Calculation method of stator coil size of permanent magnet traction motor based on 3D scanning

Abstract

The present invention discloses a method for calculating the size of a permanent magnet traction motor stator forming coil based on three-dimensional scanning, the method comprising: obtaining three-dimensional point cloud data of the permanent magnet traction motor stator forming coil and performing point cloud preprocessing; smoothly cutting off the connecting lead part; taking the main direction of the permanent magnet traction motor stator forming coil as the x-axis and the direction perpendicular to the x-axis in the plane where the permanent magnet traction motor stator forming coil is located as the y-axis to establish a rectangular coordinate system; using the fitting method of numerical iterative optimization of the least squares adjustment method to establish the mathematical equation of the stator forming coil surface; finally calculating the normal vector of the coil surface point, the total length of the coil, the outer span and the nose height. The present invention obtains the key dimensions of the permanent magnet traction motor stator forming coil based on three-dimensional scanning technology, including the total length of the stator forming coil, the outer span and the nose height; in addition, parameters such as curvature can be obtained through the mathematical equation of the stator forming coil surface.

Description

Technical Field

[0001] The present invention belongs to the technical field of three-dimensional scanning dimension measurement of a permanent magnet traction motor stator forming coil, and in particular relates to a method for calculating the dimension of a permanent magnet traction motor stator forming coil based on three-dimensional scanning. Background Art

[0002] The stator forming coils in permanent magnet traction motors have complex shapes and structural dimensions. Point cloud modeling can provide a large amount of discrete point data, which can obtain a large amount of quantitative data of stator forming coils, improve the accuracy and repeatability of measurement, and accurately reflect the shape and curvature of the coils. 3D scanning point cloud modeling technology is suitable for measuring objects with complex geometric shapes, and can provide more comprehensive and detailed data for subsequent analysis, including the shape, size, surface curvature and other properties of the coils. These data can be used to generate accurate 3D models, and can also be used for further analysis such as simulation and optimization design. The manufacturing of permanent magnet traction motor stator forming coils based on 3D scanning technology can realize digital production, as well as online maintenance and management, and can facilitate the rapid inspection of stator forming coils, saving time and cost. Traditional vernier caliper measurement technology cannot provide these detailed data and can only obtain a small amount of dimensional data. The key dimension calculation method of the stator forming coils of the 3D scanning permanent magnet traction motor can quickly measure the key dimensions of coils of different models to meet the manufacturing requirements of motor stators of different models.

[0003] Compared with the traditional measurement method, the key dimension calculation method of permanent magnet traction motor stator forming coil based on 3D scanning technology has higher measurement accuracy and repeatability, while the latter is suitable for measuring the size of regular structures. Traditional measurement methods usually require the use of manual tools such as vernier calipers. The measurement accuracy and repeatability of these tools are affected by many factors such as the operator's skill level and environmental factors. They require a lot of time and manpower costs and are prone to errors. The key dimension calculation method of 3D scanning provides reference value for accurately measuring and analyzing the size of stator forming coils, improving detection accuracy and reducing production costs. Summary of the invention

[0004] The purpose of the present invention is to provide a method for calculating the size of a permanent magnet traction motor stator forming coil based on three-dimensional scanning, and to obtain the key dimensions of the permanent magnet traction motor stator forming coil based on three-dimensional scanning technology, including the total length, outer span and nose height of the stator forming coil.

[0005] The technical solution of the present invention is:

[0006] A method for calculating the size of a stator forming coil of a permanent magnet traction motor based on three-dimensional scanning, the method comprising:

[0007] Obtain the three-dimensional point cloud data of the permanent magnet traction motor stator formed coil and perform point cloud preprocessing;

[0008] Smoothly cut the connection lead wire part of the permanent magnet traction motor stator forming coil in the three-dimensional point cloud data;

[0009] A rectangular coordinate system is established with the main direction of the permanent magnet traction motor stator forming coil as the x-axis and the direction perpendicular to the x-axis in the plane where the permanent magnet traction motor stator forming coil is located as the y-axis;

[0010] The mathematical equation of the stator forming coil surface is established by using the fitting method of numerical iterative optimization of the least square adjustment method.

[0011] Finally, the normal vector of the coil surface point, the total length of the coil, the outer span and the nose height are calculated;

[0012] The total length of the coil is calculated as follows:

[0013] Select two points with the maximum and minimum values ​​on the x-axis, and the distance between the two points is the total length of the coil;

[0014] The outer span is calculated as:

[0015] Select the two points with the maximum value on the y-axis to determine the first straight line, select the two points with the minimum value on the y-axis to determine the second straight line, and calculate the distance between the first straight line and the second straight line, which is the outer span;

[0016] The nose height is calculated as follows:

[0017] Select the three points with the minimum z-axis value to determine a plane, select the point with the maximum z-axis value, and calculate the distance from the point to the plane, which is the nose height.

[0018] Furthermore, point cloud preprocessing includes cleaning and filtering point cloud data, reconstructing geometric surfaces, filling defects, and smoothing.

[0019] Furthermore, the mathematical equation of the stator forming coil surface is as follows:

[0020] z=k0+k 10 x+k 11 y+k 20 x 2 +k 21 xy+k 22 y 2 +…+k n0 x n +k n1 x n-1 y+…+k nn y n

[0021] In the formula, x, y and z are coordinates, n is the degree, k0, k 10 to k nn are the parameters to be fitted.

[0022] Furthermore, the normal vector calculation method of the coil surface point is:

[0023] Select any point cloud data point P, obtain a set of n neighboring data points, and calculate the center point of the set of neighboring data points in, and is the coordinate of the center point;

[0024] Construct the matrix C:

[0025]

[0026] In the formula, x n ,y n and z n Represents the coordinates of the nth point in the set of neighboring data points;

[0027] Then the covariance matrix of the data point set is:

[0028] N=C T C

[0029]

[0030] Among them, λ i is the i-th characteristic coefficient of the covariance matrix N, V i is the i-th eigenvector; the correlation between the normal vector perpendicular to the feature plane is the smallest, then the eigenvector corresponding to the minimum eigenvalue coefficient is the normal vector of the data point P.

[0031] Furthermore, the total length of the coil is calculated as follows:

[0032] Select the point with the maximum value on the x-axis (X imax ,Y s ,Z s ) and the point with the minimum x-axis value (X imin ,Y q ,Z q );

[0033] Calculate the total length of the coil using the Euclidean distance calculation formula:

[0034]

[0035] Where D1 is the total length of the coil, X imax , Y s and Z s is the coordinate of the point with the maximum value on the x-axis, X imin , Yq and Z q The coordinates of the point with the minimum x-axis value.

[0036] Furthermore, the outer span calculation method is specifically as follows:

[0037] Select two points with the maximum value in the y direction and Among them, y max is the maximum y coordinate in the point cloud, and as well as and are the corresponding point coordinates;

[0038] Select two points with the minimum value in the y direction and Among them, y min is the minimum y coordinate in the point cloud, and as well as and are the corresponding point coordinates;

[0039] Determine the straight edge l1 through points P and Q, and determine the straight edge l2 through points R and S:

[0040] l1:

[0041] l2:

[0042]

[0043] In the formula, A i ,B i and C i is the coefficient, i=1,2,3,4; Δ is the value of the coefficient determinant;

[0044] The outer span is:

[0045] Among them, n i =(A i ,B i ,C i ),i=1,2,3,4.

[0046] Furthermore, the nose height calculation method is specifically as follows:

[0047] Select two points with the maximum value in the y direction and the minimum value in the z direction and Among them, y max is the maximum y coordinate in the point cloud, z min is the minimum z coordinate in the point cloud, and is the corresponding x coordinate;

[0048] Select a point with the minimum value in the y direction and the minimum value in the z direction Among them, y min is the minimum y coordinate in the point cloud, z min is the minimum z coordinate in the point cloud, is the corresponding x coordinate;

[0049] Substitute the coordinates of these three points into the plane equation and solve them simultaneously:

[0050]

[0051] In the formula, A, B, C and D are coefficients, x i ,y i and z i is the coordinate of the i-th point, i = 1, 2 and 3;

[0052] Select the point with the maximum value on the Z axis in the point cloud data (x u ,y u ,z umax ), then the nose height is:

[0053]

[0054] Where D3 is the height of the nose.

[0055] Further, it is determined whether the total coil length, outer side span and nose height are within the qualified range.

[0056] An electronic device, comprising:

[0057] a memory for storing executable computer programs;

[0058] The processor is used to implement any one of the above-mentioned methods for calculating the size of the stator forming coil of the permanent magnet traction motor based on three-dimensional scanning when executing the executable computer program stored in the memory.

[0059] A computer-readable storage medium stores a computer program for implementing any one of the above-mentioned methods for calculating the size of a permanent magnet traction motor stator forming coil based on three-dimensional scanning when executed by a processor.

[0060] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0061] 3D scanning point cloud modeling technology is suitable for measuring objects with complex geometric shapes. Point cloud modeling can provide a large amount of discrete point data, and can obtain a large amount of quantitative data of stator forming coils, which improves the accuracy and repeatability of measurement, thereby accurately reflecting the shape and curvature of the coils. The key dimension calculation method based on 3D scanning point cloud modeling technology can provide more comprehensive and detailed data for subsequent coil geometry analysis, including coil shape, size, surface curvature, normal vector and other attributes, which facilitates the rapid size detection of stator forming coils, saves time and cost, and provides an innovative method for measuring dimensions for the stator forming coil intelligent manufacturing production line, which has good reference value. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 The block diagram of the method for calculating the size of the stator forming coil of the permanent magnet traction motor based on three-dimensional scanning;

[0063] Figure 2 This is a schematic diagram of the 3D scanning point cloud model of the stator forming coil;

[0064] Figure 3 This is a simplified processing diagram of the stator forming coil model;

[0065] Figure 4 It is a schematic diagram of the structure of the stator forming coil;

[0066] Figure 5 This is a schematic diagram of the normal vector of the stator forming coil point cloud;

[0067] Figure 6 This is a schematic diagram of measuring the total length of the stator forming coil;

[0068] Figure 7 This is a schematic diagram of the span measurement of the stator forming coil;

[0069] Figure 8 Schematic diagram of the stator forming coil nose height measurement. DETAILED DESCRIPTION

[0070] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0071] The present invention discloses a method for calculating the key dimensions of a stator forming coil based on three-dimensional scanning technology, in order to solve the problem that the key dimensions of a permanent magnet traction motor stator forming coil with complex curved surface features are difficult to measure accurately. The specific steps are: first, initially configure a three-dimensional scanner to collect point cloud data of the stator forming coil to obtain a point cloud model of the stator forming coil, simplify the model and reduce data noise through data processing to obtain a stator forming coil fitting mathematical model, establish a three-dimensional coordinate system, determine the fitting accuracy by calculating the determination coefficient, and then calculate and measure the key dimensions, including feature point normal vector calculation, coil total length measurement, outer span measurement, and nose height measurement. Then, the results are analyzed, and according to the calculation results of the key dimension data, the total length measurement value of the coil, the outer span measurement value, and the nose height measurement value are analyzed, and point cloud data analysis and processing are performed to achieve fast and accurate inspection of the stator forming coils of permanent magnet traction motors of different models and sizes to see whether the coils meet the quality requirements.

[0072] Example 1

[0073] The present invention provides a method for calculating the key dimensions of a permanent magnet traction motor stator forming coil based on three-dimensional scanning technology. Figure 1 As shown, the following steps are included:

[0074] S1: Initial Configuration

[0075] First, prepare a 3D scanner and a computer. The scanner can be selected according to the shape and size of the permanent magnet traction motor stator forming coil. The computer needs to be installed with the corresponding 3D scanning point cloud modeling software.

[0076] S2: Collecting point cloud

[0077] Fix the 3D scanner around the permanent magnet traction motor stator coil, keep a fixed distance and angle, and start the scanner. The scanner projects light spots through laser or structured light, and the scanner generates 3D point cloud data of the permanent magnet traction motor stator coil by collecting the reflected light spots, such as Figure 2 shown.

[0078] S3: Data Processing

[0079] The acquired 3D point cloud data is imported into the computer, and the corresponding 3D scanning point cloud modeling software is used to pre-process the data, including cleaning and filtering point cloud data, reconstructing geometric surfaces, filling defects, smoothing and other operations to generate a continuous 3D model.

[0080] S4: Measuring key dimensions and calculations

[0081] Use the measurement tools in the 3D scanning point cloud modeling software to measure the key dimensions of the permanent magnet traction motor stator formed coil, including coil size, shape, curvature and other parameters. For complex surfaces and curvatures, the curvature calculation tool in the software can be used for accurate calculations.

[0082] S5: Results Analysis

[0083] The measured and calculated data are compared and verified with the set process procedures or the criteria required by the quality process tracking card to determine whether the measured value is within the qualified range. The result can be obtained, that is, whether the workpiece is allowed to flow into the next process.

[0084] In this embodiment, the specific steps of step S3 are:

[0085] S31: Simplified model. Figure 3 As shown in the figure, the model of the scanned stator forming coil model is simplified. The connecting leads are mainly used to connect the two ends in parallel, and are usually not used as key size and quality control points of the coil. This time, the connecting leads are smoothly trimmed to complete the discrete point cloud surface reconstruction, and the normal vector of any point in the forming coil model point cloud is solved.

[0086] S32: Obtain the mathematical model of the stator forming coil shape. Use the fitting method of the least squares adjustment numerical iteration optimization to establish the mathematical equation of the stator forming coil surface. That is, fit the stator forming coil nose surface through the scanned point cloud data to minimize the sum of the squares of the difference between the surface and the point cloud data. i ,y i ,z i ) between the multi-term equations (the coefficients are real numbers, and the coefficients of the multi-terms are not all zero), the equation is as follows:

[0087] z=k0+k1x+k2y+k3x 2 +k4xy+k5y 2 +…+k n x n +k n+1 x n-1 y+…+k n+2 y n

[0088] Among them, k0, k 10 to k nn are the required fitting parameters, x and y represent the horizontal and vertical coordinates of the selected point respectively, and z represents the height coordinate of the point.

[0089] The characteristic point cloud of the stator forming coil surface is fitted in the form of a polynomial. The polynomial method is selected to fit the surface. When fitting the surface, it is necessary to ensure that the surface has a high fitting accuracy and at the same time simplify the model accordingly to facilitate design and manufacturing.

[0090] S33: Calculate the coefficient of determination R 2 The accuracy of the coil fitting is characterized by the change in data.

[0091]

[0092] In the formula, y i represents the actual observed value, represents the predicted value, represents the true observed value.

[0093] In this embodiment, the specific steps of step S4 are:

[0094] S41: Calculation of feature point normal vector

[0095] The calculation of the normal vector of the feature point plays an important role in describing the surface features of geometric objects. When calculating the key dimensional parameters of the stator forming coil, it is necessary to calculate the normal vector of the coil surface. By analyzing the normal vector of the plane, the distance between the point and the plane can be obtained, and the distance between the nose bending vertex and the placement plane, that is, the nose height, can be obtained. The point cloud within a certain range of the feature point is fitted with a surface, and the normal vector of the feature point is obtained based on the fitting, such as Figure 5 shown.

[0096] Select any point cloud data point P and obtain n neighboring data points. Assume that the center point of the neighboring set is The plane passing through point P is obtained by fitting method, and the expression is as follows:

[0097]

[0098] ax+by+cz-d=0

[0099] Combining the above two equations, we get:

[0100]

[0101] The transformation into matrix is ​​represented as:

[0102]

[0103] In the above matrix, n is the number of adjacent data sets, so the covariance matrix of the data set is:

[0104] N=C T C

[0105]

[0106] Among them, λ i is the i-th characteristic coefficient of the covariance matrix N, V i is the i-th eigenvector. The correlation between the normal vector perpendicular to the eigenplane is the smallest, and the eigenvector corresponding to the minimum eigencoefficient is the normal vector of the fitting surface.

[0107] S42: Coil total length D1 measurement method

[0108] The point cloud data set selection rule is to filter out the stator forming coil point cloud data set X imin and X imax The two coordinate points of the coil are clearly defined as the total length D1 of the coil, which is the right end point of the maximum value of the X axis (X imax ,Y s ,Z s ) and the minimum X-axis value (X imin ,Y q ,Z q ) can be calculated by the Euclidean distance formula to obtain the total length of the coil:

[0109]

[0110] like Figure 6 As shown, D1 is the total length of the coil.

[0111] S43: Measurement method of outer span D2

[0112] The measurement method of the stator forming coil outer span D2 is calculated by the maximum distance between the outer sides of the two straight lines, and then converted into the distance between two non-planar straight lines. Figure 4 and Figure 7 As shown, the lower edge of the two outer layers is the minimum distance, and the upper edge is the maximum distance. Select two straight line functions of the upper edges of the two layers as the benchmark, and their spacing is the outer span D2. Find the straight line edge formulas of the lower edge and the upper edge of the two outer layers, respectively, l1 and l2, and find the distance between the straight lines in the two layers, then their spacing is the outer span D2.

[0113] The span of the stator forming coil point cloud data set is obtained by the edge lines of the upper layer of the two outer layers, and the distance between the two edge lines is the outer span. Select two points P (x1, y1, z1) and Q (x2, y2, z2) on one of the edge lines. The selection rule of P is that the x-axis is flush with the outer layer side surface, and the maximum value |y is selected in the y direction. max |, select any number in the x-axis and z-axis directions Sure and Point; determine the straight line l1 through points P and Q. Determine the rule for selecting the two points on the other side as the minimum value |y in the y direction min |, select any number in the x-axis and z-axis directions Determine the straight edge l2 through points R and S.

[0114] l1:

[0115] l2:

[0116]

[0117] Then the spacing is the outer span D2:

[0118]

[0119] Among them, n i =(A i ,B i ,C i ),i=1,2,3,4.

[0120] S44: Nose height D3 measurement method

[0121] In the actual measurement process, the nose height is mainly obtained by placing the coil on a plane and measuring the distance between the nose bending vertex and the placement plane. Figure 8 As shown, the nose height D3 is measured by placing the coil on a plane defined by the lower outer edges of the two straight sides. The distance between the vertex of the nose curve and the placement plane is measured and converted into the vertical straight line distance between the plane defined by the lower layer edges of the two outer spans of the coil and the vertex of the nose curve.

[0122] The method for measuring nose height is:

[0123] In the point cloud data, three data points V1 (x1, y1, z1), V2 (x2, y2, z2) and V3 (x3, y3, z3) are selected on the lower edges of two straight lines. These three-dimensional points constitute the characteristics of the plane. The equation of the plane is fitted using the principle of least squares method to determine the plane V to be obtained.

[0124] The selection rule of P is to select the maximum value in the y direction |y max | and the minimum value in the z direction |z min |, select any number on the x-axis Sure and point; select the minimum value in the y direction |y min| and the minimum value in the z direction |z min |, OK

[0125] Substitute the three data points into the plane equation and solve them simultaneously, as shown below:

[0126]

[0127] Select the maximum value (x u ,y u ,z umax ), the general equation of the plane is shown in the formula, then the equation of the transformed plane is:

[0128]

[0129] Transformed into matrix form:

[0130]

[0131] The response value can be obtained by finding the matrix expression of a0, a1, and a2, and the equation of the placement plane where the coil is located can be obtained. Then, the distance from the vertex of the coil to the placement plane can be used to calculate the distance from the feature point to the placement plane, which is D3, and this distance is the coil nose height size:

[0132]

[0133] According to the calculation results of the key dimension data, the S42 coil total length D1 measurement value, S43 outer span D2 measurement value, S44 nose height D3 measurement value are analyzed, and point cloud data analysis and further processing are performed. By comparing the measured data with the design parameters, it can be checked whether the coil meets the requirements.

[0134] Example 2

[0135] A method for calculating the key dimensions of a permanent magnet traction motor stator forming coil based on 3D scanning technology includes 5 steps, including initial configuration, point cloud acquisition, data processing, key dimension measurement and calculation, and result analysis. It can achieve 3 key dimension measurements, namely, the total length, outer span, and nose height of the stator forming coil. This method is not limited to measuring only 3 key dimension parameters.

[0136] The initial configuration is to prepare a 3D scanner and a computer. The scanner can be selected according to the shape and size of the permanent magnet traction motor stator forming coil. The computer needs to be installed with the corresponding 3D scanning point cloud modeling software.

[0137] Arrange the scanner and scan, install the 3D scanner around the permanent magnet traction motor stator forming coil, keep a fixed distance and angle, and start the scanner. The scanner will project light spots through laser or structured light, and the scanner will generate 3D point cloud data of the permanent magnet traction motor stator forming coil by collecting the reflected light spots.

[0138] Data processing is to import the acquired 3D point cloud data into the computer and use the corresponding 3D scanning point cloud modeling software to process the data. It includes operations such as cleaning and filtering point cloud data, reconstructing geometric surfaces, filling defects, and smoothing to generate a continuous 3D model.

[0139] Measuring key dimensions and calculations is done by using the measurement tools in the 3D scanning point cloud modeling software to measure the key dimensions of the stator forming coils of the permanent magnet traction motor, including coil size, shape, curvature and other parameters. For complex surfaces and curvatures, the curvature calculation tool in the software can be used for accurate calculations.

[0140] The result analysis is to simplify the model in the scanned stator forming coil model. The connecting leads are mainly used to connect the two ends in parallel, which is usually not used as the key size and quality control point of the coil. This time, the connecting leads are smoothly cut off. The formed triangle pieces are optimized, the discrete point cloud surface reconstruction is completed, and the normal vector of any point in the forming coil model point cloud is solved.

[0141] The characteristic point cloud of the stator forming coil surface is fitted in the form of a polynomial. The polynomial method is selected to fit the surface. When fitting the surface, it is necessary to ensure that the surface has a high fitting accuracy and simplify the model accordingly to facilitate design and manufacturing. Determination coefficient R 2 The accuracy of the coil fitting is characterized by the change in data. The normal value range is [0, 1]. The closer it is to 1, the stronger the explanatory power of the variables in the fitting equation for y and the higher the fitting accuracy.

[0142] The statistical stator forming coil parameter calculation is the sum of squares of the errors between the fitting data and the corresponding points of the original data. The calculation formula is as follows:

[0143]

[0144]

[0145] This statistical parameter is the mean of the sum of squares of the corresponding point errors between the predicted data and the original data. The calculation formula is as follows:

[0146]

[0147]

[0148]

[0149] The calculation of the normal vector of the feature point plays an important role in describing the surface features of geometric objects. When calculating the key dimensional parameters of the stator forming coil, it is necessary to calculate the normal vector of the coil surface. By analyzing the normal vector of the plane, the distance between the point and the plane can be obtained, and the distance between the nose bending vertex and the placement plane, that is, the nose height, can be obtained. The point cloud within a certain range of the feature point is fitted with a surface, and the normal vector of the feature point is obtained based on the fitting.

[0150] Finally, based on the calculation results of the key dimension data, the total length D1 measurement of the coil, the outer span D2 measurement, and the nose height D3 measurement are analyzed, and the point cloud data is analyzed and further processed. By comparing the measured data with the design parameters, it can be checked whether the coil meets the requirements.

[0151] Example 3

[0152] The present invention also provides an electronic device, comprising:

[0153] a memory for storing executable computer programs;

[0154] The processor is used to implement any one of the above-mentioned methods for calculating the size of the stator forming coil of the permanent magnet traction motor based on three-dimensional scanning when executing the executable computer program stored in the memory.

[0155] Example 4

[0156] The present invention also provides a computer-readable storage medium storing a computer program for implementing any one of the above-mentioned methods for calculating the size of a permanent magnet traction motor stator forming coil based on three-dimensional scanning when executed by a processor.

[0157] In summary, the present invention proposes a method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning, which can obtain a large amount of quantitative data of the stator forming coil, improve the measurement accuracy and repeatability, and thus accurately reflect the shape and curvature of the coil. The key dimension calculation method based on the three-dimensional scanning point cloud modeling technology can provide more comprehensive and detailed data for the subsequent coil geometry analysis, including the shape, size, surface curvature, normal vector and other attributes of the coil, facilitate the rapid size detection of the stator forming coil, save time and cost, and provide an innovative method for measuring the size of the stator forming coil intelligent manufacturing production line, which has good reference value.

[0158] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0159] It will be easily understood by those skilled in the art that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calculating the size of a permanent magnet traction motor stator forming coil based on three-dimensional scanning, characterized in that: The method includes: Obtain the three-dimensional point cloud data of the permanent magnet traction motor stator formed coil and perform point cloud preprocessing; Smoothly cut the connection lead wire part of the permanent magnet traction motor stator forming coil in the three-dimensional point cloud data; A rectangular coordinate system is established with the main direction of the permanent magnet traction motor stator forming coil as the x-axis and the direction perpendicular to the x-axis in the plane where the permanent magnet traction motor stator forming coil is located as the y-axis; The mathematical equation of the stator forming coil surface is established by using the fitting method of numerical iterative optimization of the least square adjustment method. Finally, the normal vector of the coil surface point, the total length of the coil, the outer span and the nose height are calculated; The total length of the coil is calculated as follows: Select two points with the maximum and minimum values ​​on the x-axis, and the distance between the two points is the total length of the coil; The outer span is calculated as: Select the two points with the maximum value on the y-axis to determine the first straight line, select the two points with the minimum value on the y-axis to determine the second straight line, and calculate the distance between the first straight line and the second straight line, which is the outer span; The nose height is calculated as follows: Select the three points with the minimum z-axis value to determine a plane, select the point with the maximum z-axis value, and calculate the distance from the point to the plane, which is the nose height; Among them, the mathematical equation of the stator forming coil surface is as follows: z=k0+k 10 x+k 11 y+k 20 x 2 +k 21 xy+k 22 y 2 +…+k n0 x n +k n1 x n-1 y+…+k nn y n In the formula, x, y and z are coordinates, n is the degree, k0, k 10 to k nn is the parameter to be fitted; The specific calculation method of the outer span is: Select two points with the maximum value in the y direction and Among them, y max is the maximum y coordinate in the point cloud, and as well as and are the corresponding point coordinates; Select two points with the minimum value in the y direction and Among them, y min is the minimum y coordinate in the point cloud, and as well as and are the corresponding point coordinates; Determine the straight edge l1 through points P and Q, and determine the straight edge l2 through points R and S: In the formula, A i ,B i and C i is the coefficient, i=1,2,3,4; Δ is the value of the coefficient determinant; The outer span is: Among them, n i =(A i ,B i ,C i ),i=1,2,3,4.

2. The method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning according to claim 1 is characterized in that: Point cloud preprocessing includes cleaning and filtering point cloud data, reconstructing geometric surfaces, filling defects, and smoothing.

3. The method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning according to claim 1 is characterized in that: The normal vector calculation method of the coil surface point is: Select any point cloud data point P, obtain a set of n neighboring data points, and calculate the center point of the set of neighboring data points in, and is the coordinate of the center point; Construct the matrix C: In the formula, x n ,y n and z n Represents the coordinates of the nth point in the set of neighboring data points; Then the covariance matrix of the data point set is: N=C T C Among them, λ i is the i-th characteristic coefficient of the covariance matrix N, V i is the i-th eigenvector; the correlation between the normal vector perpendicular to the feature plane is the smallest, then the eigenvector corresponding to the minimum eigenvalue coefficient is the normal vector of the data point P.

4. The method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning according to claim 1 is characterized in that: The total length of the coil is calculated as follows: Select the point with the maximum value on the x-axis (X imax ,Y s ,Z s ) and the point with the minimum x-axis value (X imin ,Y q ,Z q ); Calculate the total length of the coil using the Euclidean distance calculation formula: Where D1 is the total length of the coil, X imax , Y s and Z s is the coordinate of the point with the maximum value on the x-axis, X imin , Y q and Z q The coordinates of the point with the minimum x-axis value.

5. The method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning according to claim 1 is characterized in that: The specific method for calculating nose height is: Select two points with the maximum value in the y direction and the minimum value in the z direction and Among them, y max is the maximum y coordinate in the point cloud, z min is the minimum z coordinate in the point cloud, and is the corresponding x coordinate; Select a point with the minimum value in the y direction and the minimum value in the z direction Among them, y min is the minimum y coordinate in the point cloud, z min is the minimum z coordinate in the point cloud, is the corresponding x coordinate; Substitute the coordinates of these three points into the plane equation and solve them simultaneously: In the formula, A, B, C and D are coefficients, x i ,y i and z i is the coordinate of the i-th point, i = 1, 2 and 3; Select the point with the maximum value on the Z axis in the point cloud data (x u ,y u ,z umax ), then the nose height is: Where D3 is the height of the nose.

6. The method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning according to claim 1 is characterized in that: Determine whether the total coil length, outer span and nose height are within the acceptable range.

7. An electronic device, characterized in that: include: a memory for storing executable computer programs; A processor is used to implement the method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning as described in any one of claims 1 to 6 when executing an executable computer program stored in a memory.

8. A computer-readable storage medium, characterized in that: A computer program is stored, which is used to implement the method for calculating the size of the stator forming coil of a permanent magnet traction motor based on three-dimensional scanning as described in any one of claims 1 to 6 when executed by a processor.

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