Electric permanent magnet-electromagnetic mixed adsorption optimization method for large-air-gap workpiece

Abstract

The invention relates to the technical field of magnetic adsorption, in particular to an electro-permanent magnet-electromagnetic mixed adsorption optimization method for a large-air-gap workpiece, which comprises the following steps of: acquiring a magnetic flux signal of a boundary area, regulating and controlling the contact area of a magnetic conductive sheet to generate a boundary magnetic flux balance distribution diagram, generating a current regulation rate instruction set according to an attitude and magnetic flux deviation, and calculating a magnetic flux balance distribution diagram; and a tail-section energy release list is generated by matching the residual energy with the air gap, and an adsorption force stability control result is generated corresponding to the release sequence and rate. According to the invention, through effective regulation and control of the magnetic flux direction conflict of the boundary area, the magnetic flux keeps sequential guidance in the boundary, the current change rate is dynamically corrected according to the workpiece attitude and the magnetic flux deviation, the adaptability of the magnetic flux distribution and the workpiece air gap is improved, and the residual energy is used for delayed release and is matched with the air gap condition in the period before power failure. And uniform adsorption force, controllable positioning precision and full energy utilization are realized in the process of grabbing and positioning the curved-surface workpiece.

Description

Technical Field

[0001] The present invention relates to the field of magnetic adsorption technology, in particular to an electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces. Background Art

[0002] The field of magnetic adsorption technology involves using the suction force generated by the magnetic field to fix and transport workpieces. The core issues include electromagnets, electropermanent magnets and their combined applications. Research and design mainly focus on the generation and control methods of the magnetic field, and the stability and adaptability of the adsorption force. It covers everything from magnet structure design, magnetic field control methods to the optimization of adsorption performance under different air gap conditions. It is widely used in the grasping, handling and positioning of large and complex workpieces. Among them, traditional electromagnetic adsorption refers to the adsorption of workpieces by generating a magnetic field by an energized coil. This method maintains the magnetic field strength through continuous power supply, and adjusts the adsorption force by means of coil turn design and current control. Electro-permanent magnetic adsorption relies on magnetic materials to achieve magnetization and demagnetization under the action of an external pulse current to provide basic adsorption force. The technical issues it targets are the problems that traditional electromagnetic adsorption requires a large amount of energy input under large air gap conditions and there is a risk of power failure and demagnetization, as well as the problem that electro-permanent magnetic adsorption is insufficient in adjusting its anti-air gap ability. It uses electro-permanent magnets as the basic constant adsorption source, and realizes real-time coordinated regulation of the magnetic field through dynamic compensation of the electromagnetic coil. At the same time, it relies on the air gap sensor to obtain real-time distance information between the workpiece and the adsorption surface, and uses the current regulation mechanism to complete the adaptive distribution of the magnetic field strength to construct a hybrid magnetic field model suitable for large curved workpieces.

[0003] The shortcomings of the existing technology are that when it continuously relies on electromagnet power supply to maintain the magnetic field strength, it will lead to excessive energy consumption under large air gap conditions. The magnetic flux distribution is difficult to maintain stability under the changes in the workpiece posture and the fluctuation of the air gap, resulting in insufficient or unbalanced adsorption force. Although electropermanent magnets can reduce the risk of power failure and demagnetization, they have limited adjustment capabilities in terms of air gap adaptability and adsorption stability. Especially when transporting large and complex workpieces, local detachment of the adsorption surface or uneven distribution of adsorption force is likely to occur, resulting in a decrease in workpiece positioning accuracy and increased safety hazards. Summary of the Invention

[0004] In order to solve the technical problems existing in the prior art, an embodiment of the present invention provides an electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large-gap workpieces, comprising the following steps: In order to achieve the above object, the present invention adopts the following technical solution: an electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces, comprising the following steps: S1: Acquire real-time signals from the interface between the permanent magnet and the electromagnetic coil, compare the strength of the permanent magnet magnetic flux signal with the electromagnetic coil magnetic flux signal, determine whether there is a conflict in the magnetic flux direction in the interface area, and generate a boundary magnetic flux balance distribution map; S2: Based on the boundary flux balance distribution diagram, the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface is collected, and the impedance is calculated by combining the voltage and current records at both ends of the magnetic circuit. The impedance value is mapped to the established partition range to generate an impedance interval current distribution table; S3: Calling the impedance interval current distribution table, extracting the current output range corresponding to the real-time air gap distance, combining the workpiece posture angle record, comparing the magnetic flux value on the magnetic pole surface with the preset target magnetic flux value, calculating the rate of change of the coil output current, and generating a current regulation rate instruction set; S4: Based on the current regulation rate instruction set, the residual electric energy stored in the electromagnetic coil in the period before power failure is obtained, and the magnetic flux intensity signal is called to determine whether the residual electric energy can be delayed in release. When it is determined that the release can be delayed, the releasable electric energy is compared with the air gap distance measurement value to generate a preset list of tail-end energy release.

[0005] As a further solution of the present invention, the boundary flux balance distribution diagram includes flux direction continuity, flux boundary stability, and flux and air gap matching; the impedance interval current distribution table includes current distribution interval, impedance level correspondence, and current regulation priority; the current regulation rate instruction set includes current change rate range, attitude angle correction parameters, and target flux deviation compensation results; the tail section energy release preset list includes delayed release energy value, release applicable air gap range, and energy utilization priority.

[0006] As a further solution of the present invention, the specific steps of S1 are: S101: Acquire a real-time signal from the interface between the electropermanent magnet and the electromagnetic coil, compare the strength values ​​of the electropermanent magnet magnetic flux signal and the electromagnetic coil magnetic flux signal at the same sampling time, and determine whether a magnetic flux direction conflicts within the interface based on the signal strength difference to obtain a magnetic flux conflict determination value; S102: calling the magnetic flux conflict determination value, adjusting the contact area ratio between the peak magnetic conductive layer and the valley magnetic conductive layer in the boundary area in the conflict state, and re-identifying the magnetic flux distribution direction in the boundary area according to the change in the contact area ratio to obtain a contact area adjustment result; S103: Readjust the magnetic flux distribution in the boundary area according to the contact area adjustment result, and map the adjusted magnetic flux distribution to the workpiece air gap range to obtain a boundary magnetic flux balance distribution diagram.

[0007] As a further solution of the present invention, the specific steps of S2 are: S201: Based on the boundary magnetic flux balance distribution diagram, real-time air gap values ​​between the workpiece adsorption surface and the magnetic pole surface are collected, and the spacing data of the sampling point positions are used as air gap input parameters in real time. The air gap parameters are combined with the magnetic flux records at the corresponding time points to obtain an air gap segment parameter set. S202: Based on the air gap segment parameter set, call the voltage and current records at the two ends of the magnetic circuit at the corresponding sampling time, use the ratio of the voltage value to the current value to calculate the segment impedance characteristic value, and generate a magnetic circuit segment impedance characteristic value group; S203: According to the magnetic circuit section impedance characteristic value group, the magnetic circuit section impedance characteristic value is mapped to a predetermined partition range, and within the same partition, the difference between the impedance value interval and the partition upper limit impedance is used as a judgment basis to extract the real-time partition matching position and obtain the partition impedance mapping result; S204: calling the partition impedance mapping result, calling the corresponding set current adjustment information at the matching partition position, and pairing the adjustment current value with the impedance mapping relationship one by one to obtain an impedance interval current distribution table.

[0008] As a further solution of the present invention, the magnetic circuit section impedance characteristic value is a numerical value that quantifies the interaction relationship between voltage and current in a local section of the magnetic circuit within a target time period.

[0009] As a further solution of the present invention, the specific steps of S3 are: S301: calling the impedance interval current distribution table, extracting the current output range corresponding to the real-time air gap distance, and matching the current output range with the real-time air gap value point by point to generate an air gap current matching group; S302: Based on the air gap current matching group, calling the workpiece posture angle record, comparing the magnetic flux value of the magnetic pole surface with the preset target magnetic flux value at the same sampling time, calculating the magnetic flux difference, and mapping the magnetic flux difference to the current output range to obtain the magnetic flux difference current range; S303: Identify the change amount and time interval of the coil output current at continuous sampling moments according to the magnetic flux difference current interval, calculate the change rate of the coil output current, and generate a current regulation rate instruction set.

[0010] As a further solution of the present invention, the rate of change of the coil output current represents the degree of change of the current per unit time.

[0011] As a further solution of the present invention, the specific steps of S4 are: S401: Based on the current regulation rate instruction set, the residual electric energy stored in the electromagnetic coil in the period before power failure is obtained, and the magnetic flux intensity signal is used to determine whether the residual electric energy meets the delayed release condition. When the delayed release condition is met, the residual electric energy is matched with the magnetic flux intensity signal to obtain the energy value that can be delayed released; S402: According to the deferred release energy value, the releasable electric energy is compared with the real-time air gap distance measurement value, the energy distribution relationship of the corresponding section is identified, the distribution amount of the releasable energy is recorded in the section, and a preset list of tail section energy release is generated.

[0012] As a further embodiment of the present invention, the method further comprises step S5: S5: calling the releasable electrical energy through the preset list of tail-end energy release, identifying the release sequence and release rate in combination with the magnetic circuit impedance measurement, matching the release behavior with the workpiece positioning value, and generating the adsorption force stability control result; The adsorption force stability control result includes adsorption force balance, positioning information, and energy release consistency.

[0013] As a further solution of the present invention, the specific steps of S5 are: S501: Using the preset list of tail-segment energy release, the amount of electrical energy that can be released in the segment is retrieved. Combined with the magnetic circuit impedance measurement at the corresponding time point, the segment energy value and impedance value are grouped and judged. The release sequence is identified based on the unit reaction rate of the released electrical energy to the impedance, and an energy release sequence number is obtained. S502: extracting the electric energy release rate based on the energy release sorting number, rearranging the current attenuation value of the segment according to the release rate, and integrating the release rate with the current change value per unit time to obtain rate control attenuation information; S503: According to the rate control attenuation information, the segment release behavior is matched one by one with the workpiece positioning value, and the stable change degree of the unit adsorption force is calculated according to the positioning coordinate point to generate the adsorption force stability control result.

[0014] Compared with the prior art, the advantages and positive effects of the present invention are: In the present invention, by effectively regulating the conflict of magnetic flux directions in the boundary area, the magnetic flux is kept in sequential orientation within the boundary, and the refined management of current distribution is achieved by combining air gap measurement and impedance zoning. The current change rate is dynamically corrected according to the workpiece posture and magnetic flux deviation, and the adaptability of the magnetic flux distribution to the workpiece air gap is improved. The residual energy is used to delay the release in the period before power failure and match it with the air gap conditions, so that the suction force remains balanced and stable during the adsorption process, and uniform adsorption force, controllable positioning accuracy and full energy utilization are achieved in the grasping and positioning of curved workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 Schematic diagram of the steps of the present invention; Figure 2 This is a schematic diagram of the refinement of S1 of the present invention; Figure 3 This is a schematic diagram of the refinement of S2 of the present invention; Figure 4 This is a schematic diagram of the refinement of S3 of the present invention; Figure 5 This is a schematic diagram of the refinement of S4 of the present invention; Figure 6 This is a detailed schematic diagram of S5 of the present invention. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0018] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as an "exemplary" in the present invention should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of the word "exemplary" is intended to present concepts in a concrete manner. Furthermore, in the embodiments of the present invention, "and / or" can mean both or either of the two.

[0019] In the embodiments of the present invention, the terms "image" and "picture" may sometimes be used interchangeably. It should be noted that, when the distinction is not emphasized, the meanings they convey are the same. The terms "of," "corresponding," and "corresponding" may sometimes be used interchangeably. It should be noted that, when the distinction is not emphasized, the meanings they convey are the same.

[0020] In the embodiments of the present invention, sometimes a subscript such as W1 may be written as a non-subscript such as W1. When the difference is not emphasized, the meanings to be expressed are the same.

[0021] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0022] See also Figure 1The embodiment of the present invention provides an electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces, comprising the following steps: S1: Acquire real-time signals from the interface between the electro-permanent magnet and the electromagnetic coil, compare the strength of the electro-permanent magnet magnetic flux signal with the electromagnetic coil magnetic flux signal, determine whether there is a conflict in the magnetic flux direction in the interface area, and adjust the contact area ratio between the peak magnetic conductive layer and the valley magnetic conductive layer in the interface area in the conflict state to guide the magnetic flux sequentially within the boundary. The adjusted magnetic flux distribution is matched with the workpiece air gap range to generate a boundary magnetic flux balance distribution diagram; S2: Based on the boundary flux balance distribution diagram, the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface is collected. The impedance is calculated by combining the voltage and current records at both ends of the magnetic circuit. The impedance value is mapped to the established partition range, and the current adjustment information set within the partition range is called to generate the impedance interval current distribution table; S3: Call the impedance interval current distribution table, extract the current output range corresponding to the real-time air gap distance, combine it with the workpiece posture angle record, compare the magnetic flux value on the magnetic pole surface with the preset target magnetic flux value, calculate the change rate of the coil output current, and generate the current regulation rate instruction set; S4: Based on the current regulation rate instruction set, the residual electric energy stored in the electromagnetic coil in the period before power failure is obtained, and the magnetic flux intensity signal is used to determine whether the residual electric energy can be delayed and released. If it is determined that the release can be delayed, the releasable electric energy is compared with the air gap distance measurement value to generate a preset list of tail-end energy release; S5: Through the preset list of tail-end energy release, the releasable electrical energy is called, combined with the magnetic circuit impedance measurement value, the release sequence and release rate are identified, the release behavior is matched with the workpiece positioning value, and the adsorption force stability control result is generated; The boundary flux balance distribution diagram includes flux direction continuity, flux boundary stability, and flux and air gap matching. The impedance interval current distribution table includes current distribution interval, impedance level correspondence, and current regulation priority. The current regulation rate instruction set includes current change rate range, attitude angle correction parameters, and target flux deviation compensation results. The tail-end energy release preset list includes delayed release energy value, release applicable air gap range, and energy utilization priority. The adsorption force stability control results include adsorption force balance, positioning information, and energy release consistency.

[0023] See also Figure 2 , the specific steps of S1 are: S101: Acquire a real-time signal from the interface between the electropermanent magnet and the electromagnetic coil, compare the strength values ​​of the electropermanent magnet magnetic flux signal and the electromagnetic coil magnetic flux signal at the same sampling time, and determine whether a magnetic flux direction conflicts within the interface based on the signal strength difference to obtain a magnetic flux conflict determination value; In practice, the Hall sensor matrix arranged in the boundary area can be used to collect signals of the two magnetic fields in real time, and the magnetic field strength values ​​of the electropermanent magnet and the electromagnetic coil can be automatically recorded at a very short sampling interval. The data can be acquired at a sampling frequency of 100 times per second to ensure the time consistency of the signal. The collected data will be stored in the local memory and called by the central controller for processing. At a certain moment, if the magnetic induction intensity value of the electropermanent magnet is 1.2 Tesla and the magnetic induction intensity value of the electromagnetic coil is 1.0 Tesla, the difference between the two will be compared and judged in combination with the pre-set allowable range. If the difference is greater than the allowable range, it is immediately marked as a conflict state and identified in combination with the magnetic flux direction. If it is found during the detection that the magnetic flux direction of the permanent magnet points outward, while the magnetic flux direction of the electromagnetic coil points inward, then the two directions are completely opposite. At this time, it is confirmed that there is a magnetic flux conflict in the intersection area, and the conflict judgment value is recorded as 1. If the directions of the two are consistent and the intensity difference is lower than the allowable range in another sampling period, it is determined that there is no conflict, and the conflict judgment value is recorded as 0. The whole process can be repeated hundreds of times in a workpiece processing cycle to ensure the integrity of data collection and comparison and obtain the magnetic flux conflict judgment value.

[0024] S102: calling the magnetic flux conflict determination value, adjusting the contact area ratio between the peak magnetic conductive layer and the valley magnetic conductive layer in the boundary area under the conflict state, re-identifying the magnetic flux distribution direction in the boundary area based on the change in the contact area ratio, and obtaining a contact area adjustment result; In the event of a conflict, it is necessary to dynamically adjust the contact area ratio of the peak magnetic conductive layer and the valley magnetic conductive layer in the junction area. The initial contact ratio of the peak and valley layers in the junction area is confirmed through the design drawings, and the initial setting is set to 60% for the peak and 40% for the valley. The control program triggers the adjustment program according to the conflict judgment value. If a conflict is determined to exist, the current difference size is read and mapped to the adjustment ratio coefficient. The contact area of ​​the peak layer that needs to be reduced and the contact area of ​​the valley layer that needs to be increased are automatically calculated. When the conflict difference is large, the peak contact ratio is lowered to 57% and the valley ratio is increased to 43%. The adjusted ratio will be updated to the control model in real time to re-identify the magnetic flux distribution direction of the junction area. This process depends on the redistributed magnetic field strength data. The detection setting found that the original magnetic flux direction in the peak area was close to vertical, and after adjustment, it was offset by about 10 degrees, while the magnetic flux direction in the valley area tended to be stable, and the contact area adjustment result was obtained.

[0025] S103: Re-adjusting the magnetic flux distribution in the boundary area according to the contact area adjustment result, mapping the adjusted magnetic flux distribution to the workpiece air gap range to obtain a boundary magnetic flux balance distribution map; It is necessary to readjust the magnetic flux distribution in the interface area and map the updated magnetic flux information to the air gap range of the workpiece. In the specific implementation, a geometric model of the interface area and the workpiece air gap is established through 3D modeling software, and the updated peak and valley contact ratio parameters are input into the model. The software automatically divides the interface area into multiple unit areas according to the input parameters, and calculates the magnetic field distribution of each area one by one. After completing the unit-level data calculation, a magnetic flux distribution table will be generated, marking the magnetic field strength and direction of each area, and mapping the geometric range corresponding to the workpiece air gap point by point. The mapping result shows that the magnetic induction intensity in the area on the left side of the air gap is 0.95 Tesla, while the magnetic induction intensity in the area on the right side is 1.12 Tesla. The difference between the two is within the allowable balance range. After the mapping process is completed in the background, the distribution of the magnetic flux in the air gap in the interface area is displayed in the form of vector arrows and color gradients, so that subsequent personnel can intuitively grasp the magnetic flux distribution direction and intensity distribution in the interface area through diagrams, forming a boundary magnetic flux balance distribution map.

[0026] See also Figure 3 , the specific steps of S2 are: S201: Based on the boundary magnetic flux balance distribution diagram, the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface is collected, the spacing data of the sampling point position is used as the real-time air gap input parameter, and the air gap segment parameter set is obtained by combining the magnetic flux records at the corresponding time points; It is necessary to collect the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface. During execution, multiple high-precision displacement sensors are arranged between the workpiece adsorption surface and the magnetic pole surface to obtain air gap data at a sampling frequency of 0.02 seconds. When recording, the measurement point number of each sensor is bound to the corresponding timestamp to ensure a one-to-one correspondence between space and time. At the same time, the pre-set sampling point spacing is called as the geometric input condition. In a certain workpiece detection, the air gap sampled by sensor 1 is 1.8 mm, and that of sensor 2 is 2.0 mm. The spacing between the two is 10 mm. It is input into the control module and combined with the magnetic flux recording information at that time point. The magnetic flux data comes from the synchronous measurement of the magnetic flux sensor. It is set that the magnetic flux detected at the same time is 0.015 Weber. The control program combines the air gap data, sensor spacing and magnetic flux to obtain the air gap segment parameter set.

[0027] S202: Based on the air gap section parameter set, the voltage and current records at the two ends of the magnetic circuit at the corresponding sampling time are retrieved, and the section impedance characteristic value is calculated using the ratio of the voltage value to the current value to generate a magnetic circuit section impedance characteristic value group; The characteristic value of the section impedance is calculated using the formula: ; in, Representative The characteristic value of the section impedance of the section magnetic circuit, Representative Section No. The voltage value at each sampling moment, Representative Section No. The current value at each sampling moment, Representative The time interval between a sampling moment and the previous sampling moment, Representative Section No. The equivalent magnetic resistance value at each sampling moment is: Represents the total number of sampling moments; Formula calculation logic: by sampling the voltage of the magnetic circuit section at different time points With current Data, combined with the material's magnetic resistance value , first calculate the difference between the instantaneous power input and dissipation at each sampling point, and multiply it by the sampling time interval , the difference is accumulated to form the total energy response; the square root of the voltage square sum is used as the normalization benchmark, the accumulated value is divided by the benchmark to obtain the comprehensive impedance behavior under the unit voltage response, the absolute value operation is used to eliminate the direction effect, ensure that the impedance characteristic value is positive, reflect the actual response strength, and the output section impedance characteristic value It represents the composite energy conduction characteristics of the entire magnetic circuit section within the sampling period, and has functions such as time series averaging, normalization, and interference balance. It can effectively measure the state stability and energy consistency of the magnetic circuit section, providing a quantitative basis for subsequent structural identification and abnormality diagnosis; The section impedance characteristic value is used to quantify the composite relationship between voltage and current in a certain local section of the magnetic circuit within a specific time period. It reflects the overall level of the section's ability to conduct and dissipate electromagnetic energy. The larger the value, the more significant the obstruction to energy transmission in the section, indicating the presence of structural or material anomalies. Parameter acquisition and value setting instructions: The following is a description of how to obtain the parameters and their actual values: Voltage value :The high-precision voltage sensor samples and records every 100ms. Example sampling values: 7.2V, 7.4V, 7.3V; Current value : Measured by Hall effect sensor at the same time node, example values: 2.5A, 2.6A, 2.7A; Sampling time interval : The sampling period is fixed, 100ms, or 0.001s; Equivalent magnetoresistance : Calculated based on the material structure and magnetic flux density of each section, using the formula: ; in, is the magnetic path length, is the cross-sectional area; (Magnetic permeability of silicon steel sheet material); but: ; To ensure the accuracy of the calculation example, the following experimental data are listed and substituted into the formula for actual calculation. Table 1: Measured sampling parameters

[0028] As shown in Table 1, the measured voltage, current and calculated equivalent magnetic resistance values ​​at three consecutive sampling points of the magnetic circuit in the first section are listed; Parameter substitution and formula calculation: Molecular computing:

[0029] Denominator calculation: ; Substitute into the formula for calculation: ; The results show that under unit voltage response, the impedance characteristic value of the magnetic circuit in this section is 196.33 (unit voltage / unit magnetomotive force response), which represents the response relationship between magnetic voltage and equivalent magnetoresistance dissipation. In practical applications, if the impedance is compared with the preset impedance reference interval, the impedance characteristic value of the magnetic circuit in this section is 196.33 (unit voltage / unit magnetomotive force response). By comparison, the results fall within the normal range, indicating that the magnetic circuit section is in an acceptable working condition range; The benefit of the formula is that by introducing the weighted difference between voltage and magnetic resistance multiplied by the time interval and extracting the composite response characteristics after normalization, the problem of poor sensitivity to time changes in the traditional simple ratio method is avoided; at the same time, the enhanced extraction of local dynamic impedance response is achieved by summing the sampling sequence, thereby improving the anti-interference ability and discrimination accuracy in the analysis of multi-segment magnetic circuit states.

[0030] S203: Based on the magnetic circuit section impedance characteristic value group, the magnetic circuit section impedance characteristic value is mapped to a predetermined partition range. Within the same partition, the difference between the impedance value interval and the partition upper limit impedance is used as a judgment basis to extract the real-time partition matching position and obtain the partition impedance mapping result; The impedance value of the magnetic circuit section corresponds to the pre-divided partition range. The partition range is determined by the engineering personnel according to the equipment characteristics during the modeling stage. 0 to 6 ohms is defined as the low impedance zone, 6 to 9 ohms is defined as the medium impedance zone, and 9 to 12 ohms is defined as the high impedance zone. Each impedance value is partitioned and positioned one by one. If the impedance of a section is 7.8 ohms, it is judged to be in the medium impedance zone and compared with the upper limit value of 9 ohms in the zone. The difference is 1.2 ohms. This difference is recorded as the basis for judgment, and the section judgment and difference calculation are continued to complete to obtain the real-time partition matching position. The first section is set in the medium impedance zone with a difference of 0.8 ohms, the second section is in the medium impedance zone with a difference of 1.2 ohms, and the third section is in the low impedance zone with a difference of 0.5 ohms. The partition impedance mapping result is obtained.

[0031] S204: calling the partition impedance mapping result, calling the corresponding set current adjustment information at the matching partition position, and pairing the adjustment current value with the impedance mapping relationship one by one to obtain the impedance interval current distribution table; The corresponding current regulation information is retrieved at the matched partition position. During the specific execution, a current regulation database is provided in the control module to record the preset current regulation schemes for different partition impedance intervals. The current regulation amplitude is set to plus or minus 0.5 amperes for the medium impedance zone and plus or minus 1.0 amperes for the high impedance zone. According to the difference between the impedance of each section and the upper limit, the corresponding adjustment value is extracted from the database and paired with the impedance mapping position one by one. The impedance of the first section is set to 7.8 ohms and the difference is 1.2 ohms, corresponding to the adjustment current value of +0.4 amperes, and the difference of the second section is set to 0.8 ohms, corresponding to the adjustment current value of +0.3 amperes. The pairing results of the sections are combined, and the section number, impedance value, partition position, difference and corresponding adjustment current value are listed one by one. They are sent to the execution unit as control instructions, and used as the basis for real-time current adjustment in subsequent operations to obtain the impedance interval current distribution table.

[0032] See also Figure 4 , the specific steps of S3 are: S301: Calling the impedance interval current distribution table, extracting the current output range corresponding to the real-time air gap distance, and matching the current output range with the real-time air gap value point by point to generate an air gap current matching group; To extract the current output range corresponding to the real-time air gap distance, the system first reads the latest round of air gap detection data and sets the air gap lengths detected within a sampling period to be 1.7 mm, 1.9 mm, and 2.1 mm, respectively. Based on the air gap values, the system matches the corresponding current output ranges in the impedance interval current allocation table. For example, the current range corresponding to an air gap of 1.7 mm is set to 2.5 to 2.9 amps, the current range corresponding to an air gap of 1.9 mm is set to 2.7 to 3.0 amps, and the current range corresponding to an air gap of 2.1 mm is set to 2.8 to 3.9 amps. 2 amps, the results are mapped point by point, combined in sequence, and stored in the database in a table. Each record contains the measurement point number, real-time air gap length, lower limit and upper limit of the current output range for subsequent retrieval and use. The first section in the setting table records an air gap of 1.7 mm corresponding to a current output range of 2.5 to 2.9 amps, and the second section records an air gap of 1.9 mm corresponding to a current output range of 2.7 to 3.0 amps, which completely covers the corresponding relationship of the real-time sampling points and ensures that the subsequent adjustment logic can be called at any time to generate an air gap current matching group.

[0033] S302: Based on the air gap current matching group, the workpiece posture angle record is called, and the magnetic flux value on the magnetic pole surface is compared with the preset target magnetic flux value at the same sampling time. The magnetic flux difference is calculated and mapped to the current output range to obtain the magnetic flux difference current range; The workpiece's attitude angle is recorded and compared with the preset target flux value at the same sampling moment. The workpiece's attitude angle is acquired in real time by an angle sensor mounted on a bracket. During a sampling cycle, the workpiece's tilt angle is set to 5 degrees. The pole surface flux value at that moment is compared with the target flux value. The detected flux value is set to 1.05 Tesla, while the target flux value is 1.10 Tesla, with a difference of 0.05 Tesla. This difference is directly mapped to the corresponding current output range in the air gap current matching group, set to within the output range of 2.7 to 3.0 amperes for a 1.9 mm air gap. The adjustment range to be biased is selected based on the size of the difference. At another sampling point, if the detected flux value is 1.00 Tesla and the target value is still 1.10 Tesla, with a difference of 0.10 Tesla, the difference is mapped to a higher current output range of 2.9 to 3.1 amperes. This process is performed for each sampling point and archived as input for subsequent dynamic current adjustment, resulting in the flux difference current range.

[0034] S303: Identifying the change amount and time interval of the coil output current at consecutive sampling moments based on the magnetic flux difference current interval, calculating the change rate of the coil output current, and generating a current regulation rate instruction set; The rate of change of the coil output current is calculated using the formula: ; in, Representative The rate of change of the output current of the coil group, Representative The coil is in the The current change in consecutive samples, Representative The coil is in the The time interval between consecutive samples, Representative The weight adjustment coefficient corresponding to the coil current change in the sampling time is: Representative The adjustment factor corresponding to the ratio of the current change to the square root of the time interval in the sub-sampling is Represents the number of consecutive samplings; Formula calculation logic: By taking the weighted sum of the changes in the coil output current at multiple consecutive sampling points (a total of Z times), the overall change trend is reflected. Indicates the The increment of the sub-sampled current, combined with the weight factor (Based on the current fluctuation level) adjust its credibility, and at the same time The square root of the sampling time is introduced to reflect the sensitivity to sudden and drastic changes. The core logic of the formula is: by summing and averaging the adjusted current increments and taking the absolute value, the overall rate of change of the output current of coil group a at the current moment is obtained. This not only preserves the intensity of the change, but also integrates dynamic stability and time sensitivity, providing a stable and reliable quantitative basis for subsequent current regulation instructions. The rate of change of the coil output current indicates how quickly the current increases or decreases per unit time, reflecting how quickly the current responds to changes in external loads or control signals. Too high a rate of change leads to instability and requires timely adjustment to maintain a stable output. Parameter meaning and calculation process: : represents the current change in the kth consecutive sampling of the circuit loop of group a, in amperes (A). It can be obtained by taking the difference between two consecutive sampling values ​​of the same node by the current sensor. If the kth sampling current is 10.5A and the k-1th sampling current is 9.9A, then ; : represents the time interval of the a-th group of circuit loops in the k-th continuous sampling, in seconds (s), which can be obtained by reverse calculation of the sampling frequency. For example, if the sampling frequency is 10kHz, then ; : is the weight adjustment coefficient of the current change, which indicates the reliability of the change in the kth sampling, usually calculated by the current fluctuation standard deviation With the maximum fluctuation range Jointly determined, the quantification method is: ; Example: If , ,but ; : is the time-weighted adjustment factor, which reflects the sensitivity of current changes to time intervals. The quantitative formula is as follows:

[0035] in, is the reference current (reference value), set to 5A, then if , ,but:

[0036] Z: Indicates the total number of continuous sampling times, which is set according to the data smoothing requirements. Generally, Z=5~20. If Z=5 is set, it means the most recent 5 sampling times are valid. Example of actual parameter sampling and calculation: Take a set of experimental sampling data as an example, assuming Z=5, sampling period is 0.1ms, reference current , maximum current fluctuation ,The specific sampling data are shown in Table 2; Table 2: Line loop current continuous sampling data table

[0037] Table 2 lists the current variation, time interval and standard deviation of each continuous sampling; the corresponding and The value of Substitute the data into the formula to calculate:

[0038] The sum is: ; Take the average and find the absolute value: ; The results show that the rate of change of the coil output current is , set the reference current change rate to 5A / s. When the calculated coil output current change rate is greater than the reference value, it indicates that the current circuit coil output current fluctuation exceeds the normal adjustment range, and the current regulation mechanism needs to be properly activated to reduce the disturbance source; This result shows that the current output rate has a tendency to fluctuate rapidly, which is caused by transient load changes or flux disturbances; The benefit of the formula is that by introducing Weight adjustment factor and The time-weighted adjustment factor not only improves the dynamic response capability to the credibility of the sampled data, but also enhances the robustness against abnormal sampling points. In particular, the square root weighting mechanism for the sampling time interval effectively solves the rate distortion problem when the sampling period is inconsistent. In actual current control, this formula can achieve more accurate identification of changing trends, which is conducive to triggering control responses in advance and improving the stability and response speed of the overall current regulation.

[0039] See also Figure 5 , the specific steps of S4 are: S401: Based on the current regulation rate instruction set, the residual electric energy stored in the electromagnetic coil in the period before power failure is obtained, and the magnetic flux intensity signal is used to determine whether the residual electric energy meets the delayed release condition. When the delayed release condition is met, the residual electric energy is compared with the magnetic flux intensity signal to obtain the energy value that can be delayed released; The residual energy stored in the electromagnetic coil in the cycle before power failure is obtained. In a specific implementation, this energy is calculated based on the coil current and storage time and recorded by the control module. The average current of the detection coil before power failure is set to 3 amperes and the duration is 0.5 seconds. The residual energy data is automatically converted into residual energy data and written to the cache area. The magnetic flux intensity signal is called to determine whether the residual energy meets the delayed release condition. The condition depends on whether the magnetic flux intensity signal remains within a certain stable range. When the magnetic flux intensity continuously remains in the range of 1.05 to 1.15 Tesla, the delayed release condition is determined to be met; otherwise, it is directly cleared. If the condition is met, the residual energy value is matched point by point with the magnetic flux intensity signal. If the recorded residual energy is 12 joules during the detection cycle, the corresponding magnetic flux intensity is 1.10 Tesla. The two are paired and archived to form a set of energy values ​​that can be delayed. If the magnetic flux intensity signal drops below the threshold in a subsequent cycle, the delayed release mode is immediately terminated to obtain the energy value that can be delayed.

[0040] S402: Based on the deferred release energy value, the releasable electrical energy is compared with the real-time air gap distance measurement value to identify the energy distribution relationship of the corresponding section, record the distribution amount of the releasable energy in the section, and generate a preset list of energy release in the tail section; Compare the releasable electrical energy with the real-time air gap distance measurement. The specific process is to read the air gap data collected by the displacement sensor at the same sampling moment, set it in a certain workpiece detection, and record the air gap values ​​as 1.8 mm, 2.0 mm, and 2.3 mm respectively. At the same time, call the delayed release energy value at the corresponding moment, set it to 12 joules, 10 joules, and 8 joules, compare the two one by one, identify the energy distribution relationship of each air gap segment, and set the release energy distribution corresponding to the air gap of 1.8 mm to 12 joules, the air gap of 2.0 mm to 10 joules, and the air gap of 2.3 mm to 8 joules. Ear, establish an allocation record in each section, indicate the allocation amount and sampling time, arrange them in section order, and mark the air gap length, corresponding energy value, sampling timestamp and delayed release mark for each section. Set the first section: air gap 1.8 mm, energy 12 joules, delayed release, timestamp t1; second section: air gap 2.0 mm, energy 10 joules, delayed release, timestamp t2; third section: air gap 2.3 mm, energy 8 joules, delayed release, timestamp t3, as the direct execution basis for energy control after power failure, and obtain the preset list of tail section energy release.

[0041] See also Figure 6 , the specific steps of S5 are: S501: Using the preset list of tail-segment energy release, the amount of electrical energy that can be released in the segment is retrieved. Combined with the magnetic circuit impedance measurement at the corresponding time point, the segment energy value and impedance value are grouped and judged. The release sequence is identified based on the unit reaction rate of the released electrical energy to the impedance, and the energy release sequence number is obtained. The releasable electrical energy in each section is retrieved and analyzed in combination with the magnetic circuit impedance measurement at the same sampling moment. During actual execution, the air gap length and corresponding energy value marked in the list are read, and 1.8 mm is set to 12 joules, 2.0 mm to 10 joules, and 2.3 mm to 8 joules. At the same time, the recorded values ​​of the impedance detection device are retrieved, and the corresponding impedances are set to 7.5 ohms, 8.0 ohms, and 8.3 ohms, respectively. Each energy value is paired with an impedance value to establish a section energy-impedance combination table. Group judgment is performed on each set of data, focusing on detecting the response rate of the impedance value under unit energy release. In the specific comparison process, if the impedance drop rate of section 1 under the 12 joule release condition is greater than that of section 2 or section 3, section 1 is preferentially marked as high priority. This type of judgment is performed on all sections in turn to form a release sequence, numbered from highest to lowest priority. The result display order is set to section 1, section 3, and section 2 to obtain the energy release sorting number.

[0042] S502: extracting the electric energy release rate based on the energy release sorting number, rearranging the current decay value of the segment according to the release rate, and integrating the release rate with the current change value per unit time to obtain rate-controlled decay information; Extract the electric energy release rate one by one and rearrange the current attenuation value of each section. In the specific implementation, call the sorting number table, set the number to show that section 1 is released first, set its corresponding energy release rate as the benchmark, and call the rate values ​​of subsequent sections one by one. Set the release rate of section 1 to 4.5 joules per second, section 3 to 3.8 joules per second, and section 2 to 3.5 joules per second. Match the rate with the current attenuation value of each section in the sorting order, and set the current attenuation value of section 1 to 0.6 amperes. , section 3 is 0.5 amperes, section 2 is 0.4 amperes, the release rate is integrated with the current change value per unit time, and the number, release rate, current decay value and sampling time of each section are listed. Section 1 is set to 4.5 joules per second, current decay of 0.6 amperes; section 3: 3.8 joules per second, current decay of 0.5 amperes; section 2: 3.5 joules per second, current decay of 0.4 amperes to ensure real-time performance and provide it for subsequent adsorption force stability calculations to obtain rate control decay information.

[0043] S503: According to the rate control attenuation information, the segment release behavior is matched with the workpiece positioning value one by one, and the stability change degree of the unit adsorption force is calculated according to the positioning coordinate point to generate the adsorption force stability control result; The release behavior of each section is matched with the positioning value of the workpiece one by one. During the specific execution, the positioning coordinate point of the workpiece is obtained in real time by the three-dimensional displacement sensor installed on the operating table. The three key coordinate points for detecting a certain workpiece are set to be X=10 mm, Y=20 mm, and Z=5 mm. The release behavior of the section is paired with the coordinates. The release behavior of section 1 is set to correspond to the coordinate of the upper left corner of the workpiece, section 3 to the coordinate of the lower right corner of the workpiece, and section 2 to the coordinate of the middle of the workpiece. After the correspondence is completed, the stable change degree of the unit adsorption force is calculated according to the current attenuation of each coordinate point. Set section 1 to The current decays to 0.6 amps at the X=10 mm position, which is converted into a unit adsorption force change of 0.12 Newtons based on the release rate. The current decays to 0.5 amps at the X=15 mm position in segment 3, corresponding to a change of 0.10 Newtons. The current decays to 0.4 amps at the X=20 mm position in segment 2, corresponding to a change of 0.08 Newtons. The changes in the coordinate points are summarized, and the segment number, coordinate position, current decay value, and corresponding adsorption force change are recorded for direct call by the execution unit to ensure that the adsorption state of the entire workpiece remains balanced during the power-off stage, thereby forming an adsorption force stability control result.

[0044] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. An electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces, characterized in that: The following steps are involved: S1: Acquire real-time signals from the interface between the permanent magnet and the electromagnetic coil, compare the strength of the permanent magnet magnetic flux signal with the electromagnetic coil magnetic flux signal, determine whether there is a conflict in the magnetic flux direction in the interface area, and generate a boundary magnetic flux balance distribution map; S2: Based on the boundary flux balance distribution diagram, the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface is collected, and the impedance is calculated by combining the voltage and current records at both ends of the magnetic circuit. The impedance value is mapped to the established partition range to generate an impedance interval current distribution table; S3: Calling the impedance interval current distribution table, extracting the current output range corresponding to the real-time air gap distance, combining the workpiece posture angle record, comparing the magnetic flux value on the magnetic pole surface with the preset target magnetic flux value, calculating the rate of change of the coil output current, and generating a current regulation rate instruction set; S4: Based on the current regulation rate instruction set, the residual electric energy stored in the electromagnetic coil in the period before power failure is obtained, and the magnetic flux intensity signal is called to determine whether the residual electric energy can be delayed in release. When it is determined that the release can be delayed, the releasable electric energy is compared with the air gap distance measurement value to generate a preset list of tail-end energy release.

2. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 1 is characterized in that: The boundary flux balance distribution diagram includes flux direction continuity, flux boundary stability, and flux and air gap matching; the impedance interval current distribution table includes current distribution interval, impedance level correspondence, and current regulation priority; the current regulation rate instruction set includes current change rate range, attitude angle correction parameters, and target flux deviation compensation results; the tail section energy release preset list includes delayed release energy value, release applicable air gap range, and energy utilization priority.

3. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 1 is characterized in that: The specific steps of S1 are: S101: Acquire a real-time signal from the interface between the electropermanent magnet and the electromagnetic coil, compare the strength values ​​of the electropermanent magnet magnetic flux signal and the electromagnetic coil magnetic flux signal at the same sampling time, and determine whether a magnetic flux direction conflicts within the interface based on the signal strength difference to obtain a magnetic flux conflict determination value; S102: calling the magnetic flux conflict determination value, adjusting the contact area ratio between the peak magnetic conductive layer and the valley magnetic conductive layer in the boundary area in the conflict state, and re-identifying the magnetic flux distribution direction in the boundary area according to the change in the contact area ratio to obtain a contact area adjustment result; S103: Readjust the magnetic flux distribution in the boundary area according to the contact area adjustment result, and map the adjusted magnetic flux distribution to the workpiece air gap range to obtain a boundary magnetic flux balance distribution diagram.

4. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 3 is characterized in that: The specific steps of S2 are: S201: Based on the boundary magnetic flux balance distribution diagram, real-time air gap values ​​between the workpiece adsorption surface and the magnetic pole surface are collected, and the spacing data of the sampling point positions are used as air gap input parameters in real time. The air gap parameters are combined with the magnetic flux records at the corresponding time points to obtain an air gap segment parameter set. S202: Based on the air gap segment parameter set, call the voltage and current records at the two ends of the magnetic circuit at the corresponding sampling time, use the ratio of the voltage value to the current value to calculate the segment impedance characteristic value, and generate a magnetic circuit segment impedance characteristic value group; S203: According to the magnetic circuit section impedance characteristic value group, the magnetic circuit section impedance characteristic value is mapped to a predetermined partition range, and within the same partition, the difference between the impedance value interval and the partition upper limit impedance is used as a judgment basis to extract the real-time partition matching position and obtain the partition impedance mapping result; S204: calling the partition impedance mapping result, calling the corresponding set current adjustment information at the matching partition position, and pairing the adjustment current value with the impedance mapping relationship one by one to obtain an impedance interval current distribution table.

5. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 3, characterized in that: The magnetic circuit section impedance characteristic value is a numerical value that quantifies the interaction relationship between voltage and current in a local section of the magnetic circuit within a target time period.

6. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 4, characterized in that: The specific steps of S3 are: S301: calling the impedance interval current distribution table, extracting the current output range corresponding to the real-time air gap distance, and matching the current output range with the real-time air gap value point by point to generate an air gap current matching group; S302: Based on the air gap current matching group, calling the workpiece posture angle record, comparing the magnetic flux value of the magnetic pole surface with the preset target magnetic flux value at the same sampling time, calculating the magnetic flux difference, and mapping the magnetic flux difference to the current output range to obtain the magnetic flux difference current range; S303: Identify the change amount and time interval of the coil output current at continuous sampling moments according to the magnetic flux difference current interval, calculate the change rate of the coil output current, and generate a current regulation rate instruction set.

7. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 6, characterized in that: The rate of change of the coil output current represents the degree of change of the current per unit time.

8. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 6, characterized in that: The specific steps of S4 are: S401: Based on the current regulation rate instruction set, the residual electric energy stored in the electromagnetic coil in the period before power failure is obtained, and the magnetic flux intensity signal is used to determine whether the residual electric energy meets the delayed release condition. When the delayed release condition is met, the residual electric energy is matched with the magnetic flux intensity signal to obtain the energy value that can be delayed released; S402: According to the deferred release energy value, the releasable electric energy is compared with the real-time air gap distance measurement value, the energy distribution relationship of the corresponding section is identified, the distribution amount of the releasable energy is recorded in the section, and a preset list of tail section energy release is generated.

9. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 1, characterized in that: The method further comprises step S5: S5: calling the releasable electrical energy through the preset list of tail-end energy release, identifying the release sequence and release rate in combination with the magnetic circuit impedance measurement, matching the release behavior with the workpiece positioning value, and generating the adsorption force stability control result; The adsorption force stability control result includes adsorption force balance, positioning information, and energy release consistency.

10. The electro-permanent magnetic-electromagnetic hybrid adsorption optimization method for large air gap workpieces according to claim 1, characterized in that: The specific steps of S5 are: S501: Using the preset list of tail-segment energy release, the amount of electrical energy that can be released in the segment is retrieved. Combined with the magnetic circuit impedance measurement at the corresponding time point, the segment energy value and impedance value are grouped and judged. The release sequence is identified based on the unit reaction rate of the released electrical energy to the impedance, and an energy release sequence number is obtained. S502: extracting the electric energy release rate based on the energy release sorting number, rearranging the current attenuation value of the segment according to the release rate, and integrating the release rate with the current change value per unit time to obtain rate control attenuation information; S503: According to the rate control attenuation information, the segment release behavior is matched one by one with the workpiece positioning value, and the stable change degree of the unit adsorption force is calculated according to the positioning coordinate point to generate the adsorption force stability control result.

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