Device and method for variable-control grinding and polishing of stress conical surface of high-voltage cable based on least square method fitting measurement variable

Abstract

The invention discloses a device and a method for variable-control grinding and polishing of a stress conical surface of a high-voltage cable based on a least square method fitting measurement variable. The device comprises a three-dimensional measurement camera, a control system, a movement mechanism, a grinding and polishing tool, a TOF (Time of Flight) laser measurement module and a six-dimensional force sensor module, according to the method, when a cable joint is manufactured on site, the removal allowance of a lap joint transition area knife mark and a knife mark connecting area on a stress conical surface subjected to current grinding and polishing machining can be measured, corrected, compared and calculated in real time compared with an ideal model S0; and then the real-time feedback control system adjusts the force compensation and the pressing amount of the grinding tool according to the removal allowance calculated in real time, controllable allowance grinding and polishing machining on the transition area knife lines and connecting knife marks is achieved, and it can be further guaranteed that a smooth transition conical surface close to an ideal cone model S0 is ground and polished.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-voltage cable joint preprocessing, and in particular to a device and method for controlled grinding and polishing of a high-voltage cable stress cone surface based on least square fitting of measurement variables. BACKGROUND

[0002] With the continuous upgrading of power infrastructure in China, high-voltage, high-capacity power transmission and transformation components bear the task of ultra-long-distance power transmission, among which high-voltage cable joints are the core components of cable lines, bearing the electrical connection between cables and other equipment, and are related to the efficient and safe transmission of electric energy. If a high-voltage cable is damaged during service, the damaged area needs to be removed on site and a new cable joint needs to be made to connect the high-voltage cable. The quality of the cable joint directly affects the safe and stable operation of the power station. During the production of high-voltage cable joints, the insulating shielding layer of the high-voltage cable needs to be removed in a specific direction. During the removal process, problems such as uneven distribution of the radial thickness allowance of the cylindrical high-voltage cable covering layer, poor cable rigidity and easy bending need to be overcome to avoid steps, pits, dogtooth edges and burrs in the local area after removal. Therefore, the insulating shielding layer cannot be removed by rotating in a whole circle, but only in the form of a stress cone chamfer, which causes obvious knife marks and joint marks on the stress cone surface after removal. In order to ensure efficient and safe power transmission after the newly connected cable joint, the stress cone surface and the transition area of the cable insulating layer need to be smoothly transitioned to ensure the connection between the cable joint and the cable and low-loss power transmission. SUMMARY

[0003] The present application aims to overcome the above-mentioned deficiencies and provide a device and method for controlled grinding and polishing of a high-voltage cable stress cone surface based on least square fitting of measurement variables to solve the problems raised in the background art.

[0004] To solve the above technical problems, the technical solution adopted by the present application is: a device for controlled grinding and polishing of a high-voltage cable stress cone surface based on least square fitting of measurement variables, comprising a three-dimensional measurement camera, a control system, a motion mechanism, a grinding tool, a TOF laser measurement module and a six-axis force sensor module. The three-dimensional measurement camera is suspended at a distance h in the axial direction of the top end of the cable stress cone, and is used to measure the spatial coordinate data of the profile points of the knife marks and joint marks on the high-voltage cable stress cone surface. The TOF laser measurement module is integrated with the grinding tool and is used to measure the spatial distance data of the stress cone surface of the grinding area in real time. The six-axis force sensor module is connected with the grinding tool and is used to adjust the force compensation and the amount of pressure of the grinding tool. The motion mechanism is used to drive the polishing tool to move in the circumferential direction and to lift in the Z-axis direction; The control system is electrically connected with the three-dimensional measurement camera, the motion mechanism, the polishing tool, the TOF laser measurement module and the six-dimensional force sensor module respectively, and is used for receiving data, fitting calculation and issuing control instructions.

[0005] Preferably, the motion mechanism comprises a servo motor, a Z-axis module, a Y-axis module and a pitch axis module; the servo motor is used to drive the polishing tool to move in the circumferential direction of the annular rack tool; the Z-axis module is used to drive the polishing tool to lift in the Z-axis direction; and the Y-axis module and the pitch axis module are used to adjust the pose of the polishing tool, so that the polishing working surface of the polishing tool is parallel to the circular cone generatrix of the ideal cone model S0.

[0006] Preferably, the polishing tool comprises a constant force polishing abrasive belt machine and an abrasive belt; the abrasive belt is a polishing working surface, and the constant force polishing abrasive belt machine adjusts the polishing force under the action of the six-dimensional force sensor module.

[0007] Preferably, the device further comprises a clamping locking tool; the clamping locking tool is used to install the device on the horizontal section and the vertical section high-voltage cable stress cone, and to clamp and lock around the cable.

[0008] Preferably, the data measured by the three-dimensional measurement camera is used to construct a stress cone point cloud model S1, the control system calculates an ideal cone model S0 based on the stress cone angle θ and the size L0 of the cone surface generatrix, and nests the ideal cone model S0 in the stress cone point cloud model S1 to mark the excess area.

[0009] In addition, the application also discloses a method for controlled polishing of a high-voltage cable stress cone surface based on least square fitting of measurement variables, which is applied to the device for controlled polishing of a high-voltage cable stress cone surface based on least square fitting of measurement variables and comprises the following steps: S1: measurement modeling stage: install the polishing device on the horizontal section and the vertical section high-voltage cable stress cone to clamp and lock around the cable, measure the high-voltage cable stress cone by the three-dimensional measurement camera suspended at a distance h in the axial direction of the top end of the cable stress cone, measure the spatial coordinate data of the profile points on the knife marks and the knife mark area of the cable joint stress cone surface, fit the relatively accurate profile curve, obtain the stress cone point cloud model S1 after processing, synchronously construct a spatial coordinate system with the stress cone top end surface conductor as the center, and calculate the ideal cone model S0 with the same cone surface generatrix size L0 and the bottom surface radius r0 based on the stress cone angle θ and the size L0 of the cone surface generatrix, as the comparison model of the stress cone model S1; after all the measurement modeling is completed, return to the control system, the control system nests the ideal cone model S0 in the stress cone model S1, and marks the overall and local excess area of the stress cone model S1; S2: Adjust the pose of the polishing tool according to the cone angle θ of the ideal cone model S0 before processing, so that the sand belt working surface is parallel to the model S0 cone generatrix, and simultaneously divide the model S0 into n segments of conical surfaces along the cone generatrix direction with △L0 as the segment generatrix length; S3: Segment processing stage: when polishing the conical surface with a segment length of △L0, first guide the motion mechanism with the adjusted pose of the polishing tool to polish from the starting point of the conical surface near the stress cone bottom along the circumferential direction of the conical surface, simultaneously measure the space distance data of the knife marks and the knife mark area profile points on the stress cone surface of the polishing area in real time based on the TOF laser measurement module integrated with the polishing tool, and control the system based on the least square method to fit the space distance data, fit the slope of the segmented stress cone conical surface and the cross-sectional circle set of the conical surface, correct the model data of the current segment of the stress cone model S1, and compare with the ideal cone model S0 to calculate the removal allowance of the knife mark and the knife mark area of the lapped transition area on the conical surface of the current segment, and adjust the force compensation and the amount of pressing of the polishing tool according to the real-time calculated removal allowance to polish the removal allowance of the whole circle area of the processed conical surface to the ideal cone model S0; S4: Segment position changing stage: after the current segment processing is completed, the polishing tool keeps moving along the circumferential direction of the conical surface, while the motion mechanism drives the polishing tool to lift along the Z-axis direction by △h height, and after lifting is completed, the next segment conical surface area of the stress cone is polished; S5: Repeat steps S3-S4 until the measured allowance of the knife mark and the knife mark area of the lapped transition area of the whole conical surface area of the high-voltage cable stress cone is polished and removed, and after the three-dimensional measurement camera measures and compares the ideal cone model S0, the whole polishing operation is completed.

[0010] Further, in step S2, the data of △L0 depends on the polishing working surface size of the polishing tool.

[0011] Further, in step S3, the specific process of fitting the space distance data based on the least square method is as follows: The stress cone point cloud model S1 is analyzed to obtain a sample set of the knife mark and the knife mark area profile points on the current segment stress cone conical surface (x i , y i ), i=1, 2, 3, …, N; The distance from the i-th sample profile point on the cross-sectional circle of the stress cone to the stress cone center is denoted as d i , then: ; The ideal cone model S0 is nested within the stress cone model S1. The i-th sample contour point (A) of the ideal cone model S0 i B i Then, the error between the radii of the fitted circles corresponding to the current two sample contour points is: ; Sample set (x) i y i The expressions for the error and Q(A,B) for i=1,2,3,...,N are: ; The spatial distance data of the i-th sample contour point measured by the TOF laser measurement module is D. i Correct the sample set error and Q(A,B) to a minimum, so that d i =D i ;Right now: .

[0012] Furthermore, in step S4, △h is calculated based on the data of the ideal cone model S0. The ideal cone model has a consistent slope, which can unify the slope offset during the n-segment transposition process along the generatrix of the stress cone from the bottom of the cone upwards during processing, and polish the transition area of ​​each segment of the cone surface of the stress cone to a smooth transition.

[0013] Furthermore, the formula for calculating Δh based on the data from the ideal cone model S0 is as follows: ; Where △h is the lifting height, △L0 is the segment generatrix length, r0 is the base radius, and n is the number of segments.

[0014] The beneficial effects of this invention are as follows: The method of this invention can correct the sample set error and Q(A,B) in real time and accurately by comparing the error (removal allowance) between the fitted circle sample set of real-time measured contour points and the radius of the cross-sectional circle of the stress cone model; and by comparing it with the ideal cone model S0, it can calculate the removal allowance of the tool marks and tool joint marks in the overlapping transition area of ​​the cone surface being ground and polished compared with the ideal model S0; then, the real-time feedback control system adjusts the force compensation and downward pressure of the grinding tool according to the real-time calculated removal allowance, so as to realize the controllable allowance grinding and polishing of the tool marks and tool joint marks in the transition area, and further ensure that the grinding and polishing produces a cone surface with a smooth transition close to the ideal cone model S0. Attached Figure Description

[0015] Figure 1 This is a three-dimensional schematic diagram of the processing layout described in this invention; Figure 2 This is a top view of the processing layout described in this invention; Figure 3 is a schematic diagram of the motion mechanism and the polishing tool structure according to the present application; Figure 4 is a schematic diagram of the method principle according to the present application; In the figure, 1 is a three-dimensional measurement camera; 2 is a high-voltage cable stress cone; 3 is a clamping locking tool; 4 is an annular rack tool; 5 is a motion mechanism; 51 is a servo motor; 52 is a Z-axis module; 53 is a Y-axis module; 54 is a pitch axis module; 6 is a TOF laser measurement module; 7 is a six-dimensional force sensor module; 8 is a polishing tool; 81 is a constant force polishing abrasive belt machine; and 82 is an abrasive belt. DETAILED DESCRIPTION

[0016] The present application will be further described in detail below in combination with the drawings and specific embodiments.

[0017] Embodiment 1: A device for controlling the polishing of a high-voltage cable stress cone surface based on least square fitting of measurement variables, comprising a three-dimensional measurement camera, a control system, a motion mechanism, a polishing tool, a TOF laser measurement module, and a six-dimensional force sensor module. The three-dimensional measurement camera is suspended at a distance h in the axial direction of the top end of the cable stress cone, and is used to measure the spatial coordinate data of the profile points of the knife marks and the knife mark areas on the surface of the high-voltage cable stress cone. The TOF laser measurement module is integrated with the polishing tool, and is used to measure the spatial distance data of the polishing area in real time. The six-dimensional force sensor module is connected with the polishing tool, and is used to adjust the force compensation and the amount of pressing down of the polishing tool. The motion mechanism is used to drive the polishing tool to move in the circumferential direction and to lift in the Z-axis direction. The control system is electrically connected with the three-dimensional measurement camera, the motion mechanism, the polishing tool, the TOF laser measurement module, and the six-dimensional force sensor module, respectively, and is used to receive data, perform fitting calculation, and issue control instructions.

[0018] Preferably, the motion mechanism comprises a servo motor, a Z-axis module, a Y-axis module, and a pitch axis module; the servo motor is used to drive the polishing tool to move in the circumferential direction along the annular rack tool; the Z-axis module is used to drive the polishing tool to lift in the Z-axis direction; and the Y-axis module and the pitch axis module are used to adjust the pose of the polishing tool, so that the polishing working surface of the polishing tool is parallel to the generatrix of the ideal cone model S0.

[0019] Preferably, the polishing tool comprises a constant force polishing abrasive belt machine and an abrasive belt; the abrasive belt is the polishing working surface, and the constant force polishing abrasive belt machine adjusts the polishing force under the action of the six-dimensional force sensor module.

[0020] Preferably, a clamp locking tool is further included, which is used to mount the device on the high-voltage cable stress cone of the horizontal and vertical sections and clamp and lock around the cable.

[0021] Preferably, the data measured by the three-dimensional measurement camera is used to construct a stress cone point cloud model S1, the control system calculates an ideal cone model S0 based on the stress cone angle θ and the size L0 of the cone generatrix, and nests the ideal cone model S0 in the stress cone point cloud model S1 to mark the excess area.

[0022] Embodiment 2: A method for controlling the grinding and polishing of the high-voltage cable stress cone surface based on least squares fitting of measurement variables, applied to the device for controlling the grinding and polishing of the high-voltage cable stress cone surface based on least squares fitting of measurement variables, comprising the following steps: S1: Measurement modeling stage: install the grinding and polishing device on the high-voltage cable stress cone of the horizontal and vertical sections and clamp and lock around the cable, suspend the three-dimensional measurement camera along the axial direction h of the cable stress cone top end, measure the space coordinate data of the profile points on the cable joint stress cone surface, fit the more accurate profile curve, obtain the stress cone point cloud model S1 after processing, simultaneously construct a space coordinate system with the stress cone top end surface conductor as the center, and calculate the ideal cone model S0 with the same cone generatrix size L0 and bottom radius r0 based on the stress cone angle θ and the size L0 of the cone generatrix, as the comparison model of the stress cone model S1; after all the measurement modeling is completed, return to the control system, the control system nests the ideal cone model S0 in the stress cone model S1, and marks the overall and local excess area of the stress cone model S1; S2: Section adjustment stage: adjust the grinding and polishing tool pose according to the cone angle θ of the ideal cone model S0 before processing, so that the abrasive belt working surface is parallel to the model S0 cone generatrix, and simultaneously divide the model S0 into n sections along the cone generatrix direction with △L0 as the section generatrix length; S3: segment processing stage: when grinding and polishing the conical surface of the segmented bus length △L0, first guide the motion mechanism with the adjusted pose of the grinding and polishing tool from the stress cone to the conical surface near the cone bottom as the starting cutting point along the circumferential direction of the conical surface, and simultaneously measure the space distance data of the tool marks and the joint mark area profile points on the stress cone surface of the grinding area in real time according to the TOF laser measurement module integrated with the grinding and polishing tool, the synchronous control system fits the slope of the segmented stress cone conical surface and the cross section circle set of the conical surface based on the least square method, corrects the model data of the current segment corresponding to the stress cone model S1, and compares with the ideal cone model S0 to calculate the removal allowance of the tool marks and the joint mark area on the conical surface of the current segment grinding and polishing, and the feedback control system adjusts the force compensation and the amount of pressing of the grinding tool according to the real-time calculated removal allowance until the removal allowance of the whole grinding and polishing area of the processed conical surface is ground and polished to the ideal cone model S0; S4: segment position changing stage: after the current segment processing is completed, the grinding and polishing tool keeps moving along the circumferential direction of the conical surface, and the motion mechanism drives the grinding and polishing tool to lift along the Z-axis direction by △h height, and after lifting is completed, the grinding of the next segment conical surface area of the stress cone is started; S5: repeat steps S3-S4 until the measured allowance of the tool marks and the joint mark area of the whole conical surface area of the high-voltage cable stress cone is ground and polished, and after the three-dimensional measurement camera measures and compares the ideal cone model S0, the whole grinding and polishing operation is completed.

[0023] Further, in step S2, the data of △L0 depends on the grinding working surface size of the grinding and polishing tool.

[0024] Further, in step S3, the specific process of fitting the space distance data based on the least square method is as follows: The stress cone point cloud model S1 is analyzed to obtain the sample set of the tool marks and the joint mark area profile points on the current segment stress cone conical surface (x i , y i ), i=1, 2, 3, …, N; The distance from the i-th sample profile point on the cross section circle of the stress cone to the center of the stress cone is denoted as d i , then: ; The ideal cone model S0 is nested in the stress cone model S1, and the i-th sample profile point (A i , B i ) of the ideal cone model S0, then the error between the radii of the fitted circles corresponding to the two sample profile points is: ; A sample set (x i , y i ), i = 1, 2, 3, …, N, and the expression of error sum Q (A, B) is: ; The spatial distance data of the i-th sample profile point measured by the TOF laser measurement module is D i , and the sample set error sum Q (A, B) is corrected to be minimized, so that d i =D i ; that is: .

[0025] Further, in step S4, △h is calculated based on the data of the ideal cone model S0. The slope of the ideal cone model is consistent, and the slope offset can be unified in the n-section transposition process from the bottom of the cone to the upper part along the stress cone generatrix. The transition area of each segmented conical surface of the stress cone surface is polished to smooth transition.

[0026] Further, the formula for calculating △h based on the data of the ideal cone model S0 is as follows: ; Where △h is the lifting height, △L0 is the length of the segmented generatrix, r0 is the radius of the base, and n is the number of segments.

[0027] Embodiment 3: as shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 , this embodiment provides a device and method for controlling the amount of polishing of the stress cone surface of high-voltage cable based on least squares fitting of measurement variables. The entire implementation technical scheme for the controlled allowance polishing process of the knife marks and knife marks in the transition area of the stress cone surface of the high-voltage cable covered with an insulating shielding layer includes the following aspects.

[0028] After the insulating shielding layer of the high-voltage cable is stripped to make a stress cone joint, the stress cone surface needs to be polished; for example Figure 1 , Figure 2 , Figure 4As shown, before processing, the high-voltage cable is fixed and adjusted by the clamping locking tool 3, and then the three-dimensional measurement camera 1 suspended at a distance h in the axial direction of the top end of the cable stress cone measures the high-voltage cable stress cone 2, measures the space coordinate data of the profile points of the knife marks and the knife mark areas on the stress cone surface of the cable joint, fits a relatively accurate profile curve, and obtains a stress cone point cloud model S1 after processing. A space coordinate system with the stress cone top end surface conductor as the center is constructed synchronously, and an ideal cone body model S0 with the same size of the generatrix and the bottom surface radius r0 is calculated according to the stress cone angle θ and the size L0 of the cone surface generatrix, which is used as the comparison model of the stress cone model S1. After all the measurement and modeling are completed, they are returned to the control system, the control system nests the ideal cone body model S0 in the stress cone model S1, and marks the overall and local excess area of the stress cone model S1; As shown in Figure 3 , Figure 4 , the Y-axis module 53 and the pitch axis module 54 are adjusted according to the ideal cone body model S0, so that the working surface of the constant force grinding and polishing belt machine 81 is parallel to the ideal model S0 cone generatrix, and the model S0 is equally divided into multiple conical surfaces along the cone generatrix direction with △L0 (△L0 data depends on the polishing working surface size of the polishing tool) as the segmented generatrix length; During segmented processing, as shown in Figure 1 , Figure 3 , Figure 4 , the position is searched according to the model segmented conical surface data, the grinding and polishing tool 8 with adjusted pose is guided by the Z-axis module to move from the conical surface close to the bottom of the high-voltage cable stress cone 2 as the starting cutting point, the servo motor 51 drives the lower ring gear tool 4 to move, that is, the grinding and polishing tool 8 starts to polish along the circumferential direction of the segmented conical surface while maintaining the pose. During the processing, the TOF laser measurement module 6 integrated with the grinding and polishing tool measures the stress cone conical surface space distance data of the polishing area in real time, the least square method is used to fit the space distance data based on the synchronous control system, the slope of the segmented stress cone conical surface and the cross-sectional circle set of the conical surface of the current grinding and polishing processing are fitted, the stress cone model S1 corresponding to the current segment is corrected, and compared with the ideal cone body model S0. The control system calculates the removal allowance of the lap joint transition area knife mark and the knife mark area on the conical surface of the current segmented grinding and polishing processing, and adjusts the force compensation and the amount of pressing applied to the constant force grinding and polishing belt machine 81 in real time according to the real-time calculation of the removal allowance through the six-dimensional force sensor module 7 until the removal allowance of the whole circle area of the processed conical surface is polished to the corresponding ideal cone body model S0. The stress cone point cloud model S1 is analyzed to obtain a sample set (x i , y i ) of the profile points of the knife mark and the knife mark area on the current segmented stress cone conical surface, i=1,2,3,……,N; The distance from the i-th sample profile point on the cross-section circle of the stress cone to the center of the stress cone is denoted as d i , then ; The ideal cone model S0 is nested in the stress cone model S1, and the error (excluding the allowance) between the radii of the fitting circles corresponding to the i-th sample profile point (A i , B i ) of the ideal cone model S0 is: ; The error sum Q(A, B) of the sample set (x i , y i ) i=1, 2, 3, …, N is expressed as: ; The spatial distance data of the i-th sample profile point measured by the TOF laser measurement module is D i , and the sample set error sum Q(A, B) is corrected to be minimized, so that d i =D i ; that is: ; Combined with the sample data D i measured by the TOF laser measurement module 6 in real time during the grinding and polishing process, the sample set error sum Q(A, B) is corrected to be minimized, and the cross-section circle set of the i-th sample profile point currently located on the segmented stress cone conical surface is fitted out in synchronization. Combined with the comparison with the ideal cone model S0, the removal allowance of the lap joint transition area tool marks and the tool marks area on the conical surface of the current segmented grinding and polishing process compared with the ideal model S0 is calculated; the control system feeds back the removal allowance calculated in real time to the six-dimensional force sensor module 7 to adjust the force compensation and the amount of pressing applied to the constant force grinding and polishing belt machine 81 in real time until the removal allowance of the entire area of the conical surface processed is ground and polished to correspond to the ideal cone model S0.

[0029] After the segmented processing is completed, the grinding tool 8 remains moving in the circumferential direction while the movement mechanism 5 is lifted by a height of △h (the lifting height , the lifting height is calculated based on the data of the ideal cone model S0, and the ideal cone model has a consistent slope, which can unify the slope offset as much as possible during the n-segment displacement process along the stress cone generatrix from the bottom of the cone upward, and grind and polish the transition areas of the segmented conical surfaces of the stress cone to smooth transition), and after the lifting is completed, the next segmented conical surface area of the stress cone is polished.

[0030] The above method is sequentially processed until the stress cone is all tapered surface area allowance polishing processing to close to the ideal cone model S0. Finally, the profile curve of the high-voltage cable stress cone is fitted based on the least square method fitting measurement variable according to the application, and the transition area knife mark on the stress cone surface is measured in real time, the joint mark area is removed, the grinding and polishing tool is guided to polish the smooth transition of the circular cone surface close to the ideal cone model S0, and the pain point problem in the background art is solved.

[0031] The above embodiments are only preferred technical solutions of the application, and should not be regarded as a limitation of the application. The protection scope of the application should be based on the technical solutions claimed in the claims, including equivalent replacement solutions of the technical features claimed in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the application.

Claims

1. A device for controlled grinding and polishing of the stress cone surface of high-voltage cables based on least squares fitting of measurement variables, characterized in that, Includes a 3D measuring camera, control system, motion mechanism, polishing tools, TOF laser measurement module, and six-dimensional force sensor module; The three-dimensional measuring camera is suspended at a distance h in the axial direction from the top of the cable stress cone and is used to measure the spatial coordinate data of the contour points of the knife marks and joint marks on the stress cone surface of the high-voltage cable. The TOF laser measurement module is integrated with the polishing tool and is used to measure the spatial distance data of the stress cone conical surface in the polishing area in real time. The six-dimensional force sensor module is connected to the grinding and polishing tool and is used to adjust the force compensation and pressure of the grinding and polishing tool. The motion mechanism is used to drive the grinding and polishing tool to move in the circumferential direction and to lift in the Z-axis direction; The control system is electrically connected to the three-dimensional measuring camera, motion mechanism, polishing tool, TOF laser measuring module and six-dimensional force sensor module, respectively, and is used to receive data, perform fitting calculations and issue control commands.

2. The device for controlled grinding and polishing of the stress cone surface of high-voltage cables based on least squares fitting of measurement variables according to claim 1, characterized in that, The motion mechanism includes a servo motor, a Z-axis module, a Y-axis module, and a pitch axis module; the servo motor is used to drive the grinding and polishing tool to move circumferentially along the ring rack fixture; the Z-axis module is used to drive the grinding and polishing tool to lift along the Z-axis direction; the Y-axis module and the pitch axis module are used to adjust the position and posture of the grinding and polishing tool so that the grinding working surface of the grinding and polishing tool is parallel to the generatrix of the ideal cone model S0.

3. The device for controlled grinding and polishing of the stress cone surface of high-voltage cables based on least squares fitting of measurement variables according to claim 1, characterized in that, The polishing tool includes a constant force polishing belt machine and a sanding belt; the sanding belt is the polishing working surface, and the constant force polishing belt machine adjusts the polishing force under the action of a six-dimensional force sensor module.

4. The device for controlled grinding and polishing of the stress cone surface of high-voltage cables based on least squares fitting of measurement variables according to claim 1, characterized in that, It also includes a clamping and locking fixture; the clamping and locking fixture is used to install the device on the stress cone of the horizontal and vertical high-voltage cable sections and clamp and lock it with the cable as the center.

5. The device for controlled grinding and polishing of the stress cone surface of high-voltage cables based on least squares fitting of measurement variables according to claim 1, characterized in that, The data obtained by the three-dimensional measuring camera is used to construct the stress cone point cloud model S1. The control system calculates the ideal cone model S0 based on the stress cone angle θ and the size L0 of the cone surface generatrix, and nests the ideal cone model S0 in the stress cone point cloud model S1 to mark the margin area.

6. A method for controlled grinding and polishing of the stress cone surface of a high-voltage cable based on least squares fitting of measured variables, applied to the apparatus for controlled grinding and polishing of the stress cone surface of a high-voltage cable based on least squares fitting of measured variables as described in any one of claims 1 to 5, characterized in that, Includes the following steps: S1: Measurement and Modeling Stage: The polishing device is installed on the stress cone of the horizontal and vertical high-voltage cable sections and clamped around the cable. A three-dimensional measuring camera suspended at a distance h along the axial direction of the top of the stress cone measures the stress cone of the high-voltage cable. The spatial coordinate data of the contour points of the knife marks and joint marks on the stress cone surface of the cable joint are measured. A relatively accurate contour curve is fitted and processed to obtain the stress cone point cloud model S1. Simultaneously, a spatial coordinate system with the conductor at the top of the stress cone as the center is constructed. Based on the cone angle θ and the size L0 of the cone generatrix, an ideal cone model S0 with the same generatrix size L0 and bottom radius r0 is calculated as the comparison model of the stress cone model S1. After all the measurement and modeling is completed, it is sent back to the control system. The control system nests the ideal cone model S0 into the stress cone model S1 and marks the overall and local margin areas of the stress cone model S1. S2: Assembly and Segmentation Stage: Before processing, adjust the position and posture of the grinding and polishing tool according to the cone angle θ of the ideal cone model S0, so that the working surface of the sanding belt is parallel to the cone generatrix of the model S0. Simultaneously, divide the model S0 into n cone-shaped surfaces along the direction of the cone generatrix with △L0 as the segment generatrix length. S3: Segmented Processing Stage: When grinding and polishing the conical surface with a segmented generatrix length of △L0, the motion mechanism first guides the grinding and polishing tool, which has been positioned and adjusted, to grind along the circumferential direction of the conical surface from the starting point near the bottom of the stress cone. Simultaneously, the spatial distance data of the tool marks and tool joint area contour points on the stress cone surface of the grinding area are measured in real time according to the TOF laser measurement module integrated with the grinding and polishing tool. The synchronous control system fits the spatial distance data based on the least squares method to fit the current grinding and polishing process. The slope of the segmented stress cone conical surface and the cross-sectional circle of the conical surface are combined to correct the model data of the stress cone model S1 corresponding to the current segment. The model data is compared with the ideal cone model S0. The removal allowance of the tool marks and tool joint marks in the overlapping transition area of ​​the conical surface of the current segment grinding and polishing process is calculated compared with the ideal model S0. The feedback control system adjusts the force compensation and pressing amount of the grinding tool according to the real-time calculated removal allowance until the removal allowance of the entire circle area of ​​the processed conical surface is ground and polished to correspond to the ideal cone model S0. S4: Segmentation and repositioning stage: After the current segment is processed, while the grinding and polishing tool moves along the circumferential direction of the conical surface, the motion mechanism drives the grinding and polishing tool to be raised by Δh height along the Z-axis. After the raising is completed, the grinding of the next segment of the conical surface area of ​​the stress cone begins. S5: Repeat steps S3-S4 until the excess material measured in the overlapping transition area and the joint marks area of ​​the entire cone surface of the high-voltage cable stress cone is removed by grinding and polishing. After the three-dimensional measuring camera measures and compares the model to the ideal cone model S0, the grinding and polishing operation is completed.

7. The method for controlled grinding and polishing of high-voltage cable stress cone surfaces based on least squares fitting of measurement variables according to claim 6, characterized in that, In step S2, the data for △L0 depends on the size of the grinding surface of the polishing tool.

8. The method for controlled grinding and polishing of high-voltage cable stress cone surfaces based on least squares fitting of measurement variables according to claim 6, characterized in that, In step S3, the specific process of fitting spatial distance data based on the least squares method is as follows: The analytical stress cone point cloud model S1 yields a sample set (x) of contour points of the tool marks and tool joint marks on the current segmented stress cone surface. i y i ), i = 1, 2, 3, ..., N; The distance from the i-th sample contour point on the cross-sectional circle of the stress cone to the center of the stress cone is denoted as d, which is obtained by fitting the curve using the least squares method. i ,but: ； The ideal cone model S0 is nested within the stress cone model S1. The i-th sample contour point (A) of the ideal cone model S0 i B i Then, the error between the radii of the fitted circles corresponding to the current two sample contour points is: ； Sample set (x) i y i The expressions for the error and Q(A,B) for i=1,2,3,...,N are: ； The spatial distance data of the i-th sample contour point measured by the TOF laser measurement module is D. i Correct the sample set error and Q(A,B) to a minimum, so that d i =D i ;Right now: 。 9. The method for controlled grinding and polishing of high-voltage cable stress cone surfaces based on least squares fitting of measurement variables according to claim 6, characterized in that, In step S4, △h is calculated based on the data of the ideal cone model S0. The ideal cone model has a consistent slope, which can unify the slope offset during the n-segment transposition process along the generatrix of the stress cone from the bottom of the cone upwards during processing, and polish the transition area of ​​each segment of the cone surface of the stress cone to a smooth transition.

10. The method for controlled grinding and polishing of high-voltage cable stress cone surfaces based on least squares fitting of measurement variables according to claim 9, characterized in that, The formula for calculating Δh based on the data of the ideal cone model S0 is as follows: ； Where △h is the lifting height, △L0 is the segment generatrix length, r0 is the base radius, and n is the number of segments.

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