Temperature control device for converter transformer oil paper alternating current and direct current voltage composite test

Abstract

The invention relates to the technical field of converter transformers, and particularly discloses a temperature control device for a converter transformer oil paper alternating current and direct current voltage composite test, which comprises a temperature control box, a partition plate is arranged on the inner wall of the temperature control box to divide the internal space into a heating cavity and a regulation and control cavity, and a box door for taking and placing a test oil paper sample is arranged at the top end of the temperature control box; a silicon controlled rectifier power regulator is arranged in a regulation and control cavity of the temperature control box; the clamping assembly is mounted in the heating cavity; the heating assemblies are installed in the heating cavity and located on the two sides of the oiled paper sample, and the distance between the heating assemblies is adjustable; the driving assembly is mounted in the heating cavity; wherein the heating assembly is matched with the silicon controlled rectifier power regulator to construct a temperature gradient field through coarse adjustment of the total heating power. The device is provided with a controllable temperature field capable of simulating gradient change, the accuracy of subsequent experimental data is improved, and the device is provided with an elastic self-adaptive clamp.

Description

Technical Field

[0001] This invention relates to the field of converter transformer technology, and more specifically to a temperature control device for a combined AC / DC voltage test of converter transformer oil paper. Background Technology

[0002] As a core component of high-voltage direct current (HVDC) transmission systems, the reliability of the converter transformer's insulation performance directly determines the safe and stable operation of the entire system. The valve-side windings of the converter transformer simultaneously bear the combined voltage stress of AC voltage, DC voltage, and harmonics, making their operating conditions extremely harsh. Oil-paper insulation is the primary insulation form within the converter transformer, and its electrical properties, particularly dielectric strength, space charge accumulation and dissipation characteristics, and aging rate, are closely related to the temperature field distribution and temperature value of the insulation material. Therefore, conducting precise AC / DC composite voltage tests on oil-paper insulation samples in a laboratory environment, simulating actual operating temperature conditions, is crucial for evaluating and ensuring the insulation design of converter transformers.

[0003] Existing temperature control devices for AC / DC voltage composite tests of converter transformers generally employ integrated, large-scale constant temperature chambers or oil baths for heating. However, the load on converter transformers is dynamically changing, and the temperature of their insulation system also changes accordingly. This results in insufficient dynamic temperature control capability of the temperature control device, poor coordination with electrical stress, and inaccurate subsequent test data. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this invention provides a temperature control device for AC / DC voltage composite testing of converter transformer oil paper, which can solve the problems mentioned in the background art.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A temperature control device for AC / DC voltage composite testing of converter transformer oil paper includes:

[0007] A temperature control chamber, wherein the inner wall of the temperature control chamber is provided with a partition to divide the internal space into a heating chamber and a control chamber, the top of the temperature control chamber is provided with a door for taking out and putting in the test oil paper sample, and a silicon controlled rectifier is provided in the control chamber of the temperature control chamber;

[0008] Clamping assembly, installed in the heating chamber;

[0009] Heating components are installed in the heating chamber, located on both sides of the oil paper sample, with an adjustable spacing.

[0010] The drive assembly is installed in the heating chamber;

[0011] The clamping component holds an oil paper sample within a certain length range. The heating component, in conjunction with a silicon controlled rectifier (SCR) power regulator, constructs a temperature gradient field by coarsely adjusting the total heating power. This drives the component to adjust the distance between the heating component and the oil paper sample, thereby improving the precision of the temperature environment simulation.

[0012] Preferably, the temperature control box is provided with a control panel at the top that matches the control cavity, and the box door matches the heating cavity.

[0013] Preferably, the clamping assembly includes two support plates, which are fixedly installed on the bottom wall of the heating chamber. The top of the support plate is provided with multiple grooves, and two horizontal plates are installed in the grooves of the support plate. The top of the support plate is provided with multiple horizontal plates, and the top of the horizontal plates is provided with two elastic limiting members. The two elastic limiting members abut against each other and are suitable for accommodating the oil paper sample.

[0014] Preferably, the elastic limiting member is composed of an integrally formed first section and a second section, wherein the cross-section of the first section is a continuous wave shape, and the second section is a flat straight plate.

[0015] Preferably, the support plate has a vertical plate at its top, the two elastic limiting members are symmetrically arranged about the vertical plate, the vertical plate has a trapezoidal groove at its top, the trapezoidal groove of the vertical plate matches the oil paper sample, and tension springs are respectively provided between the two elastic limiting members and the vertical plate.

[0016] Preferably, the heating assembly includes multiple heat insulation boxes, and multiple limiting rods are provided between the opposing side walls of the heating chamber of the temperature control box. The heat insulation boxes are slidably installed between the multiple limiting rods. The multiple heat insulation boxes are grouped in pairs, and the openings of each group of heat insulation boxes are arranged facing each other and symmetrically with respect to the oil paper sample. A resistance heating wire is provided inside the heat insulation box, and the resistance heating wire is electrically connected to the thyristor power regulator. Multiple crossbars are provided between the multiple heat insulation boxes facing the same direction.

[0017] Preferably, the drive assembly includes two horizontal connecting plates, which are respectively installed on the bottom ends of two sets of multiple heat insulation boxes facing the same direction. A straight rack is provided at the bottom end of each of the two horizontal connecting plates. A support frame is provided on the bottom wall of the heating chamber of the temperature control box. A servo motor is provided on the top wall of the support frame. A gear is keyed to the output shaft of the servo motor. The gear is meshed with the straight rack.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. By setting up heating components and a thyristor power regulator, after the test program is started, the thyristor power regulator applies modulated power to each group of resistance heating wires according to the received control signal to simulate the radial temperature gradient of the insulation structure of the converter transformer during operation. When the test program requires simulating "load sudden change", the system can quickly instruct the drive component to act, finely adjust the distance between the heating component and the oil paper sample, and combine the power change of the thyristor power regulator to achieve rapid temperature response and the establishment of a new steady-state gradient field. Throughout the test, the temperature sensors arranged near the heating chamber and the oil paper sample feed back temperature data to the control system in real time, realizing the precise coupling test of the electro-thermal multi-stress field.

[0020] The beneficial effects are: it provides a controllable temperature field that can simulate gradient changes, thus improving the accuracy of subsequent experimental data.

[0021] 2. By setting up a clamping mechanism, the cut strip of oil paper sample is inserted between two elastic limiting members, and the bottom end is placed in the trapezoidal groove at the top of the upright plate. The two elastic limiting members can be used as a whole, and the compression of the tension spring behind them allows for a slight adaptive retraction, thereby providing a constant and gentle clamping force without damaging the sample.

[0022] The beneficial effects are: the elastic adaptive clamp reduces interference with the thermal field distribution of the sample itself.

[0023] 3. By setting up a temperature control chamber, the inner wall of the temperature control chamber is equipped with a partition to divide the internal space into a heating chamber and a control chamber. The top of the temperature control chamber is equipped with a door for taking out and putting in the test oil paper sample. The operator can easily put one end of the sample into the trapezoidal groove of the upright plate and smoothly guide the main body of the sample between the two elastic limiting members, which greatly reduces the difficulty of operation.

[0024] The beneficial effects are: it facilitates the positioning and installation of slender, soft strips of oil paper, thus improving the efficiency of test preparation. Attached Figure Description

[0025] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 This is a structural diagram of the partition and temperature control box in this invention;

[0028] Figure 3 This is a structural diagram of the heating assembly in this invention;

[0029] Figure 4 This is a diagram showing the installation structure of the servo motor and support frame in this invention;

[0030] Figure 5 This is an exploded view of the clamping assembly in this invention;

[0031] Figure 6 For the present invention Figure 5 Enlarged view of the structure at point A in the middle;

[0032] Figure 7 This is a diagram showing the installation structure of the gear and spur rack in this invention.

[0033] Explanation of reference numerals in the attached figures:

[0034] In the picture:

[0035] 1. Temperature control box; 2. Shelf; 3. Box door; 4. Thyristor power regulator;

[0036] 11. Support plate; 12. Horizontal plate; 13. Elastic limiting component; 14. Vertical plate; 15. Tension spring;

[0037] 21. Limiting rod; 22. Heat insulation box; 23. Resistance heating wire; 24. Horizontal connecting rod;

[0038] 31. Horizontal connecting plate; 32. Straight rack; 33. Support frame; 34. Servo motor; 35. Gear. Detailed Implementation

[0039] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the specific implementation methods, structures, features, and effects of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and preferred embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] In the description of this application, it should be understood that the orientation or positional relationship indicated by terms such as "inner" and "outer" are based on the orientation or position shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, a specific orientation structure and operation, and therefore should not be construed as a limitation of this application.

[0041] Reference Figures 1-7The present invention discloses a temperature control device for AC / DC voltage composite testing of converter transformer oil paper, comprising: a temperature control box 1, wherein a partition 2 is provided on the inner wall of the temperature control box 1 to divide the internal space into a heating chamber and a control chamber, a door 3 for taking out and placing test oil paper samples is provided at the top of the temperature control box 1, a control panel matching the control chamber is provided at the top of the temperature control box 1, the door 3 is matching the heating chamber, and a thyristor power regulator 4 is provided in the control chamber of the temperature control box 1.

[0042] In order to clamp an oil paper sample of a certain length, in this embodiment: a clamping assembly is installed in the heating chamber. The clamping assembly includes two support plates 11, which are fixedly installed on the bottom wall of the heating chamber. The top of the support plate 11 is provided with multiple grooves, and two horizontal plates 12 are installed in the grooves of the support plate 11. The top of the support plate 11 is provided with multiple horizontal plates 12, and the top of the horizontal plates 12 is provided with two elastic limiting members 13. The two elastic limiting members 13 abut against each other and are suitable for accommodating the oil paper sample. The elastic limiting member 13 is composed of an integrally formed first section and a second section. The first section has a continuous wavy cross section, and the second section is a flat straight plate. The top of the support plate 11 is provided with a vertical plate 14. The two elastic limiting members 13 are symmetrically arranged about the vertical plate 14. The top of the vertical plate 14 is provided with a trapezoidal groove, which matches the oil paper sample. Tension springs 15 are provided between the two elastic limiting members 13 and the vertical plate 14 respectively.

[0043] To construct a temperature gradient field, in this embodiment: a heating assembly is installed in the heating chamber, located on both sides of the oil paper sample with an adjustable spacing. The heating assembly includes multiple heat insulation boxes 22. Multiple limiting rods 21 are provided between the opposing side walls of the heating chamber of the temperature control box 1. The heat insulation boxes 22 are slidably installed between the multiple limiting rods 21. The multiple heat insulation boxes 22 are arranged in pairs, with the openings of each pair of heat insulation boxes 22 facing each other and symmetrically arranged with respect to the oil paper sample. A resistance heating wire 23 is provided inside the heat insulation box 22. The resistance heating wire 23 is electrically connected to the thyristor power regulator 4. Multiple crossbars 24 are provided between the multiple heat insulation boxes 22 facing the same direction.

[0044] To adjust the distance between the heating component and the oil paper sample and improve the accuracy of temperature environment simulation, in this embodiment: a driving component is installed in the heating chamber. The driving component includes two horizontal connecting plates 31, which are respectively installed at the bottom of two sets of multiple heat insulation boxes 22 facing the same direction. A rack 32 is provided at the bottom of each of the two horizontal connecting plates 31. A support frame 33 is provided on the bottom wall of the heating chamber of the temperature control box 1. A servo motor 34 is provided on the top wall of the support frame 33. A gear 35 is keyed to the output shaft of the servo motor 34. The gear 35 is meshed with the rack 32.

[0045] The working principle of this invention is as follows: A symmetrical heating system with adjustable distance and power creates a controllable temperature field that can simulate gradient changes on both sides of the oil paper sample; an elastic adaptive clamping mechanism is used to clamp the oil paper sample within a certain length range, which, while fixing samples of different thicknesses, minimizes interference with the thermal field distribution of the sample itself, and works in conjunction with the heating system to achieve precise control of the oil paper temperature throughout the test section.

[0046] Operating Procedure: First, the operator starts the system power supply via the control panel, initializes each electrical unit, opens the door 3 to expose the heating chamber, and inserts the cut strip of oil paper sample between the two elastic limiting members 13, with the bottom end placed in the trapezoidal groove at the top of the upright plate 14. The two elastic limiting members 13 can act as a whole, and by compressing the tension spring 15 behind them, they can perform a slight adaptive retraction, thereby providing a constant and gentle clamping force without damaging the sample. Next, adjust the spacing between the heating units: According to the width of the oil paper sample used in this experiment and the target temperature field requirements, input the command via the control panel. After receiving the signal, the servo motor 34 rotates, driving the gear 35 to rotate, which in turn drives the two straight racks 32 meshing with the gear 35 to move in opposite directions. The straight racks 32 drive the horizontal connecting plate 31, the heat insulation box 22, and the resistance heating wire 23 fixed above them to slide synchronously along the limiting rod 21 until the heating components on both sides reach the preset position. Positioning: This step ensures optimal radiative and convective heat transfer distance between the heating source and the sample. Next, close chamber door 3 to ensure the heating chamber is sealed, reducing internal heat loss and environmental interference. After the test program starts, the thyristor power regulator 4 applies precisely modulated power to each group of resistance heating wires 23 according to the received control signal, simulating the radial temperature gradient of the insulation structure during converter transformer operation. Throughout the test, temperature sensors placed near the heating chamber and the oil paper sample provide real-time temperature data feedback to the control system. When the test program requires simulating "load sudden change", the system can quickly instruct the drive components to act, finely adjust the distance between the heating components and the oil paper sample, and combine the power change of the thyristor power regulator 4 to achieve rapid temperature response and the establishment of a new steady-state gradient field. This process is synchronized with the application of electrical stress by the external AC / DC voltage composite test device, realizing a precise coupling test of the electro-thermal multi-stress field.

[0047] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A temperature control device for combined AC / DC voltage testing of converter transformer oil paper, characterized in that, include: Temperature control box (1), the inner wall of the temperature control box (1) is provided with a partition (2) to divide the internal space into a heating chamber and a control chamber. The top of the temperature control box (1) is provided with a door (3) for taking out and putting in the test oil paper sample. The control chamber of the temperature control box (1) is provided with a thyristor power regulator (4). Clamping assembly, installed in the heating chamber; Heating components are installed in the heating chamber, located on both sides of the oil paper sample, with an adjustable spacing. The drive assembly is installed in the heating chamber; The clamping component clamps an oil paper sample of a certain length range. The heating component, in conjunction with the thyristor power regulator (4), constructs a temperature gradient field by coarsely adjusting the total heating power, and drives the component to adjust the distance between the heating component and the oil paper sample, thereby improving the precision of the temperature environment simulation.

2. The temperature control device for AC / DC voltage composite testing of converter transformer oil paper according to claim 1, characterized in that, The temperature control box (1) is equipped with a control panel that matches the control cavity at the top, and the box door (3) matches the heating cavity.

3. The temperature control device for AC / DC voltage composite testing of converter transformer oil paper according to claim 1, characterized in that, The clamping assembly includes two support plates (11), which are fixedly installed on the bottom wall of the heating chamber. The top of the support plate (11) is provided with multiple grooves. Two horizontal plates (12) are installed in the grooves of the support plate (11). The top of the support plate (11) is provided with multiple horizontal plates (12). The top of the horizontal plates (12) is provided with two elastic limiting members (13). The two elastic limiting members (13) abut against each other and are suitable for accommodating the oil paper sample.

4. The temperature control device for AC / DC voltage composite testing of converter transformer oil paper according to claim 3, characterized in that, The elastic limiting member (13) is composed of an integrally formed first section and a second section, wherein the cross-section of the first section is a continuous wave shape, and the second section is a flat straight plate.

5. The temperature control device for AC / DC voltage composite testing of converter transformer oil paper according to claim 3, characterized in that, The support plate (11) has a vertical plate (14) at its top. The two elastic limiting members (13) are symmetrically arranged about the vertical plate (14). The vertical plate (14) has a trapezoidal groove at its top. The trapezoidal groove of the vertical plate (14) matches the oil paper sample. The two elastic limiting members (13) are respectively provided with tension springs (15) between them and the vertical plate (14).

6. The temperature control device for AC / DC voltage composite testing of converter transformer oil paper according to claim 1, characterized in that, The heating assembly includes multiple heat insulation boxes (22). Multiple limiting rods (21) are provided between the opposite side walls of the heating chamber of the temperature control box (1). The heat insulation boxes (22) are slidably installed between the multiple limiting rods (21). The multiple heat insulation boxes (22) are arranged in pairs. The openings of each pair of heat insulation boxes (22) are arranged facing each other and symmetrically with respect to the oil paper sample. A resistance heating wire (23) is provided inside the heat insulation box (22). The resistance heating wire (23) is electrically connected to the thyristor power regulator (4). Multiple cross rods (24) are provided between the multiple heat insulation boxes (22) facing the same direction.

7. The temperature control device for AC / DC voltage composite testing of converter transformer oil paper according to claim 6, characterized in that, The drive assembly includes two horizontal connecting plates (31), which are respectively installed at the bottom of two sets of multiple heat insulation boxes (22) facing the same direction. The bottom of the two horizontal connecting plates (31) is respectively provided with a rack (32). The bottom wall of the heating chamber of the temperature control box (1) is provided with a support frame (33), and the top wall of the support frame (33) is provided with a servo motor (34). The output shaft of the servo motor (34) is keyed with a gear (35), and the gear (35) is meshed with the rack (32).

Images