A wind and rain load test device and method for a power transmission line

Abstract

The application discloses a kind of transmission line wind and rain load test device and method, including wind tunnel, the inside of the wind tunnel is provided with line simulation unit and rainfall simulation unit, the outside of the wind tunnel is provided with strong wind simulation unit and control unit;The line simulation unit includes suspension unit, and sensor unit and telescopic steel plate connected with the suspension unit;The rainfall simulation unit includes rain shower, and first servo motor connected with the rain shower;The strong wind simulation unit includes air duct, and fan arranged in the air duct;The control unit includes main control unit, and signal receiving unit connected with the main control unit.The application provides the simulation wind and rain load test conversion method and intelligent test device for 110kV transmission line, not only make the accuracy of simulation test higher, simultaneously, the simultaneous control of field and remote can also be realized, further improve the automation degree of test device.

Description

Technical Field

[0001] This invention relates to the field of power transmission line simulation technology, and in particular to a wind and rain load testing device and method for simulating insulator conductor systems of 110kV and above power transmission lines. Background Technology

[0002] In urban power distribution networks, overhead conductor insulation has achieved widespread coverage and is currently a commonly used insulation protection measure. Overhead insulated conductors are primarily supported by insulators made of porcelain or composite materials on distribution towers to achieve electrical insulation. However, transmission lines exposed to the atmosphere are highly susceptible to natural disasters such as strong winds and heavy rains. The combined effect of strong wind and rain loads can lead to transmission line breaks and tower collapses. Furthermore, strong winds and heavy rains are characterized by randomness, uncertainty, and seasonality, thus increasing the difficulty of defense against them. Currently, there is considerable research on the impact of wind and rain loads on transmission lines, but relatively little research on the combined effect of wind and rain loads. Although wind and rain simulation devices exist, the existing simulation devices have low levels of digitization and automation, and cannot perform wind and rain load simulations for the insulator-conductor system of 110kV overhead transmission lines. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a wind and rain load testing device and method for simulating the insulator-conductor system of 110kV and above transmission lines. By providing a method for calculating the wind and rain loads of suspension insulators-conductors in 110kV and above transmission lines, combined with a corresponding wind and rain simulation device, the wind and rain load testing device of this invention can achieve digital and highly automated simulation testing, thereby improving the accuracy and intelligence of simulation testing of 110kV and above transmission lines.

[0004] In a first aspect, embodiments of the present invention provide a power transmission line wind and rain load testing device, comprising:

[0005] The wind tunnel is equipped with a line simulation unit and a rainfall simulation unit inside, and a strong wind simulation unit and a control unit outside the wind tunnel.

[0006] The line simulation unit includes a suspension unit, a sensor unit connected to the suspension unit, and a retractable steel plate;

[0007] The rainfall simulation unit includes a rain shower and a first servo motor connected to the rain shower;

[0008] The strong wind simulation unit includes an air duct and a fan installed inside the air duct;

[0009] The control unit includes a main control unit and a signal receiving unit connected to the main control unit;

[0010] The main control unit is connected to the suspension unit, the retractable steel plate, the first servo motor and the fan respectively, and the signal receiving unit is connected to the sensor unit.

[0011] Furthermore, the suspension unit includes a hanging rod, a first spherical rotary joint, a telescopic rod, and a second spherical rotary joint connected in sequence;

[0012] The sensor unit includes a tension sensor and an angle sensor;

[0013] The tension sensor is provided between the hanging rod and the first spherical rotary joint, the angle sensor is provided between the first spherical rotary joint and the telescopic rod, and the second spherical rotary joint is connected to the telescopic steel plate.

[0014] Furthermore, a servo motor is provided on the first spherical rotary joint, the telescopic rod, the second spherical rotary joint, and the telescopic steel plate, namely the second servo motor, the third servo motor, the fourth servo motor, and the fifth servo motor, respectively;

[0015] The second servo motor, the third servo motor, the fourth servo motor, and the fifth servo motor are respectively connected to the main control unit.

[0016] Furthermore, the device also includes a scanning unit, which includes a first laser scanning unit and a second laser scanning unit;

[0017] The first laser scanning unit is mounted on the air duct and is located on the same horizontal line as the retractable steel plate, and is used to measure the horizontal scanning area of ​​the retractable steel plate.

[0018] The second laser scanning unit is located at the top of the wind tunnel and directly above the retractable steel plate, and is used to measure the ground projection area of ​​the retractable steel plate.

[0019] The first laser scanning unit and the second laser scanning unit are respectively connected to the signal receiving unit.

[0020] Furthermore, the rain shower is located at the top of the wind tunnel and above the hanging rod, and the air duct is located at the entrance of the wind tunnel.

[0021] Furthermore, the control unit also includes an internal console, a communication unit, an external server, and a remote console;

[0022] The internal control console is connected to the main control unit, the main control unit is connected to the external server through the communication unit, and the external server is connected to the remote control console.

[0023] Secondly, embodiments of the present invention provide a method for testing the wind and rain load on transmission lines, including:

[0024] The design parameters of the insulator conductor system of the three-tower two-span transmission line are obtained, and the load test data are calculated. The load test data includes the total weight, equivalent wind-receiving area, equivalent rain-receiving area, wind load per unit area, and rain load per unit area of ​​the insulator conductor system of the three-tower two-span transmission line.

[0025] The weight of the retractable steel plate is set as the total weight. The main control unit controls the expansion area of ​​the retractable steel plate, the air volume of the air duct, and the rainfall of the rain shower to conduct a wind and rain load test. The expansion area of ​​the retractable steel plate is a proportional simulation of the equivalent wind-receiving area and the equivalent rainfall-receiving area. The air volume of the air duct is the air volume corresponding to the equivalent wind load. The rainfall of the rain shower is the rainfall corresponding to the equivalent rain load. The equivalent wind load and the equivalent rain load are calculated using the expansion area of ​​the retractable steel plate, the wind load per unit area, and the rain load per unit area.

[0026] The tensile force and offset angle data of the expandable steel plate during the wind and rain load test are measured by the sensor unit, and the tensile force data and offset angle data are transmitted to the main control unit through the signal receiving unit.

[0027] Furthermore, the steps of obtaining the design parameters of the transmission line and calculating the load test data of the transmission line include:

[0028] The design parameters of the insulator conductor system for a three-tower, two-span transmission line are obtained. The design parameters include the design parameters of the lines on both sides of the suspension insulator and the design parameters of the suspension insulator itself. The design parameters of the lines on both sides of the suspension insulator include the horizontal span, elevation difference, vertical load ratio, horizontal stress, and line radius of the lines on both sides. The design parameters of the suspension insulator include the weight, length, and shed diameter of the suspension insulator.

[0029] Based on the design parameters of the suspension insulator, the wind-receiving area of ​​the insulator is calculated, and based on the design parameters of the lines on both sides of the suspension insulator, the wind-receiving area of ​​the transmission line, the rainfall-receiving area of ​​the transmission line, and the weight of the transmission line conductor are calculated.

[0030] Based on the wind-receiving area of ​​the insulator and the wind-receiving area of ​​the transmission line, the equivalent wind-receiving area of ​​the insulator-conductor system of the three-tower two-span transmission line is calculated, and the rainfall-receiving area of ​​the transmission line is taken as the equivalent rainfall-receiving area of ​​the insulator-conductor system of the three-tower two-span transmission line.

[0031] The total weight of the insulator and conductor system of the three-tower two-span transmission line is calculated based on the weight of the suspension insulator and the weight of the transmission line conductor.

[0032] Based on the preset wind speed and rainfall intensity, calculate the wind load and rain load of the insulator conductor system of the three-tower two-span transmission line;

[0033] Based on the wind load, the rain load, the equivalent wind-receiving area, and the equivalent rain-receiving area, the wind load per unit area and the rain load per unit area are calculated.

[0034] Furthermore, the steps of conducting the wind and rain load test by controlling the expansion area of ​​the expandable steel plate, the air volume of the air duct, and the rainfall of the rain shower through the main control unit include:

[0035] The weight of the expandable steel plate is set as the total weight of the insulator conductor system of the three-tower two-span transmission line.

[0036] The main control unit controls the tilt angle and horizontal position of the suspension unit so that the retractable steel plate and the first laser scanning unit are on the same horizontal line, and the retractable steel plate is located directly below the second laser scanning unit.

[0037] The retractable steel plate is scanned by the first laser scanning unit and the second laser scanning unit to obtain the horizontal scanning area and the ground projection area, respectively.

[0038] The ratio between the horizontal scan area and the ground projection area is taken as the first ratio, and the ratio between the equivalent wind-receiving area and the equivalent rainfall-receiving area is taken as the second ratio.

[0039] The main control unit controls the expansion and contraction area of ​​the expandable steel plate to make the first ratio equal to the second ratio.

[0040] The equivalent wind load of the retractable steel plate is calculated based on the wind load per unit area and the horizontal scanning area, and the equivalent rain load of the retractable steel plate is calculated based on the rain load per unit area and the ground projection area.

[0041] The main control unit controls the power of the fan so that the air volume of the duct is the same as the air volume corresponding to the equivalent wind load.

[0042] The main control unit controls the first servo motor so that the rainfall from the rain shower is equal to the rainfall corresponding to the equivalent rain load.

[0043] Furthermore, the wind-receiving area of ​​the insulator is calculated using the following formula:

[0044] S A =k*D*l

[0045] In the formula, S A denoted as the wind-receiving area of ​​the insulator, k is the equivalent area coefficient of the insulator, D is the diameter of the shed of the suspension insulator, and l is the length of the suspension insulator.

[0046] The wind-receiving area of ​​the transmission line is calculated using the following formula:

[0047]

[0048] In the formula, S B denoted as the windward area of ​​the transmission line, k1 as the equivalent area coefficient of the line, a as the line radius, θ as the wind direction angle, b1 and b2 as the horizontal span between the two spans of the line, c1 and c2 as the elevation difference between the two spans of the line, γ as the vertical load ratio, and σ as the horizontal stress.

[0049] The equivalent wind-receiving area is calculated using the following formula:

[0050] S1 = S A +S B

[0051] The equivalent rainfall-receiving area is calculated using the following formula:

[0052]

[0053] In the formula, β is the angle of rainfall;

[0054] The weight of the transmission line conductors is calculated using the following formula:

[0055]

[0056] The total weight of the insulator conductor system for the three-tower, two-span transmission line is calculated using the following formula:

[0057] G = G j +G1

[0058] In the formula, G j The weight of the suspension insulator;

[0059] The wind load per unit area is calculated using the following formula:

[0060]

[0061] In the formula, F1 is the wind load of the insulator conductor system of the three-tower two-span transmission line;

[0062] The unit area rain load is calculated using the following formula:

[0063]

[0064] In the formula, F2 is the rain load of the insulator conductor system of the three-tower two-span transmission line;

[0065] The equivalent wind load is calculated using the following formula:

[0066] F3=w1*S 1c

[0067] In the formula, S 1c The horizontal scan area;

[0068] The equivalent rain load is calculated using the following formula:

[0069] F4 = w2 * S 2c

[0070] In the formula, S 2c This represents the projected area of ​​the ground.

[0071] This invention provides a wind and rain load testing device and method for transmission lines. Addressing the limitations of existing wind and rain simulation devices for simulating insulator-conductor systems of 110kV and above transmission lines, and the lack of methods for calculating wind and rain loads in such systems, this invention provides a highly digitized and automated wind and rain simulation device. Based on this device, a method for calculating wind and rain loads is provided. This not only solves the problem of existing technologies being unable to achieve remote control without human supervision, allowing tests to be conducted simultaneously on-site and remotely, but also improves the simulation accuracy and intelligence of the device. Attached Figure Description

[0072] Figure 1 This is a schematic diagram of the structure of the power transmission line wind and rain load test device proposed in the embodiments of the present invention;

[0073] Figure 2 This is a schematic flowchart of the wind and rain load test method for transmission lines proposed in this embodiment of the invention. Detailed Implementation

[0074] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. 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.

[0075] Please see Figure 1 The first embodiment of the present invention proposes a transmission line wind and rain load test device, comprising: a wind tunnel 100, a line simulation unit and a rainfall simulation unit arranged inside the wind tunnel 100, and a strong wind simulation unit and a control unit 11 arranged outside the wind tunnel 100. The line simulation unit includes a suspension unit, a sensor unit connected to the suspension unit and a telescopic steel plate 6. The rainfall simulation unit includes a rain shower 10 and a first servo motor (not shown) connected to the rain shower. The strong wind simulation unit includes a wind duct 8 and a fan (not shown) installed inside the wind duct. The control unit 11 includes a main control unit 111 and a signal receiving unit 112. The functions of each unit in the test device and the relationship between each structure are described in detail below.

[0076] The line simulation unit in this embodiment is a line simulation of the insulator-conductor system of 110kV and above transmission lines. The line simulation unit is installed inside the wind tunnel 100 and mainly includes a suspension unit, a sensor unit and a telescopic steel plate 6. The suspension unit includes a hanging rod 1, a first spherical rotary joint 3, a telescopic rod 5 and a second spherical rotary joint 3. The sensor unit includes a tension sensor 2 and an angle sensor 4.

[0077] In the line simulation unit, the hanging rod 1 serves a fixing function and can be suspended below the hook. The tension sensor 2 is installed below the hanging rod 1 to measure the tension exerted by the entire device on the hanging rod 1. The first spherical rotary joint 3 connects the tension sensor 2 and the angle sensor 4, enabling 360-degree rotation to control the tilt angle and direction of the line simulation unit. The angle sensor 4 measures the deflection angle of the device under wind and rain loads. The telescopic rod 5 is connected to the telescopic steel plate 6 via the second spherical rotary joint 3. The telescopic rod 5 can control the horizontal position of the connected telescopic steel plate 6 by its extension length, and, in conjunction with the second spherical rotary joint 3, control the facing angle of the telescopic steel plate 6. The telescopic steel plate 6 can be extended and retracted to obtain the desired telescopic area. In the circuit simulation unit, the rotation and extension of each structure are achieved by electric drive. Specifically, a second servo motor, a third servo motor, a fourth servo motor, and a fifth servo motor are respectively installed on the first spherical rotary joint, the telescopic rod, the second spherical rotary joint, and the telescopic steel plate. These servo motors are all controlled by the main control unit 111 in the control unit 11.

[0078] In this embodiment, the first servo motor in the rainfall simulation unit is also controlled by the main control unit 111. That is, the rainfall of the rain shower 10 is controlled by controlling the first servo motor. The rain shower 10 is installed above the wind tunnel 100 and above the hanging rod 1. Its feature is that it provides all-round rainfall and the amount of rainfall can be adjusted by electric drive.

[0079] The strong wind simulation unit is installed outside the wind tunnel 100, with its air duct 8 facing the passage of the wind tunnel 100. A fan is installed inside the air duct 8, and the main control unit 111 controls the fan to adjust the wind speed, thereby controlling the air volume of the air duct 8.

[0080] The control unit 11 mainly includes a main control unit 111 and a signal receiving unit 112. The main control unit 111 can be a main control MCU to control the power drive in this device, while the signal receiving unit 112 can receive the sensor signal values ​​sent by the sensor unit and transmit them to the main control unit 111 for storage and processing.

[0081] This embodiment mainly achieves the simulation test of the transmission line by controlling the expansion area and position angle of the retractable steel plate 6, combined with rainfall simulation and strong wind simulation. Therefore, in order to achieve more accurate control of the retractable steel plate 6, a scanning unit is preferably set in this embodiment. The scanning unit includes a first laser scanning unit 7 and a second laser scanning unit 9. The first laser scanning unit 7 is set on the wind duct 8, and the second laser scanning unit 9 is set on the top of the wind tunnel 100. By adjusting the suspension device and the expansion area of ​​the retractable steel plate, the first laser scanning unit 7 can obtain the area directly facing the retractable steel plate 6 in real time, while the second laser scanning unit 9 can obtain the area projected onto the ground by the retractable steel plate 6 in real time. The scanning signals of the scanning units are transmitted to the main control unit 111 through the signal receiving unit 112.

[0082] To enable simultaneous on-site and remote control of the testing device, this embodiment preferably employs two types of control consoles: an internal console and a remote console. The internal console is connected to the main control unit 111, transmitting on-site personnel's operating commands to the main control unit 111 for device control. The external console is located remotely. The control unit 11 also includes a communication unit, and an external server is externally located. The communication unit connects to the external server and is linked to the remote console, allowing operation commands from the remote console to be uploaded to the external server and then transmitted to the main control unit 111 via the communication unit for remote control of the device. Simultaneously, angle and tensile force measurement data obtained during the experiment are uploaded to the external server via the communication unit and saved, while also being fed back to the remote console, thus achieving excellent human-machine interaction.

[0083] Please see Figure 2 Based on the same inventive concept, the second embodiment of the present invention provides a method for testing the wind and rain load of transmission lines. This method is applied to the above-mentioned testing apparatus and includes:

[0084] Step S10: Obtain the design parameters of the insulator conductor system of the three-tower two-span transmission line, and calculate the load test data. The load test data includes the total weight, equivalent wind-receiving area, equivalent rainfall-receiving area, wind load per unit area, and rain load per unit area of ​​the insulator conductor system of the three-tower two-span transmission line.

[0085] In existing technologies, there is no effective method for calculating wind and rain loads in simulation devices for insulator-conductor systems of 110kV and above transmission lines. Therefore, in conjunction with the aforementioned test device, this invention provides a method for calculating wind and rain loads of 110kV and above transmission lines. First, the design parameters of the transmission line are obtained. Due to the long length and large size of the transmission line, the insulator-conductor system of 110kV and above "three-tower two-span" transmission lines is selected as the object. The parameters of the insulator and conductor in this system are obtained, specifically including the horizontal span distances b1 and b2 of the two spans before and after the suspension insulator, the height differences c1 and c2 of the two spans before and after, the vertical load ratio γ, the horizontal stress σ, the radius a of the transmission line, and the weight G of the suspension insulator. j , length l and skirt diameter D.

[0086] Since this invention is a simulation test of wind load and rain load, it is necessary to calculate the actual wind load and rain load on the actual line. Assuming the wind speed under the actual working conditions is v1 and the rain intensity is x, the wind load F1 and rain load F2 of the line can be obtained according to the conventional wind and rain load calculation formula. These two load values ​​can be calculated according to the conventional calculation formula in this field, and the calculation process will not be described in detail here.

[0087] Secondly, we need to calculate the equivalent wind-receiving area and equivalent rainfall-receiving area at different angles in this system. The equivalent wind-receiving area is the sum of the wind-receiving area of ​​the insulator and the wind-receiving area of ​​the transmission line. Since the suspension insulator is columnar, the force-receiving area S in each direction can be approximated. A They are the same and are constant values. The length l of the suspension insulator, the diameter D of the shed, and k are the equivalent area coefficient of the insulator, thus obtaining the wind-receiving area S of the insulator. A :

[0088] S A =k*D*l

[0089] The wind-receiving area of ​​a transmission line can be calculated from the line radius *a*, the span distances *b1* and *b2* between the two spans, the wind direction angle *θ*, the vertical load ratio *γ*, the height differences *c1* and *c2* between the two spans, and the horizontal stress *σ*, where *k1* is the equivalent area coefficient of the conductor. Therefore, the wind-receiving area *S* of the transmission line... B The calculation formula is:

[0090] S B =2*k1*a*cosθ*l v

[0091] In the formula, l v Let L be the vertical span of the line. Since the conductors of the transmission line conform to the equation of a horizontal parabola, the conductor length L can be approximated as:

[0092]

[0093] In practical engineering, the vertical span of a transmission line can be approximated as half the line length, that is:

[0094] l v =0.5*L

[0095] Therefore, the wind-receiving area S of the transmission line is obtained. B for:

[0096]

[0097] Since the equivalent wind-receiving area is the sum of the wind-receiving area of ​​the insulator and the wind-receiving area of ​​the transmission line, the equivalent wind-receiving area S1 is:

[0098] S1 = S A +S B

[0099]

[0100] The equivalent rainfall-receiving area can also be considered as the sum of the rainfall-receiving area of ​​the insulator and the rainfall-receiving area of ​​the transmission line. Since the area of ​​the insulator is small, it can be ignored in actual calculations. Therefore, only the rainfall-receiving area of ​​the transmission line needs to be calculated.

[0101] S2=2*k1*a*cosβ*l v

[0102] Where β is the angle of rainfall, derived from the formula The line length L can be converted to:

[0103]

[0104] Thus, the transformed rainfall-receiving area of ​​the transmission line, i.e., the equivalent rainfall-receiving area S2, is obtained:

[0105]

[0106] Based on the wind load, rain load, equivalent wind-receiving area, and equivalent rain-receiving area calculated above, we can obtain the wind load per unit area w1 and the rain load per unit area w2, that is:

[0107]

[0108]

[0109] Simultaneously, for subsequent simulation tests, it is also necessary to calculate the total weight of the insulator-conductor system of the three-tower, two-span transmission line, that is, the weight of the suspension insulators within the three-tower, two-span system and the weight of the conductors within the transmission line. Since the weight G of the suspension insulators...j Since the weight of the conductor G is known, we only need to calculate the weight of the conductor G. l The weight of the conductor can be calculated from its length, cross-sectional area, and vertical load ratio.

[0110] G l =0.5πa 2 γL

[0111] Substituting the above L expression, we get:

[0112]

[0113] Therefore, the total weight of the insulator conductor system for a three-tower, two-span transmission line can be obtained:

[0114] G = G j +G l

[0115] Step S20: Set the weight of the retractable steel plate to the total weight. Conduct a wind and rain load test by controlling the expansion area of ​​the retractable steel plate, the air volume of the air duct, and the rainfall of the rain shower through the main control unit. The expansion area of ​​the retractable steel plate is a proportional simulation of the equivalent wind-receiving area and the equivalent rain-receiving area. The air volume of the air duct is the air volume corresponding to the equivalent wind load. The rainfall of the rain shower is the rainfall corresponding to the equivalent rain load. The equivalent wind load and the equivalent rain load are calculated using the expansion area of ​​the retractable steel plate, the wind load per unit area, and the rain load per unit area.

[0116] After obtaining the above load test data, a simulation test can be conducted in the test device. First, we set the weight of the telescopic steel plate in the test device according to the total weight of the insulator conductor system of the three-tower two-span transmission line calculated. That is, we set the weight of the two to be the same. This is to make the simulation process closer to reality, thereby improving the accuracy of the test.

[0117] Then, the main control unit 111 controls each electric drive device, i.e., the servo motor, in the test device, thereby controlling the tilt angle and horizontal position of the suspension unit, and simultaneously controlling the telescopic area of ​​the telescopic steel plate. This ensures that the position, angle, and telescopic area of ​​the telescopic steel plate meet the predetermined requirements, so that the telescopic steel plate is on the same horizontal line as the first laser scanning unit and is located directly below the second laser scanning unit. This allows the first laser scanning unit to scan the telescopic steel plate and obtain the horizontal scanning area S directly opposite the steel plate. 1c The ground projection area S obtained by scanning the retractable steel plate with the second laser scanning unit. 2c It must meet the following requirements:

[0118]

[0119] Since the weight of the expandable steel plate is the same as the total weight of the test object, the wind load and rain load per unit area calculated above can be applied to the expandable steel plate as equivalent, thus obtaining the equivalent wind load F3 and equivalent rain load F4 applied to the expandable steel plate:

[0120] F3=w1*S 1c

[0121] F4 = w2 * S 2c

[0122] Then, the power of the fan in the strong wind simulation unit can be controlled by the main control unit 111 to make the air volume of the air duct 8 consistent with the air volume corresponding to the equivalent wind load. At the same time, the rainfall of the rain shower 10 can be made consistent with the rainfall corresponding to the equivalent rain load by controlling the first servo motor in the rainfall simulation unit. That is, the mode test of wind and rain load of 110kV transmission line is realized.

[0123] Step S30: The tensile force data and offset angle data of the expandable steel plate during the wind and rain load test are measured by the sensor unit, and the tensile force data and offset angle data are transmitted to the main control unit through the signal receiving unit.

[0124] During the simulation test, the signal receiving unit 112 can receive the tension data and angle data measured by the tension sensor 2 and the angle sensor 4, and transmit them to the main control unit 111. The main control unit 111 will upload these data to an external server and save them through the communication unit, and at the same time feed them back to the remote operating console, thereby realizing simultaneous test control on site and remotely.

[0125] The technical features and effects of the transmission line wind and rain load test method proposed in this embodiment of the invention are the same as those of the device proposed in this embodiment of the invention, and will not be repeated here. Each module in the above-mentioned transmission line wind and rain load test device can be implemented entirely or partially through software, hardware, or a combination thereof. Each module can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0126] In summary, this invention provides a testing device and method for wind and rain loads on power transmission lines. The testing device includes a wind tunnel, with a line simulation unit and a rainfall simulation unit inside the wind tunnel, and a strong wind simulation unit and a control unit outside the wind tunnel. The line simulation unit includes a suspension unit, a sensor unit connected to the suspension unit, and a retractable steel plate. The rainfall simulation unit includes a rain shower and a first servo motor connected to the rain shower. The strong wind simulation unit includes a wind duct and a fan installed inside the wind duct. The control unit includes a main control unit and a signal receiving unit connected to the main control unit. The main control unit is connected to the suspension unit, the retractable steel plate, the first servo motor, and the fan, respectively, and the signal receiving unit is connected to the sensor unit. This invention provides a simulated wind and rain load test device and corresponding method for insulator-conductor systems of 110kV and above transmission lines. It solves the problems of the lack of a conversion method for wind and rain loads of 110kV transmission lines in the prior art, as well as the low degree of digitization and automation of existing simulation devices. It provides a more intelligent test device, which not only makes the simulation test more accurate, but also enables simultaneous on-site and remote control, further improving the automation level of the test device.

[0127] The various embodiments in this specification are described in a progressive manner. For directly identical or similar parts of the embodiments, refer to each other. Each embodiment focuses on describing the differences from other embodiments. In particular, the method embodiments are basically similar to the device embodiments, so the description is relatively simple; relevant parts can be referred to the description of the device embodiments. It should be noted that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0128] The embodiments described above are merely preferred embodiments of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various improvements and substitutions without departing from the technical principles of this invention, and these improvements and substitutions should also be considered within the scope of protection of this application. Therefore, the scope of protection of this patent application should be determined by the scope of the claims.

Claims

1. A test device for wind and rain load on transmission lines, characterized in that, include: The wind tunnel is equipped with a line simulation unit and a rainfall simulation unit inside, and a strong wind simulation unit and a control unit outside. The line simulation unit includes a suspension unit, a sensor unit connected to the suspension unit, and a retractable steel plate; The rainfall simulation unit includes a rain shower and a first servo motor connected to the rain shower; The strong wind simulation unit includes an air duct and a fan installed inside the air duct; The control unit includes a main control unit and a signal receiving unit connected to the main control unit; The main control unit is connected to the suspension unit, the retractable steel plate, the first servo motor and the fan respectively, and the signal receiving unit is connected to the sensor unit; The device further includes a scanning unit, which includes a first laser scanning unit and a second laser scanning unit; The first laser scanning unit is mounted on the air duct and is located on the same horizontal line as the retractable steel plate, and is used to measure the horizontal scanning area of ​​the retractable steel plate; The second laser scanning unit is located at the top of the wind tunnel and directly above the retractable steel plate, and is used to measure the ground projection area of ​​the retractable steel plate. The first laser scanning unit and the second laser scanning unit are respectively connected to the signal receiving unit.

2. The transmission line wind and rain load testing device according to claim 1, characterized in that, The suspension unit includes a hanging rod, a first spherical rotary joint, a telescopic rod, and a second spherical rotary joint connected in sequence. The sensor unit includes a tension sensor and an angle sensor; The tension sensor is provided between the hanging rod and the first spherical rotary joint, the angle sensor is provided between the first spherical rotary joint and the telescopic rod, and the second spherical rotary joint is connected to the telescopic steel plate.

3. The transmission line wind and rain load testing device according to claim 2, characterized in that, Each of the first spherical rotary joint, the telescopic rod, the second spherical rotary joint, and the telescopic steel plate is equipped with a servo motor, namely the second servo motor, the third servo motor, the fourth servo motor, and the fifth servo motor; The second servo motor, the third servo motor, the fourth servo motor, and the fifth servo motor are respectively connected to the main control unit.

4. The transmission line wind and rain load testing device according to claim 2, characterized in that, The rain shower is installed at the top of the wind tunnel and above the hanging rod, and the air duct is installed at the entrance of the wind tunnel.

5. The transmission line wind and rain load testing device according to claim 1, characterized in that, The control unit also includes an internal console, a communication unit, an external server, and a remote console; The internal control console is connected to the main control unit, and the main control unit is connected to the external server through the communication unit. The external server is used to receive and store sensor data measured by the sensor unit transmitted by the communication unit, and the external server is connected to the remote control console.

6. A method for testing the wind and rain load of a transmission line, wherein the method is applied to the wind and rain load testing apparatus for transmission lines as described in any one of claims 1 to 5, characterized in that, include: The design parameters of the insulator conductor system of the three-tower two-span transmission line are obtained, and the load test data are calculated. The load test data includes the total weight, equivalent wind-receiving area, equivalent rain-receiving area, wind load per unit area, and rain load per unit area of ​​the insulator conductor system of the three-tower two-span transmission line. The weight of the retractable steel plate is set as the total weight. The main control unit controls the expansion area of ​​the retractable steel plate, the air volume of the air duct, and the rainfall of the rain shower to conduct a wind and rain load test. The expansion area of ​​the retractable steel plate is a proportional simulation of the equivalent wind-receiving area and the equivalent rainfall-receiving area. The air volume of the air duct is the air volume corresponding to the equivalent wind load. The rainfall of the rain shower is the rainfall corresponding to the equivalent rain load. The equivalent wind load and the equivalent rain load are calculated using the expansion area of ​​the retractable steel plate, the wind load per unit area, and the rain load per unit area. The tensile force and offset angle data of the expandable steel plate during the wind and rain load test are measured by the sensor unit, and the tensile force data and offset angle data are transmitted to the main control unit through the signal receiving unit.

7. The method for testing the wind and rain load on transmission lines according to claim 6, characterized in that, The steps for obtaining the design parameters of the insulator conductor system of the three-tower, two-span transmission line and calculating the load test data of the transmission line include: The design parameters of the insulator conductor system for a three-tower, two-span transmission line are obtained. The design parameters include the design parameters of the lines on both sides of the suspension insulator and the design parameters of the suspension insulator itself. The design parameters of the lines on both sides of the suspension insulator include the horizontal span, elevation difference, vertical load ratio, horizontal stress, and line radius of the lines on both sides. The design parameters of the suspension insulator include the weight, length, and shed diameter of the suspension insulator. Based on the design parameters of the suspension insulator, the wind-receiving area of ​​the insulator is calculated, and based on the design parameters of the lines on both sides of the suspension insulator, the wind-receiving area of ​​the transmission line, the rainfall-receiving area of ​​the transmission line, and the weight of the transmission line conductor are calculated. Based on the wind-receiving area of ​​the insulator and the wind-receiving area of ​​the transmission line, the equivalent wind-receiving area of ​​the insulator-conductor system of the three-tower two-span transmission line is calculated, and the rainfall-receiving area of ​​the transmission line is taken as the equivalent rainfall-receiving area of ​​the insulator-conductor system of the three-tower two-span transmission line. The total weight of the insulator and conductor system of the three-tower two-span transmission line is calculated based on the weight of the suspension insulator and the weight of the transmission line conductor. Based on the preset wind speed and rainfall intensity, calculate the wind load and rain load of the insulator conductor system of the three-tower two-span transmission line; Based on the wind load, the rain load, the equivalent wind-receiving area, and the equivalent rain-receiving area, the wind load per unit area and the rain load per unit area are calculated.

8. The method for testing the wind and rain load on transmission lines according to claim 7, characterized in that, The steps for conducting a wind and rain load test by controlling the expansion area of ​​the expandable steel plate, the air volume of the air duct, and the rainfall of the rain shower through the main control unit include: The main control unit controls the tilt angle and horizontal position of the suspension unit so that the retractable steel plate and the first laser scanning unit are on the same horizontal line, and the retractable steel plate is located directly below the second laser scanning unit. The retractable steel plate is scanned by the first laser scanning unit and the second laser scanning unit to obtain the horizontal scanning area and the ground projection area, respectively. The ratio between the horizontal scan area and the ground projection area is taken as the first ratio, and the ratio between the equivalent wind-receiving area and the equivalent rainfall-receiving area is taken as the second ratio. The main control unit controls the expansion and contraction area of ​​the expandable steel plate to make the first ratio equal to the second ratio. The equivalent wind load of the retractable steel plate is calculated based on the wind load per unit area and the horizontal scanning area, and the equivalent rain load of the retractable steel plate is calculated based on the rain load per unit area and the ground projection area. The main control unit controls the power of the fan so that the air volume of the duct is the same as the air volume corresponding to the equivalent wind load. The main control unit controls the first servo motor so that the rainfall from the rain shower is equal to the rainfall corresponding to the equivalent rain load.

9. The method for testing the wind and rain load on transmission lines according to claim 8, characterized in that, The wind-receiving area of ​​the insulator is calculated using the following formula: S A =k*D*l In the formula, S A denoted as the wind-receiving area of ​​the insulator, k is the equivalent area coefficient of the insulator, D is the diameter of the shed of the suspension insulator, and l is the length of the suspension insulator. The wind-receiving area of ​​the transmission line is calculated using the following formula: In the formula, S B denoted as the windward area of ​​the transmission line, k1 as the equivalent area coefficient of the line, a as the line radius, θ as the wind direction angle, b1 and b2 as the horizontal span between the two spans of the line, c1 and c2 as the elevation difference between the two spans of the line, γ as the vertical load ratio, and σ as the horizontal stress. The equivalent wind-receiving area is calculated using the following formula: S1=S A +S B The equivalent rainfall-receiving area is calculated using the following formula: In the formula, β is the angle of rainfall; The weight of the transmission line conductors is calculated using the following formula: The total weight of the insulator conductor system for the three-tower, two-span transmission line is calculated using the following formula: G=G j +G l In the formula, G j The weight of the suspension insulator; The wind load per unit area is calculated using the following formula: In the formula, F1 is the wind load of the insulator conductor system of the three-tower two-span transmission line; The unit area rain load is calculated using the following formula: In the formula, F2 is the rain load of the insulator conductor system of the three-tower two-span transmission line; The equivalent wind load is calculated using the following formula: F3=w1*S 1c In the formula, S 1c The horizontal scan area; The equivalent rain load is calculated using the following formula: F4=w2*S 2c In the formula, S 2c This represents the projected area of ​​the ground.

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