; the upper and lower ends of the outer axial air duct at the end ring position are the air inlet and air outlet of the outer axial air duct respectively.

[0007] The thermocouple includes an axial thermocouple and a radial thermocouple. The axial thermocouple is installed in the upper pancake winding of the circular winding and is evenly arranged in the axial direction. The axial thermocouple measures the axial temperature distribution of the pancake winding; the radial thermocouple is installed at the same radial position inside the wire pancake. Multiple radial thermocouples on the same wire pancake are arranged every other turn. Multiple radial thermocouples are evenly arranged in the circumferential direction on the circular winding; the radial thermocouple measures the radial temperature distribution of the pancake winding.

[0008] The circular winding is placed on a support.

[0009] Pads are provided between the wire cake and the inner and outer screens.

[0010] The power supply device includes a voltage regulator, which supplies power to the circular winding. By adjusting the voltage, the voltage regulator provides different experimental operating conditions for the circular winding. The bracket supports the circular winding at a certain height from the bottom surface, preventing the influence of metal objects such as bottom steel bars on the circular winding's leakage magnetic field. The thermocouple is a well-known and commonly used temperature measuring element.

[0011] The beneficial effects of the utility model are: it can realize the cooling effect of the circular transformer winding under the natural cooling mode, can measure the temperature rise distribution of the circular transformer winding, can be carried out in the laboratory, has low cost, and can realize the research requirements of testing at any time, repeated experiments and repeated verification. It is used to verify and determine the relationship between the temperature rise of the circular transformer winding under the natural cooling mode and the software simulation parameters, and lays the foundation for simplifying the simulation modeling of the circular transformer winding and rapid simulation calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a block diagram of an embodiment of the utility model;

[0013] Figure 2 It is a two-dimensional axisymmetric diagram of a circular winding according to an embodiment of the present utility model;

[0014] Figure 3 This is a top view of a circular winding according to an embodiment of the present utility model;

[0015] In the figure: voltage regulator 1; circular winding 2; temperature rise measuring device 3; bracket 4; outer screen 201; outer axial air duct 202; outer support bar 203; coil 204; inner support bar 205; inner axial air duct 206; inner screen 207;

[0016] Radial air duct 208; end ring 209; axial thermocouple Z; radial thermocouple F. DETAILED DESCRIPTION

[0017] The present invention will be further described below with reference to the accompanying drawings and examples.

[0018] An experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of a transformer winding comprises a power supply device, a circular winding 2, a thermocouple and a temperature rise measuring device 3. The power supply device is connected to the circular winding 2, the thermocouple is arranged in the circular winding 2, and the temperature rise measuring device 3 is connected to the thermocouple; the circular winding 2 is wound into turns by a single flat copper wire, and the turns are continuously wound along its radial direction to form a coil 204. A plurality of coils 204 are arranged axially to form a pancake winding, i.e., a circular winding 2. There are no joints between adjacent coils 204, and the wires are output at the end; the circular winding 2 is provided with an end ring 209, an inner support bar 205, and an outer support bar. 203, a pad, an inner screen 207, an outer screen 201, an inner axial air duct 206, an outer axial air duct 202 and a radial air duct 208; end rings 209 are respectively provided at the uppermost and lowermost ends of the wire cake 204, a radial air duct 208 is provided between adjacent wire cakes 204, an inner axial air duct 206 and an outer axial air duct 202 are respectively provided on both sides of the wire cake 204, an inner screen 207 and an outer screen 201 are respectively provided outside the inner axial air duct 206 and the outer axial air duct 202; an outer support bar 203 is provided between the wire cake 204 and the outer screen 201, and an inner support bar 205 is provided between the wire cake 204 and the inner screen 207.

[0019] The upper and lower ends of the inner axial air duct 206 at the end ring 209 are the air inlet and air outlet of the inner axial air duct 206 respectively; the upper and lower ends of the outer axial air duct 202 at the end ring 209 are the air inlet and air outlet of the outer axial air duct 202 respectively.

[0020] The thermocouple includes an axial thermocouple Z and a radial thermocouple F. The axial thermocouple Z is installed in the upper pancake winding of the circular winding 2 and is evenly arranged in the axial direction. The axial thermocouple Z measures the axial temperature distribution of the pancake winding; the radial thermocouple F is installed in the same radial position inside the wire pancake 204. Multiple radial thermocouples F on the same wire pancake are arranged every other turn. Multiple radial thermocouples F are evenly arranged in the circumferential direction on the circular winding 2; the radial thermocouple F measures the radial temperature distribution of the pancake winding.

[0021] The circular winding 2 is placed on a support 4 .

[0022] Pads are provided between the wire coil 204 and the inner and outer screens 207 and 201 .

[0023] The power supply device is composed of a voltage regulator, a socket and a three-phase power supply. The voltage regulator supplies power to the circular winding and has the function of adjusting the voltage. Different experimental working conditions are provided to the circular winding by adjusting the voltage. The socket power supply is a fixed 220V power supply, which supplies power to the temperature rise measuring device. The bracket makes the circular winding a certain height away from the bottom surface, and is used to support the circular winding to avoid the influence of metal objects such as the bottom steel bars on the leakage magnetic field of the circular winding. The thermocouple is a temperature measurement sensor made based on the hot spot effect. It has a wide temperature measurement range and does not require an external power supply. It can convert the temperature signal into a thermoelectromotive force signal, which is converted into the temperature of the measured medium through the temperature rise measuring device. It is used to measure the conductor temperature and ambient temperature of the circular transformer winding by burying the copper-constantan thermocouple.

Claims

1. An experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of transformer windings, characterized by: The invention comprises a power supply device, a circular winding (2), a thermocouple and a temperature rise measuring device (3), wherein the power supply device is connected to the circular winding (2), the thermocouple is arranged in the circular winding (2), and the temperature rise measuring device (3) is connected to the thermocouple; the circular winding (2) is wound into turns by a single flat copper wire, the turns are continuously wound along the radial direction to form a wire cake (204), a plurality of wire cakes (204) are arranged along the axial direction to form a pancake-type winding, i.e., the circular winding (2), there is no joint between adjacent wire cakes (204), and the end wires are output; the circular winding (2) is provided with an end ring (209), an inner support bar (205), an outer support bar (203), a spacer, an inner screen (207), an outer screen (208), and a plurality of wire cakes (204) are arranged along the axial direction to form a pancake-type winding, i.e., the circular winding (2). 01), inner axial air duct (206), outer axial air duct (202) and radial air duct (208); end rings (209) are respectively provided at the uppermost and lowermost ends of the wire cake (204); radial air ducts (208) are provided between adjacent wire cakes (204); inner axial air duct (206) and outer axial air duct (202) are respectively provided on both sides of the wire cake (204); inner screen (207) and outer screen (201) are respectively provided outside the inner axial air duct (206) and the outer axial air duct (202); outer support bars (203) are provided between the wire cake (204) and the outer screen (201); inner support bars (205) are provided between the wire cake (204) and the inner screen (207).

2. The experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of transformer windings according to claim 1, characterized in that: The upper and lower ends of the inner axial air duct (206) at the position of the end ring (209) are respectively the air inlet and the air outlet of the inner axial air duct (206); the upper and lower ends of the outer axial air duct (202) at the position of the end ring (209) are respectively the air inlet and the air outlet of the outer axial air duct (202).

3. An experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of transformer windings according to claim 1 or 2, characterized in that: The thermocouple comprises an axial thermocouple (Z) and a radial thermocouple (F), wherein the axial thermocouple (Z) is installed in the upper pancake winding of the circular winding (2) and is evenly arranged in the axial direction; the radial thermocouple (F) is installed at the same radial position inside the wire pancake (204), and multiple radial thermocouples (F) on the same wire pancake are arranged in alternate turns, and the multiple radial thermocouples (F) are evenly arranged in the circumferential direction on the circular winding (2).

4. An experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of transformer windings according to claim 1 or 2, characterized in that: The circular winding (2) is placed on a bracket (4).

5. The experimental device for verifying the simulation calculation of the two-dimensional axisymmetric temperature field of transformer windings according to claim 1 or 2, characterized in that: The power supply device comprises a voltage regulator (1) which supplies power to the circular winding.

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