Transformer winding omnibearing buckling deformation simulation device and oscillatory wave analysis method thereof

Abstract

The invention discloses a transformer winding omni-directional buckling deformation simulation device and an oscillatory wave analysis method thereof. Firstly, buckling deformation faults of different positions and different degrees of a transformer winding are simulated by using a cascade compression lifting cylinder and a controllable magnetic energy induction device, then oscillatory wave curve data of the winding in a normal state and different fault states are obtained by using a high-frequency oscillatory wave test system, and then multi-stage reconstruction processing is performed on an original oscillatory wave curve. Whether the winding breaks down or not is judged by calculating the extreme value offset degree Qe, after it is determined that the winding breaks down, the fault position of the winding is judged by calculating the maximum value eccentricity Qx, and meanwhile the fault degree of the winding is judged by calculating the minimum value eccentricity Qy. Omnibearing buckling deformation of the transformer winding can be effectively simulated, high-efficiency diagnosis of the winding state can be realized by using the characteristic parameters of the oscillatory waves, and reference is provided for engineering practice.

Description

Technical Field

[0001] The invention belongs to the technical field of transformer winding fault simulation, and in particular relates to a transformer winding omnidirectional warping deformation simulation device and an oscillation wave analysis method thereof. Background Art

[0002] In the power system, the transformer is one of the key components and is subjected to a variety of external and internal forces during operation. With the accumulation of force and action time, the deformation of the winding coil, insulation layer and loosening of the protective fixture will cause the winding to warp and deform at different positions and to different degrees, thereby causing damage to the winding machinery and insulation. In severe cases, it will affect the normal operation of the entire power system. Therefore, it is particularly important to conduct a comprehensive simulation and analysis of the transformer winding warping deformation failure in advance. Winding warping deformation is the most common type of fault in transformer windings. At present, there is still a lack of simulation devices for winding warping deformation faults at different positions and to different degrees and oscillation wave diagnostic analysis methods. Using a full-range warping deformation fault device for simulation and subsequent analysis and diagnosis by extracting oscillation wave characteristic parameters will help improve the accuracy of winding warping deformation faults.

[0003] At a certain frequency, the winding is equivalent to a distributed parameter network with a combination of inductance, capacitance, and resistance parameters. When the winding is warped, the equivalent distributed parameters change, and the winding oscillation charge and discharge cycle changes accordingly, thus affecting the peak value of the oscillation wave curve, the number of extreme points, the degree of peak deviation, and other changing trends. Therefore, building a full-range winding warping simulation device and judging the winding state by analyzing the characteristic changes of the transformer winding oscillation wave when the winding is warped is the focus, hot spot, and difficulty of transformer winding fault diagnosis in the future. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention proposes a transformer winding all-round warping deformation simulation device and an oscillation wave analysis method thereof, so as to explore the changes in the winding oscillation wave curve when the transformer winding is warped at different positions and to different degrees. It can effectively study the changing relationship between the winding warping deformation and the oscillation wave characteristics, thereby providing a reference for actual engineering.

[0005] The technical solution adopted by the present invention is:

[0006] A winding all-round warping deformation simulation device was built, which mainly includes a transformer body model (5) and a winding all-round warping deformation simulation device (10); the transformer body model is composed of an iron core column (6), a winding (7), an iron yoke (8), and a high-frequency bushing (4); a high-frequency and high-voltage oscillation wave generator (1) is connected to the top of the input bushing, and an oscillation wave signal collector (3) is connected to the output bushing through a harmonic filtering device (2); the winding all-round warping deformation simulation device mainly includes a step compression lifting cylinder I (13), a step compression lifting cylinder II (12), a step compression lifting cylinder III (11), a central control instrument (14), a mechanical universal wheel (15), and a controllable magnetic energy induction device (16); the step compression lifting cylinder is The control device (16) is divided into a mechanical control button (111), a device fixing ring belt (121), and a cross telescopic rod (131); the central control instrument (14) is further divided into an integrated control board (141) and a permanent magnetic adsorption sheet (142); the mechanical universal wheel (15) is divided into a mechanical movable caster (151) and a caster connecting piece (152); the controllable magnetic energy induction device (16) is divided into a controllable magnetic energy induction disk (161), an electrostatic shielding net (162), and a magnetic disk connecting rod (163); the controllable magnetic energy induction disk (161) is further divided into an adjustable magnetic energy induction sheet (164), a fixing groove (165), an electromagnetic connection line (166), a split connection plate (167), a magnetic flux shield (168), and a magnetic induction insulating layer (169);

[0007] The transformer winding omnidirectional warping deformation simulation and oscillation wave analysis method includes the following steps:

[0008] Step 1: Simulate the winding warping deformation faults at different locations and in various degrees, including:

[0009] 1) Connecting the controllable magnetic energy induction device (16) to the step compression lifting cylinder I (13), the step compression lifting cylinder II (12), and the step compression lifting cylinder III (11) through a magnetic disk connecting rod (163), fixing the controllable magnetic energy induction device (16) with a device fixing ring belt (121) to achieve 360-degree all-round rotation, placing the step compression lifting cylinder III on the surface of the central control instrument (14), and connecting the inside through wires, the integrated control board (141) in the central control instrument (14) issues a command to control the magnetic strength of the adjustable magnetic energy induction sheet (164) through the magnetic disk connecting rod (163), and at the same time controls the permanent magnetic adsorption sheet (142) to generate a strong magnetic repulsion, so that the controllable magnetic energy induction device (16) has a minimum height;

[0010] 2) The step compression lifting cylinder I (13) is installed in the step compression lifting cylinder II (12), and the step compression lifting cylinder II (12) is installed in the step compression lifting cylinder III (11). The step compression lifting cylinder can realize the corresponding matching of the controllable magnetic energy induction device (16) and the coils (71) at different heights of the winding (7). The cross telescopic rod (131) is placed at the connection between two adjacent step compression lifting cylinders, and the step compression lifting cylinder I (13) and the step compression lifting cylinder II (12) can be smoothly raised or lowered by stretching or contracting. The mechanical control button (111) is embedded in the surface of the step compression lifting cylinder III (11), and is set to three in total, which respectively control the lifting and lowering of the step compression lifting cylinder I (13), the step compression lifting cylinder II (12), and the step compression lifting cylinder III (11) from top to bottom;

[0011] 3) adjusting the heights of two adjacent controllable magnetic energy induction devices (16) to the upper and lower parts of a certain coil (71), adjusting the split connection plate (167) so that the controllable magnetic energy induction device (16), the magnetic flux shield (168), and the magnetic induction insulating layer (169) are split into two semicircular structure devices along the diameter direction, and then reorganizing them around the central axis of the core column, so that the inner ring of the magnetic induction insulating layer (169) is completely in contact with the core, the controllable magnetic energy induction device (16) and the winding have the same outer diameter, and the cross-sections overlap along the axial direction, the controllable magnetic energy induction device (16), the magnetic flux shield (168), the magnetic induction insulating layer (169) and the core column remain axially parallel, and the centroids of the four cross-sections overlap;

[0012] 4) A magnetic induction insulating layer (169) is placed between the magnetic flux shield (168) and the adjustable magnetic energy induction sheet (164) to reduce the electromagnetic interference between the two. The adjustable magnetic energy induction sheet (164) is placed in the fixed groove (165) and connected and fixed to each other by an electromagnetic connecting line (166) to perform an electro-magnetic conversion. The magnetic flux shield (168) is turned on to reduce the external excitation magnetic energy interference on the core column. The corresponding adjustable magnetic energy induction sheets (164) in two adjacent controllable magnetic energy induction disks (161) are adjusted to generate different values ​​of attraction or repulsion at specific positions of the winding coil (71), thereby causing the winding to warp and deform. When the device is turned off, the electrostatic shielding net (162) is turned on;

[0013] 5) Repeat the above steps to simulate winding warping deformation faults at different locations and degrees;

[0014] Step 2: Conduct oscillation wave testing and fault analysis of transformer windings under different conditions, including:

[0015] 1) connecting the input end of the winding (7) to the excitation side of the high-frequency bushing (4) through a wire, and connecting the output end of the winding (7) to the response side of the high-frequency bushing (4);

[0016] 2) directly connecting the response side of the high-frequency bushing (4) to the harmonic filter device (2), and then connecting the harmonic filter device (2) to the oscillation wave signal collector (3);

[0017] 3) controlling the high-voltage oscillation wave generator (1) to generate a periodically changing high-frequency pulse signal, injecting the signal into the winding through the input end of the winding (7), and performing periodic oscillation charging and discharging through the winding equivalent RLC network;

[0018] 4) Repeat the above process to obtain transformer winding oscillation wave data under normal conditions and different warping deformation fault conditions through the oscillation wave signal collector (3);

[0019] 5) Use the decomposition and permutation function to perform multi-level reconstruction of the obtained oscillation wave curve:

[0020] (1)

[0021] In the formula, C(x) is the decomposition permutation function, M is the optimal reconstruction level, and p k is the decomposition coefficient, q k is the permutation term coefficient, is a smooth graded function, To reconstruct the mother wavelet function, And j is the scale, Z is a natural number, and ;

[0022] 6) Calculate the maximum eccentricity Q of the reconstructed oscillation wave curve x and minimum eccentricity Q y :

[0023] (2)

[0024] (3)

[0025] Where m and n are the number of maximum and minimum values ​​in the reconstructed oscillation wave curve, j and i are the maximum sequence variables and minimum sequence variables, respectively. j and i are the horizontal coordinates of the jth maximum point and the vertical coordinates of the ith minimum point, respectively. max ,y min , and y 0 、x 0 They are respectively the maximum horizontal coordinate in the maximum point, the minimum vertical coordinate in the minimum point, the initial horizontal coordinate in the maximum point, and the initial vertical coordinate in the minimum point.

[0026] 7) From the above maximum eccentricity Q x and minimum eccentricity Q yThe winding fault condition can be judged: when the extreme value deviation When the winding is normal, it is judged that the winding is normal, otherwise the winding has a warping deformation fault; according to the maximum eccentricity Q x Determine the location of winding fault: When the transformer winding is warped, it is judged that the upper part is warped. When the transformer winding is bent, the middle part is judged to be warped; when When the transformer winding bottom is warped, it is judged that the transformer winding bottom is warped and deformed; according to the minimum eccentricity Q y Determine the degree of winding fault: When the transformer winding is judged to have a slight warping deformation fault; when When the transformer winding is judged to have a moderate warping deformation fault; when It is judged that the transformer winding has severe warping and deformation fault.

[0027] In the formula, is the extreme value deviation degree of the optimal reconstruction series M=15; , and , They are the maximum eccentricity, minimum eccentricity when the optimal reconstruction series M=10 and the maximum eccentricity, minimum eccentricity when the optimal reconstruction series M=20 respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a wiring diagram of the winding oscillation wave overall test system of the present invention;

[0029] FIG2 (a) is a schematic diagram of a device for simulating omnidirectional warping deformation of a winding according to the present invention;

[0030] FIG2 (b) is a structural diagram of a controllable magnetic energy induction disk according to the present invention;

[0031] Figure 3 It is a flow chart of the present invention; DETAILED DESCRIPTION

[0032] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0033] The transformer winding omnidirectional warping deformation simulation device mainly comprises a transformer body model (5) and a winding omnidirectional warping deformation simulation device (10); the transformer body model is composed of an iron core column (6), a winding (7), an iron yoke (8), and a high-frequency bushing (4); a high-frequency and high-voltage oscillation wave generator (1) is connected to the top of the input bushing, and an oscillation wave signal collector (3) is connected to the output bushing through a harmonic filtering device (2); the winding omnidirectional warping deformation simulation device mainly comprises a step compression lifting cylinder I (13), a step compression lifting cylinder II (12), a step compression lifting cylinder III (11), a central control instrument (14), a mechanical universal wheel (15), and a controllable magnetic energy induction device (16); the step compression lifting cylinder is The control device (16) is divided into a mechanical control button (111), a device fixing ring belt (121), and a cross telescopic rod (131); the central control instrument (14) is further divided into an integrated control board (141) and a permanent magnetic adsorption sheet (142); the mechanical universal wheel (15) is divided into a mechanical movable caster (151) and a caster connecting piece (152); the controllable magnetic energy induction device (16) is divided into a controllable magnetic energy induction disk (161), an electrostatic shielding net (162), and a magnetic disk connecting rod (163); the controllable magnetic energy induction disk (161) is further divided into an adjustable magnetic energy induction sheet (164), a fixing groove (165), an electromagnetic connection line (166), a split connection plate (167), a magnetic flux shield (168), and a magnetic induction insulating layer (169);

[0034] When the present invention is used, the main steps are as follows:

[0035] Step 1: Simulate the winding warping deformation faults at different locations and in various degrees, including:

[0036] 1) Connecting the controllable magnetic energy induction device (16) to the step compression lifting cylinder I (13), the step compression lifting cylinder II (12), and the step compression lifting cylinder III (11) through a magnetic disk connecting rod (163), fixing the controllable magnetic energy induction device (16) with a device fixing ring belt (121) to achieve 360-degree all-round rotation, placing the step compression lifting cylinder III on the surface of the central control instrument (14), and connecting the inside through wires, the integrated control board (141) in the central control instrument (14) issues a command to control the magnetic strength of the adjustable magnetic energy induction sheet (164) through the magnetic disk connecting rod (163), and at the same time controls the permanent magnetic adsorption sheet (142) to generate a strong magnetic repulsion, so that the controllable magnetic energy induction device (16) has a minimum height;

[0037] 2) The step compression lifting cylinder I (13) is installed in the step compression lifting cylinder II (12), and the step compression lifting cylinder II (12) is installed in the step compression lifting cylinder III (11). The step compression lifting cylinder can realize the corresponding matching of the controllable magnetic energy induction device (16) and the coils (71) at different heights of the winding (7). The cross telescopic rod (131) is placed at the connection between two adjacent step compression lifting cylinders, and the step compression lifting cylinder I (13) and the step compression lifting cylinder II (12) can be smoothly raised or lowered by stretching or contracting. The mechanical control button (111) is embedded in the surface of the step compression lifting cylinder III (11), and is set to three in total, which respectively control the lifting and lowering of the step compression lifting cylinder I (13), the step compression lifting cylinder II (12), and the step compression lifting cylinder III (11) from top to bottom;

[0038] 3) adjusting the heights of two adjacent controllable magnetic energy induction devices (16) to the upper and lower parts of a certain coil (71), adjusting the split connection plate (167) so that the controllable magnetic energy induction device (16), the magnetic flux shield (168), and the magnetic induction insulating layer (169) are split into two semicircular structure devices along the diameter direction, and then reorganizing them around the central axis of the core column, so that the inner ring of the magnetic induction insulating layer (169) is completely in contact with the core, the controllable magnetic energy induction device (16) and the winding have the same outer diameter, and the cross-sections overlap along the axial direction, the controllable magnetic energy induction device (16), the magnetic flux shield (168), the magnetic induction insulating layer (169) and the core column remain axially parallel, and the centroids of the four cross-sections overlap;

[0039] 4) A magnetic induction insulating layer (169) is placed between the magnetic flux shield (168) and the adjustable magnetic energy induction sheet (164) to reduce the electromagnetic interference between the two. The adjustable magnetic energy induction sheet (164) is placed in the fixed groove (165) and connected and fixed to each other by an electromagnetic connecting line (166) to perform an electro-magnetic conversion. The magnetic flux shield (168) is turned on to reduce the external excitation magnetic energy interference on the core column. The corresponding adjustable magnetic energy induction sheets (164) in two adjacent controllable magnetic energy induction disks (161) are adjusted to generate different values ​​of attraction or repulsion at specific positions of the winding coil (71), thereby causing the winding to warp and deform. When the device is turned off, the electrostatic shielding net (162) is turned on;

[0040] 5) Repeat the above steps to simulate winding warping deformation faults at different locations and degrees;

[0041] Step 2: Conduct oscillation wave testing and fault analysis of transformer windings under different conditions, including:

[0042] 1) connecting the input end of the winding (7) to the excitation side of the high-frequency bushing (4) through a wire, and connecting the output end of the winding (7) to the response side of the high-frequency bushing (4);

[0043] 2) directly connecting the response side of the high-frequency bushing (4) to the harmonic filter device (2), and then connecting the harmonic filter device (2) to the oscillation wave signal collector (3);

[0044] 3) controlling the high-voltage oscillation wave generator (1) to generate a periodically changing high-frequency pulse signal, injecting the signal into the winding through the input end of the winding (7), and performing periodic oscillation charging and discharging through the winding equivalent RLC network;

[0045] 4) Repeat the above process to obtain transformer winding oscillation wave data under normal conditions and different warping deformation fault conditions through the oscillation wave signal collector (3);

[0046] 5) Use the decomposition and permutation function to perform multi-level reconstruction of the obtained oscillation wave curve:

[0047] (1)

[0048] In the formula, C(x) is the decomposition permutation function, M is the optimal reconstruction level, and p k is the decomposition coefficient, q k is the permutation term coefficient, is a smooth graded function, To reconstruct the mother wavelet function, And j is the scale, Z is a natural number, and ;

[0049] 6) Calculate the maximum eccentricity Q of the reconstructed oscillation wave curve x and minimum eccentricity Q y :

[0050] (2)

[0051] (3)

[0052] Where m and n are the number of maximum and minimum values ​​in the reconstructed oscillation wave curve, j and i are the maximum sequence variables and minimum sequence variables, respectively. j and i are the horizontal coordinates of the jth maximum point and the vertical coordinates of the ith minimum point, respectively. max ,y min , and y 0 、x 0 They are respectively the maximum horizontal coordinate in the maximum point, the minimum vertical coordinate in the minimum point, the initial horizontal coordinate in the maximum point, and the initial vertical coordinate in the minimum point.

[0053] 7) From the above maximum eccentricity Q x and minimum eccentricity Q yThe winding fault condition can be judged: when the extreme value deviation When the winding is normal, it is judged that the winding is normal, otherwise the winding has a warping deformation fault; according to the maximum eccentricity Q x Determine the location of winding fault: When the transformer winding is warped, it is judged that the upper part is warped. When the transformer winding is bent, the middle part is judged to be warped; when When the transformer winding bottom is warped, it is judged that the transformer winding bottom is warped and deformed; according to the minimum eccentricity Q y Determine the degree of winding fault: When the transformer winding is judged to have a slight warping deformation fault; when When the transformer winding is judged to have a moderate warping deformation fault; when It is judged that the transformer winding has severe warping and deformation fault.

[0054] In the formula, is the extreme value deviation degree of the optimal reconstruction series M=15; , and , They are the maximum eccentricity, minimum eccentricity when the optimal reconstruction series M=10 and the maximum eccentricity, minimum eccentricity when the optimal reconstruction series M=20 respectively.

Claims

1. A transformer winding omnidirectional warping deformation simulation device and an oscillation wave analysis method thereof, characterized in that: The invention mainly comprises a transformer body model (5) and a winding omnidirectional warping deformation simulation device (10); the transformer body model is composed of an iron core column (6), a winding (7), an iron yoke (8), and a high-frequency bushing (4); a high-frequency and high-voltage oscillation wave generator (1) is connected to the top of the input bushing; an oscillation wave signal collector (3) is connected to the output bushing through a harmonic filtering device (2); the winding omnidirectional warping deformation simulation device mainly comprises a step compression lifting cylinder I (13), a step compression lifting cylinder II (12), a step compression lifting cylinder III (11), a central control instrument (14), a mechanical universal wheel (15), and a controllable magnetic energy induction device (16); the step compression lifting cylinder is further divided into a mechanical control button (111), device fixing ring belt (121), cross telescopic rod (131); the central control instrument (14) is further divided into an integrated control board (141), a permanent magnetic adsorption sheet (142); the mechanical universal wheel (15) is divided into a mechanical movable caster (151), a caster connecting piece (152); the controllable magnetic energy induction device (16) is divided into a controllable magnetic energy induction disk (161), an electrostatic shielding net (162), and a disk connecting rod (163); the controllable magnetic energy induction disk (161) is further divided into an adjustable magnetic energy induction sheet (164), a fixed groove (165), an electromagnetic connection line (166), a split connection plate (167), a magnetic flux shield (168), and a magnetic induction insulating layer (169); The transformer winding omnidirectional warping deformation simulation and oscillation wave analysis method includes the following steps: Step 1: Simulate the winding warping deformation faults at different locations and in various degrees, including: 1) Connecting the controllable magnetic energy induction device (16) to the step compression lifting cylinder I (13), the step compression lifting cylinder II (12), and the step compression lifting cylinder III (11) through a magnetic disk connecting rod (163), fixing the controllable magnetic energy induction device (16) with a device fixing ring belt (121) to achieve 360-degree all-round rotation, placing the step compression lifting cylinder III on the surface of the central control instrument (14), and connecting the inside through wires, the integrated control board (141) in the central control instrument (14) issues a command to control the magnetic strength of the adjustable magnetic energy induction sheet (164) through the magnetic disk connecting rod (163), and at the same time controls the permanent magnetic adsorption sheet (142) to generate a strong magnetic repulsion, so that the controllable magnetic energy induction device (16) has a minimum height; 2) The step compression lifting cylinder I (13) is installed in the step compression lifting cylinder II (12), and the step compression lifting cylinder II (12) is installed in the step compression lifting cylinder III (11). The step compression lifting cylinder can realize the corresponding matching of the controllable magnetic energy induction device (16) and the coils (71) at different heights of the winding (7). The cross telescopic rod (131) is placed at the connection between two adjacent step compression lifting cylinders, and the step compression lifting cylinder I (13) and the step compression lifting cylinder II (12) can be smoothly raised or lowered by stretching or contracting. The mechanical control button (111) is embedded in the surface of the step compression lifting cylinder III (11), and is set to three in total, which respectively control the lifting and lowering of the step compression lifting cylinder I (13), the step compression lifting cylinder II (12), and the step compression lifting cylinder III (11) from top to bottom; 3) adjusting the heights of two adjacent controllable magnetic energy induction devices (16) to the upper and lower parts of a certain coil (71), adjusting the split connection plate (167) so that the controllable magnetic energy induction device (16), the magnetic flux shield (168), and the magnetic induction insulating layer (169) are split into two semicircular structure devices along the diameter direction, and then reorganizing them around the central axis of the core column, so that the inner ring of the magnetic induction insulating layer (169) is completely in contact with the core, the controllable magnetic energy induction device (16) and the winding have the same outer diameter, and the cross-sections overlap along the axial direction, the controllable magnetic energy induction device (16), the magnetic flux shield (168), the magnetic induction insulating layer (169) and the core column remain axially parallel, and the centroids of the four cross-sections overlap; 4) A magnetic induction insulating layer (169) is placed between the magnetic flux shield (168) and the adjustable magnetic energy induction sheet (164) to reduce the electromagnetic interference between the two. The adjustable magnetic energy induction sheet (164) is placed in the fixed groove (165) and connected and fixed to each other by an electromagnetic connecting line (166) to perform an electro-magnetic conversion. The magnetic flux shield (168) is turned on to reduce the external excitation magnetic energy interference on the core column. The corresponding adjustable magnetic energy induction sheets (164) in two adjacent controllable magnetic energy induction disks (161) are adjusted to generate different values ​​of attraction or repulsion at specific positions of the winding coil (71), thereby causing the winding to warp and deform. When the device is turned off, the electrostatic shielding net (162) is turned on; 5) Repeat the above steps to simulate winding warping deformation faults at different locations and degrees; Step 2: Conduct oscillation wave testing and fault analysis of transformer windings under different conditions, including: 1) connecting the input end of the winding (7) to the excitation side of the high-frequency bushing (4) through a wire, and connecting the output end of the winding (7) to the response side of the high-frequency bushing (4); 2) directly connecting the response side of the high-frequency bushing (4) to the harmonic filter device (2), and then connecting the harmonic filter device (2) to the oscillation wave signal collector (3); 3) controlling the high-voltage oscillation wave generator (1) to generate a periodically changing high-frequency pulse signal, injecting the signal into the winding through the input end of the winding (7), and performing periodic oscillation charging and discharging through the winding equivalent RLC network; 4) Repeat the above process to obtain transformer winding oscillation wave data under normal conditions and different warping deformation fault conditions through the oscillation wave signal collector (3); 5) Use the decomposition and permutation function to perform multi-level reconstruction of the obtained oscillation wave curve: （1） In the formula, C(x) is the decomposition permutation function, M is the optimal reconstruction level, and p k is the decomposition coefficient, q k is the permutation term coefficient, is a smooth graded function, To reconstruct the mother wavelet function, And j is the scale, Z is a natural number, and ; 6) Calculate the maximum eccentricity Q of the reconstructed oscillation wave curve x and minimum eccentricity Q y : （2） （3） Where m and n are the number of maximum and minimum values ​​in the reconstructed oscillation wave curve, j and i are the maximum sequence variables and minimum sequence variables, respectively. j and i are the horizontal coordinates of the jth maximum point and the vertical coordinates of the ith minimum point, respectively. max ,y min , y0, x0 are the maximum horizontal coordinate in the maximum point, the minimum vertical coordinate in the minimum point, the initial horizontal coordinate in the maximum point, and the initial vertical coordinate in the minimum point respectively. 7) From the above maximum eccentricity Q x and minimum eccentricity Q y The winding fault condition can be judged: when the extreme value deviation When the winding is normal, it is judged that the winding is normal, otherwise the winding has a warping deformation fault; according to the maximum eccentricity Q x Determine the location of winding fault: When the transformer winding is warped, it is judged that the upper part is warped. When the transformer winding is bent, the middle part is judged to be warped; when When the transformer winding bottom is warped, it is judged that the transformer winding bottom is warped and deformed; according to the minimum eccentricity Q y Determine the degree of winding fault: When the transformer winding is judged to have a slight warping deformation fault; when When the transformer winding is judged to have a moderate warping deformation fault; when It is judged that the transformer winding has severe warping and deformation fault. In the formula, is the extreme value deviation degree of the optimal reconstruction series M=15; , and , They are the maximum eccentricity, minimum eccentricity when the optimal reconstruction series M=10 and the maximum eccentricity, minimum eccentricity when the optimal reconstruction series M=20 respectively.

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