External positioning system and method for transformer internal inspection robot

Abstract

An external positioning system for a transformer internal inspection robot includes: at least n external sound source beacons, at least one reference positioning device, and the internal inspection robot, wherein n is greater than or equal to 3; the at least n external sound source beacons are installed at n known locations on at least n different planes of the transformer casing; the reference positioning device is installed at any other known location on the transformer casing besides the three known locations, and the other known location serves as the original known location of the reference positioning device. This invention eliminates the need for transformer design drawings and does not rely on the robot itself, enabling precise three-dimensional positioning of the robot inside the transformer through external sound source beacons. This facilitates accurate fault location within the transformer and rapid recovery of the robot after loss of control. Research on this technology is at the forefront both domestically and internationally. Furthermore, the introduction of the reference positioning device improves positioning accuracy.

Description

Technical Field

[0001] This invention relates to the field of robotics, and in particular to an external positioning system and method for a transformer internal inspection robot. Background Technology

[0002] Large oil-immersed power transformers are core equipment of the power grid, characterized by their large capacity, high value, and complex structure, making them a key focus in substation operation. When a transformer malfunctions, a power outage is often required to inspect and locate internal defects in order to confirm the type of fault and determine a repair plan. Current methods involve draining the oil from the transformer and having professionals manually enter the transformer to locate the fault, which is time-consuming, labor-intensive, and poses significant safety hazards.

[0003] In recent years, with the development of artificial intelligence technology, the idea of ​​using robots to perform internal inspections of transformers with oil content has gradually matured. According to research by scholars and industry engineers, robots have significant advantages in performing internal inspections of transformers, replacing manual labor. (See [link to relevant documentation]). Figure 1 As shown in the figure, the left side represents the characteristics of the traditional solution, and the right side represents the characteristics of the microrobot internal inspection.

[0004] In 2018, ABB released its first robot for detecting transformer oil, TXplore, and domestic companies have also made some attempts to develop robots.

[0005] Currently, these robots are not miniaturized enough and mainly suffer from the following problems:

[0006] 1) Compared to the expectations of the front line, the existing internal inspection robot is too large and needs to be entered through the hand hole at the bottom of the bushing, which is only suitable for specific models of transformers;

[0007] 2) Due to the complex internal environment of oil-filled transformers, the existing technology cannot achieve precise positioning of such robots. In the event of robot failure, recovery is difficult and may cause secondary damage to the transformer. Summary of the Invention

[0008] In view of this, the present invention proposes an external positioning system and method for a transformer internal inspection robot.

[0009] On one hand, this invention discloses an external positioning system for a transformer internal inspection robot, comprising:

[0010] At least n external sound source beacons and at least one reference positioning device and an internal inspection robot, wherein n is greater than or equal to 3;

[0011] The at least n external sound source beacons are used to be installed at at least n known locations on at least n different planes of the transformer casing;

[0012] The reference positioning device is used to be installed on the transformer casing at any other known location besides the three known locations, and the other known location is used as the original known location of the reference positioning device.

[0013] in,

[0014] The reference positioning device includes: a first sound sensor, a first processor, and a first memory;

[0015] The internal inspection robot includes: a second sound sensor, a second processor, and a second memory.

[0016] Preferred,

[0017] n is 4.

[0018] Preferred,

[0019] The reference positioning device is also used to calculate its own current position based on sound signals emitted by at least n external sound source beacons;

[0020] It is further used to calculate the correction parameter by subtracting its current position from the original known position.

[0021] Preferred,

[0022] The internal inspection robot is also used to calculate its current position based on sound signals emitted by at least n external sound source beacons.

[0023] It is further used to calculate the corrected current position based on its current position and the correction parameters.

[0024] On the other hand, the present invention also discloses a method for positioning using any of the above-mentioned systems, comprising the following steps:

[0025] S100. Arrange the n external sound source beacons and reference positioning devices, and measure their precise positions;

[0026] S200: Set the characteristic signal for each beacon and synchronize the clocks of all beacons;

[0027] S300, place the internal inspection robot into the transformer, and synchronize the clocks of the internal inspection robot and the reference positioning device with the clocks of all beacons;

[0028] S400: The reference positioning device receives sound signals from at least 3 determined external sound source beacons out of n external sound source beacons, and calculates the current position of the reference positioning device accordingly.

[0029] S500: The reference positioning device calculates the correction parameters by subtracting its current position from the original known position.

[0030] S600: The internal inspection robot calculates its current position based on sound signals emitted by at least three identical external sound source beacons.

[0031] S700: The internal inspection robot calculates its corrected current position based on its current position and the correction parameters.

[0032] Preferred,

[0033] In step S200, differential Manchester coding is used to set the characteristic signal for each beacon.

[0034] Furthermore, the present invention also makes the following limitations regarding the internal inspection robot:

[0035] The internal inspection robot is cylindrical in shape.

[0036] Preferred,

[0037] The cylindrical internal inspection robot includes at least three propellers for movement in transformer oil.

[0038] Preferred,

[0039] The at least three propeller thrusters enable the internal inspection robot to move in at least the x, y, and z directions.

[0040] Preferred,

[0041] The cylindrical internal inspection robot has dimensions of φ125mm*180mm.

[0042] Preferred,

[0043] The internal inspection robot enters and exits the transformer through the transformer's pressure relief valve.

[0044] Thus, the present invention achieves at least the following technical effects:

[0045] (1) The present invention overcomes the shortcomings of the prior art, which is that the robot is too large and needs to enter through the hand hole at the bottom of the bushing, and is only applicable to specific types of transformers; the internal inspection robot in the present invention can freely enter and exit various types of transformers from the pressure relief valve position of the transformer.

[0046] (2) The positioning system and method of the present invention do not require transformer design drawings and do not depend on the robot itself. They can achieve precise three-dimensional positioning of the robot inside the transformer through external sound source beacons, which helps to accurately locate faults inside the transformer and quickly recover the robot after it goes out of control. The research on related technologies is at the forefront at home and abroad. Furthermore, the introduction of the reference positioning device improves the accuracy of positioning. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a comparative diagram of existing technologies that utilize robots and manual labor for internal inspection of transformers;

[0049] Figure 2 This is a schematic diagram of the external positioning system layout in one embodiment of the present invention;

[0050] Figure 3 This is a schematic diagram of an external positioning method according to one embodiment of the present invention;

[0051] Figure 4 This is a schematic diagram of ball positioning when locating the robot inside the transformer in one embodiment of the present invention. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will be described in conjunction with the appendices in the embodiments of the present invention. Figures 1 to 4 The technical solutions in the embodiments of the present invention will be clearly and completely described herein. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0053] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0054] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0055] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0056] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0057] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0058] In one embodiment, the present invention discloses an external positioning system for a transformer internal inspection robot, comprising:

[0059] At least n external sound source beacons and at least one reference positioning device and an internal inspection robot, wherein n is greater than or equal to 3;

[0060] The at least n external sound source beacons are used to be installed at at least n known locations on at least n different planes of the transformer casing;

[0061] The reference positioning device is used to be installed on the transformer casing at any other known location besides the three known locations, and the other known location is used as the original known location of the reference positioning device.

[0062] in,

[0063] The reference positioning device includes: a first sound sensor, a first processor, and a first memory;

[0064] The internal inspection robot includes: a second sound sensor, a second processor, and a second memory.

[0065] In another embodiment, see Figure 2 The diagram illustrates four external sound source beacons and their positions: position 1, position 2, position 3, and position 4. It's understandable that, based on the number of coordinates in three-dimensional space, three external sound source beacons are sufficient as a minimum requirement. More external sound source beacons allow for faster and more accurate position calculations.

[0066] In addition, Figure 2The diagram also illustrates the location where the reference positioning device is installed: the reference positioning point. It can be understood that the reference positioning point is the original known location of the reference positioning device. Since both the reference positioning device and the external sound source beacon are installed outside the transformer, this invention eliminates the need for transformer design drawings and does not rely on the robot itself. It enables precise three-dimensional positioning of the robot inside the transformer via the external sound source beacon, facilitating accurate fault location within the transformer and rapid recovery of the robot after it goes out of control. Research on this technology is at the forefront both domestically and internationally. Furthermore, the introduction of the reference positioning device improves the accuracy of positioning.

[0067] In another embodiment,

[0068] n is 4.

[0069] In another embodiment,

[0070] The reference positioning device is also used to calculate its own current position based on sound signals emitted by at least n external sound source beacons;

[0071] It is further used to calculate the correction parameter by subtracting its current position from the original known position.

[0072] Thus, the crucial role of the reference positioning device in this invention becomes clear. The reference positioning device is used to assist in the positioning of the internal inspection robot.

[0073] In another embodiment,

[0074] The internal inspection robot is also used to calculate its current position based on sound signals emitted by at least n external sound source beacons.

[0075] It is further used to calculate the corrected current position based on its current position and the correction parameters.

[0076] See Figure 3 In another embodiment, the present invention also discloses a method for positioning using any of the above-described systems, comprising the following steps:

[0077] S100. Arrange the n external sound source beacons and reference positioning devices, and measure their precise positions;

[0078] S200: Set the characteristic signal for each beacon and synchronize the clocks of all beacons;

[0079] S300, place the internal inspection robot into the transformer, and synchronize the clocks of the internal inspection robot and the reference positioning device with the clocks of all beacons;

[0080] S400: The reference positioning device receives sound signals from at least 3 determined external sound source beacons out of n external sound source beacons, and calculates the current position of the reference positioning device accordingly.

[0081] S500: The reference positioning device calculates the correction parameters by subtracting its current position from the original known position.

[0082] S600: The internal inspection robot calculates its current position based on sound signals emitted by at least three identical external sound source beacons.

[0083] S700: The internal inspection robot calculates its corrected current position based on its current position and the correction parameters.

[0084] It is understandable that the above embodiments use differential positioning to compensate for the inaccuracy of single-point positioning.

[0085] In another embodiment,

[0086] In step S200, differential Manchester coding is used to set the characteristic signal for each beacon.

[0087] Furthermore, the present invention also makes the following limitations regarding the internal inspection robot:

[0088] The internal inspection robot is cylindrical in shape.

[0089] In another embodiment,

[0090] The cylindrical internal inspection robot includes at least three propellers for movement in transformer oil.

[0091] In another embodiment,

[0092] The at least three propeller thrusters enable the internal inspection robot to move in at least the x, y, and z directions.

[0093] In another embodiment,

[0094] The cylindrical internal inspection robot has dimensions of φ125mm*180mm.

[0095] In another embodiment,

[0096] The internal inspection robot enters and exits the transformer through the transformer's pressure relief valve.

[0097] In another embodiment, the present invention also discloses a method for positioning using the above-described external positioning system, comprising the following steps:

[0098] Four external sound source beacons were fixed around the transformer under test.

[0099] To measure the precise location of the fixed beacon;

[0100] Use differential Manchester coding to define the beacon characteristic signal;

[0101] The internal inspection robot and reference positioning device are deployed and synchronized with the clocks of four beacons;

[0102] The sound signals emitted by the four beacons are received using the first sound sensor of the internal inspection robot and the second sound sensor of the reference positioning device.

[0103] The position of the internal inspection robot is calculated in real time using the current position of the reference positioning device and the original known position measured by the reference positioning device.

[0104] In another embodiment,

[0105] This invention provides a sound source beacon localization method based on differential Manchester code, comprising the following steps:

[0106] The sound source beacons are fixed around the transformer under test. There are no specific requirements for the position of the beacons. They only need to be in a spatial position that is easy to measure accurately and that the four beacons are not on the same plane.

[0107] Measure the precise position of the fixed beacon, such as the current position (spatial coordinates) of the four beacons Position1, Position2, Position3, and Position4;

[0108] Four beacon feature coded signals are set using differential Manchester coding.

[0109] The internal inspection robot and reference positioning device are deployed and synchronized with the clocks of four beacons;

[0110] Using the first sound sensor of the internal inspection robot and the second sound sensor of the reference positioning device, the sound signals emitted by the four beacons are received, and the distances d1, d2, d3, and d4 from the four beacons to the receiving device to be located are measured (Note: the receiving device is the internal inspection robot, or more precisely, the sound sensor of the internal inspection robot).

[0111] Find the location of the internal inspection robot that needs to be located.

[0112] In another embodiment,

[0113] Determining the location of the internal inspection robot involves the following steps:

[0114] (1) After receiving the signal, the internal inspection robot first determines that it is closest to a certain beacon, that is, the first step of rough positioning: the internal inspection robot first receives the signals emitted by each beacon, sorts the signals according to the strength of the signals, and thus determines its approximate position.

[0115] (2) After rough positioning, precise positioning is performed: positioning is based on other beacon signals. The time taken to receive different beacons within one cycle is determined. Spheres are drawn with radii based on the propagation distances of different beacons. The intersection of multiple spheres is the location of the internal inspection robot. For example... Figure 4 As shown.

[0116] While the above embodiments represent an innovative method for positioning transformer internal inspection robots and constitute a contribution of this invention to the prior art, it should be noted that this invention is not limited to the specific spherical algorithm described above. Theoretically, any algorithm that uses multiple sound sources for localization can be used in this invention. However, it is understood that the greater technical contribution of this invention lies in the collaboration between the reference positioning device and the internal inspection robot.

[0117] Since the reference positioning device at the reference positioning point is equivalent to another robot at a known location, it is used to assist in calculating the positioning of the internal inspection robot. Therefore, the same algorithm as in the above embodiment can also be used to position the reference positioning device. However, since the original known position of the reference positioning device is determined and known, a correction parameter can be calculated by subtracting the original known position from the obtained position of the reference positioning device, which can then be used to correct the positioning of the internal inspection robot.

[0118] It is understood that this invention innovatively utilizes the concept of negative feedback to accurately calculate the position of the internal inspection robot and provides a detailed new solution.

[0119] In another embodiment,

[0120] The reference positioning point is the original known position of the reference positioning device, and its spatial coordinates (X0, Y0, Z0) can be accurately measured.

[0121] Through algorithms (such as those described in the previous examples and...) Figure 4 The spherical calculation method shown calculates the coordinates (X1, Y1, Z1) of the reference positioning device.

[0122] The correction parameters can be obtained as follows:

[0123] X-axis: X * = (X1-X0), Y-axis: Y * = (Y1-Y0), Z-axis: Z * =(Z1-Z0);

[0124] For the calculated position (X, Y, Z) of the internal inspection robot, the position of the internal inspection robot is corrected to (X', Y', Z') through the negative feedback of the correction parameters, where:

[0125] X' = ​​X - X *， Y' = Y - Y * Z' = Z - Z *

[0126] In summary, the present invention also has the following technical effects:

[0127] Since the propagation of acoustic signals in a transformer is not shielded by the transformer's structure, this invention increases the accuracy of navigation and positioning for the transformer internal inspection robot.

[0128] This invention utilizes multiple external sound source beacons and differential positioning to overcome the inaccuracy of single-point positioning. By adding a reference positioning device and its reference positioning point (i.e., the original known position), the positioning accuracy is improved, thereby correcting the positioning position of the internal inspection robot. This allows for effective and accurate real-time positioning of the internal inspection robot.

[0129] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An external positioning system for a transformer internal inspection robot, comprising: The system includes at least n external sound source beacons, at least one reference positioning device, and an internal inspection robot, where n is 4; four external sound source beacons facilitate faster and more accurate position calculation. The at least n external sound source beacons are used to be installed at at least n known locations on at least n different planes of the transformer casing; The reference positioning device is used to be installed on the transformer casing at any known location other than the three known locations, and the other known location is used as the original known location of the reference positioning device. in, The reference positioning device includes: a first sound sensor, a first processor, and a first memory; The internal inspection robot includes: a second sound sensor, a second processor, and a second memory; The reference positioning device is also used to calculate its own current position based on sound signals emitted by at least n external sound source beacons; It is further used to calculate the correction parameter by subtracting its current position from the original known position; The internal inspection robot is also used to calculate its current position based on sound signals emitted by at least n external sound source beacons. It is further used to calculate the corrected current position based on its current position and the correction parameters; The method for positioning using the system includes the following steps: Four external sound source beacons were fixed around the transformer under test. To measure the precise location of the fixed beacon; Use differential Manchester coding to define the beacon characteristic signal; The internal inspection robot and reference positioning device are deployed and synchronized with the clocks of four beacons; The sound signals emitted by the four beacons are received using the first sound sensor of the internal inspection robot and the second sound sensor of the reference positioning device. The position of the internal inspection robot is calculated in real time using the current position of the reference positioning device and the original known position measured by the reference positioning device. The cylindrical internal inspection robot has dimensions of φ125mm*180mm, and it enters and exits the transformer through the transformer's pressure relief valve. Determining the location of the internal inspection robot involves the following steps: (1) After receiving the signal, the internal inspection robot first determines that it is closest to a certain beacon, that is, the first step is rough positioning: the internal inspection robot first receives the signals emitted by each beacon, sorts the signals according to the signal strength, and thus determines its approximate position. (2) After rough positioning, perform precise positioning: Positioning is performed based on other beacon signals. In one cycle, the time taken to receive different beacons is determined. Based on the propagation path of different beacons, draw spheres with radii. The point where multiple spheres intersect is the location of the internal inspection robot.

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