An electric permanent-magnetic-electromagnetic hybrid adsorption optimization method for a large air gap workpiece

Abstract

The present application relates to magnetic adsorption technical field, specifically to a kind of electric permanent magnet-electromagnetic hybrid adsorption optimization method for large air gap workpiece, comprising the following steps: obtaining boundary magnetic flux balance distribution diagram by regulating magnetic flux sheet contact area and generating boundary magnetic flux balance distribution diagram, generating current adjustment rate instruction set according to attitude and magnetic flux deviation, generate tail section energy release list by using residual energy matching air gap, generate adsorption force stability control results corresponding to release sequence and rate.The present application, by effectively regulating the direction of magnetic flux in the boundary area, the magnetic flux in the boundary area is kept in order, the current change rate is dynamically corrected according to the attitude and magnetic flux deviation of the workpiece, the adaptability of the magnetic flux distribution and the air gap of the workpiece is improved, the residual energy is used to delay release before power-off and match with the air gap condition, and the adsorption force is uniform, the positioning accuracy is controllable and the energy utilization is sufficient in the grabbing and positioning of curved surface workpiece.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetic adsorption, in particular to an electric permanent magnet-electromagnet hybrid adsorption optimization method for large air gap workpieces. BACKGROUND

[0002] The technical field of magnetic adsorption involves using the suction force generated by the magnetic field to realize the fixation and handling of workpieces. The core issues include electromagnets, electric permanent magnets, and their combined applications. Research and design are mainly focused on the generation and control methods of magnetic fields, the stability and adaptability of adsorption forces, and cover the optimization of adsorption performance under different air gap conditions, from magnet structure design, magnetic field regulation methods to adsorption performance optimization under different air gap conditions. It is widely used in the grabbing, handling and positioning of large and complex workpieces. Among them, traditional electromagnetic adsorption refers to the use of energized coils to generate a magnetic field to achieve adsorption of workpieces. This method maintains the magnetic field strength by continuous power supply, and adjusts the adsorption force by coil turn design and current control. Electric permanent magnet adsorption relies on the magnetization and demagnetization of magnetic materials under the action of an external pulse current to provide a basic adsorption force. The technical issues addressed are the high energy consumption of traditional electromagnetic adsorption under large air gap conditions and the risk of power loss and demagnetization. The electric permanent magnet adsorption has limited adjustment capability in terms of air gap adaptability and adsorption stability. Especially when handling large and complex workpieces, the adsorption surface may partially detach or the adsorption force may be unevenly distributed, resulting in reduced workpiece positioning accuracy and increased safety hazards.

[0003] The existing technology has the following disadvantages: when continuously relying on the power supply of electromagnets to maintain the strength of the magnetic field, it will result in high energy consumption under large air gap conditions, and the magnetic flux distribution will be difficult to maintain stable under changes in the attitude of the workpiece and fluctuations in the air gap, resulting in insufficient or uneven adsorption force. Although electric permanent magnets can reduce the risk of power loss and demagnetization, they have limited adjustment capability in terms of air gap adaptability and adsorption stability. Especially when handling large and complex workpieces, the adsorption surface may partially detach or the adsorption force may be unevenly distributed, resulting in reduced workpiece positioning accuracy and increased safety hazards. SUMMARY

[0004] To solve the technical problems existing in the prior art, the present application provides an electric permanent magnet-electromagnet hybrid adsorption optimization method for large air gap workpieces, comprising the following steps:

[0005] To achieve the above-mentioned purpose, the present application adopts the following technical solution: an electric permanent magnet-electromagnet hybrid adsorption optimization method for large air gap workpieces, comprising the following steps:

[0006] S1: Obtain the real-time signal of the junction area of the electric permanent magnet and the electromagnetic coil, compare the magnetic communication signals of the electric permanent magnet and the electromagnetic coil in strength, judge whether the magnetic flux direction in the junction area conflicts, and generate a boundary magnetic flux balance distribution map;

[0007] S2: According to the boundary magnetic flux balance distribution map, collect the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface, combine the voltage and current records at both ends of the magnetic circuit to calculate the impedance, correspond the impedance value to the specified partition range, and generate an impedance interval current distribution table;

[0008] S3: Call the impedance interval current distribution table, extract the current output range corresponding to the real-time air gap distance, combine the workpiece attitude angle record, compare the magnetic flux value of the magnetic pole surface with the preset target magnetic flux value, calculate the change rate of the coil output current, and generate a current adjustment rate instruction set;

[0009] S4: Based on the current adjustment rate instruction set, obtain the residual electric energy stored by the electromagnetic coil in the period before power-off, call the magnetic flux intensity signal to judge whether the residual electric energy can be released, and generate a tail energy release preset list by comparing the releasable electric energy and the air gap distance measurement when it is determined that the residual electric energy can be released.

[0010] As a further scheme of the application, the boundary magnetic flux balance distribution map includes magnetic flux direction continuity, magnetic flux boundary stability, and magnetic flux and air gap matching, the impedance interval current distribution table includes current distribution interval, impedance level corresponding relationship, and current adjustment priority, the current adjustment rate instruction set includes current change rate range, attitude angle correction parameter, and target magnetic flux deviation compensation result, and the tail energy release preset list includes delayed release energy value, release applicable air gap range, and energy utilization priority order.

[0011] As a further scheme of the application, the specific steps of S1 are:

[0012] S101: Obtain the real-time signal of the junction area of the electric permanent magnet and the electromagnetic coil, compare the magnetic communication signals of the electric permanent magnet and the electromagnetic coil in strength at the same sampling time, judge whether the magnetic flux direction in the junction area conflicts according to the signal strength difference, and obtain a magnetic flux conflict judgment value;

[0013] S102: Call the magnetic flux conflict judgment value, adjust the contact area ratio of the peak magnetic conductive sheet layer and the trough magnetic conductive sheet layer in the junction area in the conflict state, re-identify the magnetic flux distribution direction in the junction area according to the change of the contact area ratio, and obtain a contact area adjustment result;

[0014] S103: According to the contact area adjustment result, readjust the magnetic flux distribution of the boundary region, and correspondingly map the adjusted magnetic flux distribution to the workpiece air gap range to obtain a boundary magnetic flux balance distribution map.

[0015] As a further scheme of the present application, the specific steps of S2 are:

[0016] S201: According to the boundary magnetic flux balance distribution map, collect the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface, call the interval data of the sampling point position as the air gap input parameter under the real-time state, combine the magnetic flux flux record at the corresponding time point to obtain an air gap section parameter set;

[0017] S202: Based on the air gap section parameter set, call the voltage and current records at the corresponding sampling time at both ends of the magnetic circuit, use the ratio of the voltage value to the current value to calculate the section impedance characteristic value, and generate a magnetic circuit section impedance characteristic value group;

[0018] S203: According to the magnetic circuit section impedance characteristic value group, correspond the magnetic circuit section impedance characteristic value to the given partition range, and use the interval where the impedance value is located and the upper limit impedance difference value in the same partition as the judgment basis to extract the real-time partition matching position, and obtain a partition impedance mapping result;

[0019] S204: Call the partition impedance mapping result, call the corresponding set current adjustment information at the matching partition position, one-by-one pair and combine the adjusted current value and the impedance mapping relationship to obtain an impedance interval current distribution table.

[0020] As a further scheme of the present application, the magnetic circuit section impedance characteristic value is a value quantifying the action relationship between voltage and current of a local section of the magnetic circuit within a target time period.

[0021] As a further scheme of the present application, the specific steps of S3 are:

[0022] S301: Call the impedance interval current distribution table, extract the current output range corresponding to the real-time air gap distance, and correspond the current output range and the real-time air gap value point by point to generate an air gap current matching group;

[0023] S302: Based on the air gap current matching group, call the workpiece attitude angle record, compare the magnetic flux value of the magnetic pole surface and the preset target magnetic flux value at the same sampling time, calculate the magnetic flux difference value, and map the magnetic flux difference value to the current output range to obtain a magnetic flux difference current interval;

[0024] S303: According to the magnetic flux difference current interval, identify the change amount and time interval of the coil output current at the continuous sampling time, calculate the change rate of the coil output current, and generate a current adjustment rate instruction set.

[0025] As a further scheme of the present application, the change rate of the coil output current represents the degree of current change in a unit time.

[0026] As a further scheme of the present application, the specific steps of S4 are:

[0027] S401: Based on the current regulation rate instruction set, the residual electric energy stored by the electromagnetic coil in the period before power-off is obtained, and the residual electric energy is determined to meet the delayed release condition by calling the magnetic flux signal, and when the delayed release condition is met, the residual electric energy is corresponded to the magnetic flux signal to obtain a delayed release energy value;

[0028] S402: According to the delayed release energy value, the energy distribution relationship of the corresponding section is identified by comparing the releasable electric energy and the real-time air gap distance measurement value, the distribution amount of the releasable energy in the section is recorded, and a tail section energy release preset list is generated.

[0029] As a further scheme of the present application, the method further comprises a S5 step:

[0030] S5: Through the tail section energy release preset list, the releasable electric energy is called, combined with the magnetic circuit impedance measurement value, the release order and the release rate are identified, the release behavior is corresponded to the workpiece positioning value, and an adsorption force stability control result is generated.

[0031] The adsorption force stability control result includes adsorption force balance, positioning information, and energy release consistency.

[0032] As a further scheme of the present application, the specific steps of S5 are:

[0033] S501: Through the tail section energy release preset list, the releasable electric energy in the section is called, combined with the magnetic circuit impedance measurement value at the corresponding time point, the section energy value and the impedance value are judged in groups, the release order is identified according to the unit reaction rate of the release electric energy to the impedance, and an energy release order number is obtained.

[0034] S502: Based on the energy release order number, the electric energy release rate is extracted in sequence, the current decay value of the section is rearranged according to the release rate, and the release rate and the unit time current change value are integrated to obtain rate contrast decay information.

[0035] S503: According to the rate contrast decay information, the section release behavior is corresponded to the workpiece positioning value one by one, the stable change degree of unit adsorption force is calculated according to the positioning coordinate point, and an adsorption force stability control result is generated.

[0036] Compared with the prior art, the present application has the following advantages and positive effects:

[0037] In the application, the magnetic flux is kept in order in the boundary by effective regulation of the conflict of the magnetic flux direction, the fine management of the current distribution is realized by combining the air gap measurement and impedance partition, the current change rate is dynamically corrected according to the workpiece posture and magnetic flux deviation, the adaptability of the magnetic flux distribution and the workpiece air gap is improved, the remaining energy is used for delayed release before power-off and matched with the air gap condition, the suction force is kept balanced and stable in the adsorption process, and the adsorption force is uniform, the positioning accuracy is controllable, and the energy is fully utilized in the grabbing and positioning of the curved workpiece. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0039] Figure 1 It is a step flowchart of the application.

[0040] Figure 2 It is a S1 refinement schematic diagram of the application.

[0041] Figure 3 It is a S2 refinement schematic diagram of the application.

[0042] Figure 4 It is a S3 refinement schematic diagram of the application.

[0043] Figure 5 It is a S4 refinement schematic diagram of the application.

[0044] Figure 6 It is a S5 refinement schematic diagram of the application. DETAILED DESCRIPTION

[0045] The technical solutions in the application will be described below with reference to the drawings.

[0046] In the embodiments of the application, the words such as "example", "for example" are used to represent as an example, illustration or description. Any embodiment or design scheme described as "example" in the application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. In fact, the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the application, the meaning expressed by "and / or" can be both, or can be one of the two.

[0047] In the embodiments of the present application, the terms "image" and "picture" can be used interchangeably, and it should be pointed out that the meanings expressed are consistent when the distinction is not emphasized.

[0048] In the embodiments of the present application, sometimes the subscript such as W1 can be written in the form of non-subscript such as W1, and the meanings expressed are consistent when the distinction is not emphasized.

[0049] In order to make the technical problems, technical solutions and advantages to be solved by the present application more clear, the following will be described in detail with reference to the drawings and specific embodiments.

[0050] Please refer to Figure 1 The embodiments of the present application provide an electric permanent magnet-electromagnet hybrid adsorption optimization method for a large air gap workpiece, comprising the following steps:

[0051] S1: Obtain the real-time signal of the junction area of the electric permanent magnet and the electromagnetic coil, compare the magnetic flux signals of the electric permanent magnet and the electromagnetic coil in strength, judge whether the magnetic flux direction in the junction area conflicts, adjust the contact area ratio of the peak flux guide sheet layer and the trough flux guide sheet layer in the junction area in the conflict state, make the magnetic flux sequentially guide in the boundary, correspond the adjusted magnetic flux distribution to the air gap range of the workpiece, and generate a boundary magnetic flux balance distribution map;

[0052] S2: According to the boundary magnetic flux balance distribution map, collect the real-time air gap value between the workpiece adsorption surface and the magnetic pole surface, combine the voltage and current records at both ends of the magnetic circuit to calculate the impedance, correspond the impedance value to the specified partition range, call the set current adjustment information in the partition range, and generate an impedance interval current distribution table;

[0053] S3: Call the impedance interval current distribution table, extract the current output range corresponding to the real-time air gap distance, combine the workpiece attitude angle record, compare the magnetic flux value of the magnetic pole surface with the preset target magnetic flux value, calculate the change rate of the coil output current, and generate a current adjustment rate instruction set;

[0054] S4: Based on the current adjustment rate instruction set, obtain the residual electric energy stored by the electromagnetic coil in the period before power-off, call the magnetic flux intensity signal to judge whether the residual electric energy can be released in delay, and when it is determined that the residual electric energy can be released in delay, compare the releasable electric energy with the air gap distance measurement value, and generate a tail energy release preset list;

[0055] S5: calling releasable electric energy through tail section energy release preset list, combining magnetic circuit impedance measurement value, identifying release order and release rate, corresponding release behavior and workpiece positioning value, generating adsorption force stability control result;

[0056] The boundary magnetic flux balance distribution includes magnetic flux direction continuity, magnetic flux boundary stability, and magnetic flux and air gap matching. The impedance interval current distribution table includes current distribution interval, impedance level corresponding relationship, and current regulation priority. The current regulation rate instruction set includes current change rate range, attitude angle correction parameter, and target magnetic flux deviation compensation result. The tail section energy release preset list includes delayed release energy value, release applicable air gap range, and energy utilization priority order. The adsorption force stability control result includes adsorption force balance, positioning information, and energy release consistency.

[0057] Please refer to Figure 2 The specific steps of S1 are as follows:

[0058] S101: obtaining real-time signals of the intersection area of the electric permanent magnet and the electromagnetic coil, comparing the strength values of the electric permanent magnet magnetic signal and the electromagnetic coil magnetic signal at the same sampling time, combining the signal strength difference to judge whether the magnetic flux direction in the intersection area conflicts, and obtaining a magnetic flux conflict judgment value;

[0059] In implementation, the Hall sensor matrix arranged in the intersection area can be used to collect signals of the two magnetic fields in real time. The magnetic field strength values of the electric permanent magnet and the electromagnetic coil are recorded automatically with extremely short sampling intervals. The frequency of obtaining data is set to 100 times per second to ensure the time consistency of the signals. The collected data is stored in the local storage and called by the central controller for processing. At a certain moment, if the magnetic induction strength value of the electric permanent magnet is 1.2 Tesla and the magnetic induction strength value of the electromagnetic coil is 1.0 Tesla, the two values are compared by difference, and a judgment is made in combination with the pre-set allowed range. If the difference is greater than the allowed range, it is immediately marked as a conflict state. In combination with the magnetic flux direction, it is found that the magnetic flux direction of the electric permanent magnet points outward, while the magnetic flux direction of the electromagnetic coil points inward. Therefore, the directions of the two are completely opposite. At this time, it is confirmed that there is a magnetic flux conflict in the intersection area. The conflict judgment value is recorded as 1. If the directions of the two are consistent and the strength difference is lower than the allowed 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 machining period to ensure the integrity of data collection and comparison, and the magnetic flux conflict judgment value is obtained.

[0060] S102: calling the magnetic flux conflict judgment value, adjusting the contact area proportion of the peak flux guide sheet layer and the trough flux guide sheet layer in the intersection area in the conflict state, re-identifying the magnetic flux distribution direction in the intersection area according to the change of the contact area proportion, and obtaining a contact area adjustment result;

[0061] In the case of conflict, the contact area ratio of the peak and trough magnetic sheet layers in the boundary area needs to be dynamically adjusted. The initial contact ratio of the peak and trough sheet layers in the boundary area is confirmed by design drawings, and the initial setting is set to 60% for the peak and 40% for the trough. The adjustment program is triggered by the control program according to the conflict judgment value. If it is determined that there is a conflict, the current difference value is read and mapped to the adjustment ratio coefficient. The contact area of the peak sheet layer is automatically calculated to be reduced, and the contact area of the trough sheet layer is automatically calculated to be increased. When the conflict difference is large, the peak contact ratio is adjusted to 57%, and the trough ratio is increased to 43%. The adjusted ratio is updated to the control model in real time, and the magnetic flux distribution direction of the boundary area is identified again. This process relies on the redistributed magnetic field strength data. It is set to detect that the magnetic flux direction of the peak area is close to vertical before adjustment, and the deviation is about 10 degrees after adjustment. The magnetic flux direction of the trough area tends to be stable, and the contact area adjustment result is obtained.

[0062] S103: According to the contact area adjustment result, the magnetic flux distribution of the boundary area is re-adjusted, and the adjusted magnetic flux distribution is correspondingly mapped to the air gap range of the workpiece to obtain a boundary magnetic flux balance distribution diagram.

[0063] The magnetic flux distribution in the boundary area needs to be re-adjusted, and the updated magnetic flux information is correspondingly mapped to the air gap range of the workpiece. In specific implementation, a geometric model of the boundary area and the air gap of the workpiece is established by using a three-dimensional modeling software. The updated peak and trough contact ratio parameters are input into the model. The software automatically divides the multiple unit areas in the boundary area according to the input parameters, and calculates the magnetic field distribution of each area. After completing the data calculation at the unit level, a magnetic flux distribution table is generated, which labels the magnetic field strength and direction of each area. The geometric range corresponding to the air gap of the workpiece is mapped point by point. The mapping result is displayed. The magnetic induction intensity in the left area of the air gap is 0.95 Tesla, and the magnetic induction intensity in the right area is 1.12 Tesla. The difference between the two is within the allowed balance range. After the mapping process is completed in the background, the distribution of the magnetic flux in the air gap is displayed in the form of vector arrows and color gradients, so that subsequent personnel can intuitively understand the magnetic flux distribution direction and strength distribution of the boundary area through the diagram, and a boundary magnetic flux balance distribution diagram is formed.

[0064] Please refer to Figure 3 , and the specific steps of S2 are as follows:

[0065] S201: According to 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 distance data of the sampling point position is used as the air gap input parameter in the real-time state, and the corresponding time point magnetic flux record is combined to obtain an air gap section parameter set.

[0066] The system needs to collect real-time air gap values ​​between the workpiece's adsorption surface and the magnetic pole surface. During execution, multiple high-precision displacement sensors are arranged between the workpiece's adsorption surface and the magnetic pole surface to acquire air gap data at a sampling frequency of 0.02 seconds. During 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 used as a geometric input condition. In the detection of a certain workpiece, sensor 1 measures an air gap of 1.8 mm, sensor 2 measures 2.0 mm, and the distance between them is 10 mm. This data 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 sensors. 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 section parameter set.

[0067] S202: Based on the air gap section parameter set, the voltage and current records at both ends of the magnetic circuit at the corresponding sampling time are called, and the section impedance characteristic value is calculated by using the ratio of voltage value to current value, and a magnetic circuit section impedance characteristic value group is generated.

[0068] The characteristic value of the section impedance is given by the formula:

[0069] ;

[0070] in, Representing the The characteristic value of the section impedance of the magnetic circuit section. Representing the The section is in Voltage values ​​at each sampling time. Representing the The section is in The current value at each sampling time. Representing the The time interval between each sampling moment and the previous sampling moment. Representing the The section is in The equivalent magnetoresistance value at each sampling time. Represents the total number of sampling times;

[0071] Formula calculation logic: By sampling the voltage of the magnetic circuit segment at different time points. With current Data, combined with material magnetoresistance values First, calculate the difference between the instantaneous electrical energy input and dissipation at each sampling point, and then multiply it by the sampling time interval. The difference is accumulated to form a total energy response value; the square root of the voltage square sum is taken as a normalization reference, and the accumulated value is divided by the reference to obtain the comprehensive impedance behavior under unit voltage response, and the absolute value operation is used to eliminate the direction influence and ensure that the impedance characteristic value is positive, reflecting the actual response strength, and the section impedance characteristic value The section impedance characteristic value represents the composite energy transmission characteristics of the entire magnetic circuit section in the sampling period, has functions such as time average, normalization and interference balance, and can effectively measure the stability and energy consistency of the magnetic circuit section, providing a quantitative basis for subsequent structure identification and abnormal diagnosis.

[0072] The section impedance characteristic value is a value used to quantify the complex interaction between voltage and current in a local section of the magnetic circuit in a specific time period, representing the overall level of the section's energy transmission and dissipation capacity. The larger the value, the more significant the energy transmission obstruction in the section, indicating structural or material abnormalities.

[0073] Parameter acquisition and value setting explanation:

[0074] The following is an explanation of the parameter acquisition method and actual value:

[0075] Voltage value : sampled and recorded every 100 ms by a high-precision voltage sensor, example sampling values: 7.2V, 7.4V, 7.3V;

[0076] Current value : measured by a Hall effect sensor at the same time node, example values: 2.5A, 2.6A, 2.7A;

[0077] Sampling time interval : the sampling period is fixed at 100 ms, i.e. 0.001 s;

[0078] Equivalent magnetic resistance : calculated based on the material structure and magnetic flux density of each section, using the formula:

[0079] ;

[0080] Where, is the length of the magnetic circuit, is the cross-sectional area; (magnetic permeability of silicon steel material);

[0081] Then:

[0082] ;

[0083] To ensure the accuracy of the calculation example, the following experimental data is listed and substituted into the formula for actual calculation,

[0084] Table 1: Measured sampling parameter table

[0085]

[0086] As shown in Table 1, the measured voltage, current and the calculated equivalent magnetic resistance value of the first section magnetic circuit at three consecutive sampling points are listed;

[0087] Parameter substitution and formula calculation:

[0088] Molecule calculation:

[0089]

[0090] Denominator calculation:

[0091] ;

[0092] Substitute the formula for calculation:

[0093] ;

[0094] The results show that under the unit voltage response, the impedance characteristic value of the section magnetic circuit is 196.33 (unit same voltage / unit magnetic motive force response), which represents the response relationship between the magnetic voltage and the equivalent magnetic resistance dissipation. In practical applications, if the preset impedance reference interval Compared with the results, it falls within the normal range, indicating that the magnetic circuit section is in an acceptable working state range;

[0095] The advantage of the formula is that by introducing the weighted difference value of voltage and magnetic resistance multiplied by time interval and normalized processing to extract the composite response characteristics, the problem of poor sensitivity to time change of traditional simple ratio method is avoided. At the same time, the local dynamic impedance response is extracted by summing the sampling sequence, which improves the anti-interference ability and discrimination accuracy in multi-section magnetic circuit state analysis.

[0096] S203: According to the magnetic circuit section impedance characteristic value group, the magnetic circuit section impedance characteristic value is corresponded to the determined partition range, and the difference value between the impedance value and the upper limit impedance in the same partition is used as the judgment basis to extract the real-time partition matching position, and the partition impedance mapping result is obtained;

[0097] The magnetic circuit section impedance value is corresponded to the pre-divided partition range, the partition range is determined by the engineers according to the equipment characteristics in the modeling stage, 0-6 ohms are defined as a low impedance area, 6-9 ohms are defined as a medium impedance area, and 9-12 ohms are defined as a high impedance area, each impedance value is located in a partition one by one, if the impedance of a certain section is 7.8 ohms, it is determined to be in the medium impedance area, and the difference value is compared with the upper limit value 9 ohms, the difference value is 1.2 ohms, which is recorded as the judgment basis, the judgment and difference value calculation of the section are continued, the real-time partition matching position is obtained, the first section is in the medium impedance area, the difference value is 0.8 ohms, the second section is in the medium impedance area, the difference value is 1.2 ohms, the third section is in the low impedance area, and the difference value is 0.5 ohms, and the partition impedance mapping result is obtained.

[0098] S204: Call the partition impedance mapping result, call the corresponding current adjustment information in the matching partition position, pair and combine the adjustment current value and the impedance mapping relationship one by one, and obtain the impedance interval current distribution table;

[0099] The corresponding current adjustment information is called in the matched partition position, in the specific execution, the current adjustment database is provided in the control module, the preset current adjustment scheme of different partition impedance intervals is recorded, the current adjustment amplitude is set to plus or minus 0.5 ampere for the medium impedance area, and the current adjustment amplitude is set to plus or minus 1.0 ampere for the high impedance area, the corresponding adjustment value is extracted from the database according to the size of the impedance difference value of each section, and is paired with the impedance mapping position one by one, the first section impedance 7.8 ohms difference value 1.2 ohms, the corresponding adjustment current value is +0.4 ampere, the second section difference value 0.8 ohms, the corresponding adjustment current value is +0.3 ampere, the pairing results of the sections are combined, and the section number, impedance value, partition position, difference value and corresponding adjustment current value are listed one by one, which are used as control instructions and are sent to the execution unit, and are used as the basis for real-time adjustment of current in subsequent operation, and the impedance interval current distribution table is obtained.

[0100] Please refer to Figure 4 , the specific steps of S3 are:

[0101] S301: Call the impedance interval current distribution table, extract the current output range corresponding to the real-time air gap distance, and correspond the current output range to the real-time air gap value point by point to generate an air gap current matching group.

[0102] The current output range corresponding to the real-time air gap distance is extracted. In the specific implementation process, the latest round of air gap detection data is read first. The air gap lengths of 1.7 mm, 1.9 mm and 2.1 mm are detected in a sampling period. According to the air gap value, the corresponding current output range is matched in the impedance interval current distribution table. The current range corresponding to the air gap of 1.7 mm is set to 2.5-2.9 A, the current range corresponding to the air gap of 1.9 mm is set to 2.7-3.0 A, and the current range corresponding to the air gap of 2.1 mm is set to 2.8-3.2 A. The results are point by point to establish a mapping relationship and are combined in order to be stored in the database in the form of a table. Each record contains the measurement point number, the real-time air gap length, the lower limit and the upper limit of the current output range, so as to be called and used subsequently. The first section record in the table is set to the current output range 2.5-2.9 A corresponding to the air gap of 1.7 mm, and the second section record is set to the current output range 2.7-3.0 A corresponding to the air gap of 1.9 mm. The corresponding relationship of the complete coverage of the real-time sampling point is guaranteed to enable the subsequent adjustment logic to be called at any time to generate the air gap current matching group.

[0103] S302: Based on the air gap current matching group, the workpiece attitude angle record is called, 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 value is calculated, and the magnetic flux difference value is mapped to the current output range to obtain the magnetic flux difference current interval;

[0104] The attitude angle record of the workpiece 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 attitude angle of the workpiece is obtained by the angle sensor installed on the support in real time. The workpiece inclination angle is set to 5 degrees in a certain sampling period. The magnetic flux value on the magnetic pole surface at this time is compared with the target magnetic flux value. The detected magnetic flux value is set to 1.05 T, and the target magnetic flux value is set to 1.10 T. The difference between the two is 0.05 T. The difference is directly mapped to the corresponding current output range in the air gap current matching group. The output range corresponding to the air gap of 1.9 mm is set to 2.7-3.0 A. According to the difference size, the adjustment interval to which the difference needs to be deviated is selected. If the detected magnetic flux value is 1.00 T at another sampling point, the target value is still 1.10 T, and the difference is 0.10 T, the difference is corresponded to a higher current output range, which is set to 2.9-3.1 A. This process is performed on the sampling points one by one and is archived as an input condition for subsequent dynamic current adjustment to obtain the magnetic flux difference current interval.

[0105] S303: According to the magnetic flux difference current interval, the change amount and the time interval of the coil output current are identified at the continuous sampling time, the change rate of the coil output current is calculated, and the current adjustment rate instruction set is generated;

[0106] The change rate of the coil output current is calculated by the formula:

[0107] ;

[0108] in, Representing the The rate of change of the output current of the coil group Representing the Group of coils in the first Current change in consecutive samplings. Representing the Group of coils in the first The time interval in a series of consecutive samples Representing the The weighting adjustment coefficient for the change in coil current in each sampling. Representing the The adjustment factor for the ratio of the corresponding current change to the square root of the time interval in each sampling. Represents the number of consecutive samples;

[0109] The formula's calculation logic is as follows: by weighted summation of the changes in the coil output current across multiple consecutive sampling points (Z times in total), it reflects the overall trend of change. Indicates the first The increment of the sampled current, combined with the weighting factor (Based on the degree of current fluctuation) its reliability is adjusted, and at the same time, through 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 above-mentioned adjusted current increments and taking the absolute value, the overall rate of change of the output current of coil a at the current moment is obtained. This not only preserves the intensity of change, but also integrates dynamic stability and time sensitivity, providing a stable and reliable quantitative basis for subsequent current adjustment commands.

[0110] The rate of change of the coil output current indicates how fast the current increases or decreases per unit time, reflecting the current's responsiveness to changes in external load or control signals. An excessively high rate of change leads to instability and requires timely adjustment to maintain a stable output.

[0111] Parameter meanings and calculation process:

[0112] : This represents the change in current of the circuit coil in group a during the k-th consecutive sampling, in amperes (A). It can be obtained by subtracting the values ​​of two consecutive samples from the same node using a current sensor. If the current in the k-th sampling is 10.5A and the current in the (k-1)-th sampling is 9.9A, then ;

[0113] : represents the time interval of the a-th group of coil in the k-th continuous sampling, unit is second (s), which can be obtained by the sampling frequency, for example, if the sampling frequency is 10 kHz, then ;

[0114] : is the weight adjustment coefficient of the current change amount, which represents the reliability degree of the change amount in the k-th sampling, which is usually determined by the current fluctuation standard deviation and the maximum fluctuation range , and the quantization method is:

[0115] ;

[0116] Example: if , , then ;

[0117] : is the time weighting adjustment factor, which reflects the sensitivity of current change and time interval, and the quantization formula is as follows:

[0118]

[0119] wherein, is the reference current (reference value), which is set to 5A, then if , , then:

[0120]

[0121] Z: represents the total number of continuous sampling, which is set according to the data smoothing requirement, generally Z=5~20, if Z=5 is set, it means that the last 5 sampling is effective;

[0122] Parameter actual sampling and calculation example:

[0123] Taking a set of experimental sampling data as an example, Z=5, the sampling period is 0.1 ms, the reference current , the maximum current fluctuation , the specific sampling data is shown in table 2;

[0124] Table 2: coil current continuous sampling data table

[0125]

[0126] Table 2 lists the current change, time interval and fluctuation standard deviation in each continuous sampling; the values of corresponding and are obtained by calculation;

[0127] Put the data into the formula to calculate:

[0128]

[0129] The sum is:

[0130] ;

[0131] Take the average and take the absolute value:

[0132] ;

[0133] The results show that the rate of change of the coil output current is , and the reference current change rate is set to 5A / s. When the calculated rate of change of the coil output current is greater than the reference value, it indicates that the current coil output current fluctuation is outside the normal adjustment range, and the current adjustment mechanism needs to be started appropriately to reduce the disturbance source.

[0134] The results show that there is a rapid fluctuation trend in the current output rate, which is caused by instantaneous changes in the load or magnetic flux disturbance.

[0135] The advantage of the formula is that by introducing weight adjustment factor and time weighting adjustment factor, not only the dynamic response ability to the credibility of the sampling data is improved, but also the robustness to abnormal sampling points is enhanced; In particular, the square root weighting mechanism of the sampling time interval effectively solves the rate distortion problem under the condition of inconsistent sampling period. In actual current control, the formula can realize more accurate change trend recognition, which is beneficial to trigger the control response in advance and improve the stability and response speed of the overall current regulation.

[0136] Please refer to Figure 5 , the specific steps of S4 are:

[0137] S401: Based on the current regulation rate instruction set, obtain the remaining energy of the electromagnetic coil stored in the period before power failure, call the magnetic flux intensity signal to determine whether the remaining energy meets the delayed release condition, and when the delayed release condition is met, the remaining energy is corresponding to the magnetic flux intensity signal to obtain the delayed release energy value.

[0138] The residual energy stored by the electromagnetic coil in a period before power-off is obtained, in a specific implementation, the energy is calculated by the coil current and storage time and recorded by the control module, the average current of the coil is set to 3 amperes before power-off, the duration is 0.5 seconds, the residual energy data is automatically converted and written into the cache area, the magnetic flux signal is called, and it is judged whether the residual energy meets the delayed release condition, the condition depends on whether the magnetic flux signal is maintained in a certain stable range, it is judged that the delayed release condition is met when the magnetic flux is continuously maintained in the interval of 1.05 to 1.15 tesla, otherwise it is directly cleared, in the case of meeting the condition, the residual energy value is corresponded to the magnetic flux signal point by point, the residual energy recorded in the detection period is 12 joules, and the corresponding magnetic flux is 1.10 tesla, then the two are paired and archived to form a set of delayed release energy values, if the magnetic flux signal drops below the threshold in the subsequent period, the delayed release mode is immediately terminated, and the delayed release energy value is obtained.

[0139] S402: According to the delayed release energy value, the energy distribution relationship of the corresponding section is identified by comparing the releasable energy and the real-time air gap distance measurement value, the distribution amount of the releasable energy in the section is recorded, and the tail section energy release preset list is generated;

[0140] The specific process of comparing the releasable energy and the real-time air gap distance measurement value is to read the air gap data obtained by the displacement sensor at the same sampling time, set the air gap values to 1.8 mm, 2.0 mm and 2.3 mm respectively in the detection of a workpiece, and call the corresponding delayed release energy value at the same time, set the delayed release energy value to 12 joules, 10 joules and 8 joules respectively, compare the two one by one, identify the energy distribution relationship of each air gap section, set the release energy distribution corresponding to the air gap 1.8 mm to 12 joules, the air gap 2.0 mm to 10 joules, and the air gap 2.3 mm to 8 joules, establish a distribution record in each section, mark the distribution amount and sampling time, arrange them in order according to the section, and mark the air gap length, corresponding energy value, sampling time stamp and delayed release identifier for each section, set the first section: air gap 1.8 mm, energy 12 joules, delayed release, time stamp t1; the second section: air gap 2.0 mm, energy 10 joules, delayed release, time stamp t2; the third section: air gap 2.3 mm, energy 8 joules, delayed release, time stamp t3, as the direct basis for energy control after power-off, and the tail section energy release preset list is obtained.

[0141] Please refer to Figure 6 , the specific steps of S5 are:

[0142] S501: Through the tail section energy release preset list, call the releasable electric energy in the section, combine the magnetic circuit impedance measurement value at the corresponding time point, perform group judgment on the section energy value and impedance value, identify the release order according to the unit reaction rate of the released electric energy to the impedance, and obtain the energy release sequence number;

[0143] Call the releasable electric energy in each section, and analyze it in combination with the magnetic circuit impedance measurement value at the same sampling time. In actual execution, read the gap length and corresponding energy value marked in the list, set 1.8 mm corresponding to 12 joules, 2.0 mm corresponding to 10 joules, and 2.3 mm corresponding to 8 joules. At the same time, call the record value of the impedance detection device, set the corresponding impedance to 7.5 ohms, 8.0 ohms and 8.3 ohms respectively, pair each energy value with the impedance value, establish a section energy impedance combination table, and perform group judgment for each group of data. Focus on detecting the response rate of the impedance value under the release of unit energy. In the specific comparison process, if the impedance drop rate of section 1 under the release of 12 joules is greater than that of section 2 or section 3, then section 1 is marked as high priority. Execute this kind of judgment for all sections in turn to form a release sequence, numbered from the highest priority to the lowest. Set the result display order to section 1, section 3, section 2, and obtain the energy release sequence number.

[0144] S502: Based on the energy release sequence number, extract the electric energy release rate in turn, rearrange the current decay value of the section according to the release rate, and integrate the release rate and the current change value per unit time to obtain the rate contrast decay information;

[0145] Extract the electric energy release rate one by one, and rearrange the current decay value of each section. In specific execution, call the sequence number table, set the number display of section 1 to release first, set its corresponding energy release rate as the reference, and call the rate value of the subsequent sections in turn. Set the release rate of section 1 to 4.5 joules per second, that of section 3 to 3.8 joules per second, and that of section 2 to 3.5 joules per second. Match the rate with the current decay value of each section according to the sequence order. Set the current decay value of section 1 to 0.6 ampere, that of section 3 to 0.5 ampere, and that of section 2 to 0.4 ampere. Integrate the release rate and the current change value per unit time to list the number, release rate, current decay value and sampling time of each section. Set section 1: 4.5 joules per second, current decay 0.6 ampere; Section 3: 3.8 joules per second, current decay 0.5 ampere; Section 2: 3.5 joules per second, current decay 0.4 ampere. Ensure real-time performance and provide for subsequent adsorption force stability calculation, and obtain the rate contrast decay information.

[0146] S503: According to the rate of contrast attenuation information, the section release behavior is corresponded to the positioning value of the workpiece one by one, the stable variation degree of unit adsorption force is calculated according to the positioning coordinate point, and the adsorption force stability control result is generated;

[0147] The section release behavior is corresponded to the positioning value of the workpiece one by one, specifically, the positioning coordinate point of the workpiece is acquired in real time by the three-dimensional displacement sensor installed on the operation table, three key coordinate points of X=10mm, Y=20mm and Z=5mm of a certain workpiece are set, the section release behavior is paired with the coordinates, the release behavior of section 1 corresponds to the upper left corner coordinate of the workpiece, section 3 corresponds to the lower right corner coordinate of the workpiece, and section 2 corresponds to the middle coordinate of the workpiece, after the corresponding is completed, the stable variation degree of unit adsorption force is calculated according to the current attenuation of each coordinate point, the current attenuation of section 1 is 0.6 ampere at the position of X=10mm, and the release rate is converted into the variation degree of unit adsorption force 0.12 newton; the current attenuation of section 3 is 0.5 ampere at the position of X=15mm, and the corresponding variation degree is 0.10 newton, the current attenuation of section 2 is 0.4 ampere at the position of X=20mm, and the corresponding variation degree is 0.08 newton, the variation degrees of the coordinate points are summarized, the section number, coordinate position, current attenuation value and corresponding adsorption force variation degree are recorded, the execution unit is directly called, the adsorption state of the whole workpiece is kept balanced in the power-off stage, and the adsorption force stability control result is formed.

[0148] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An electric permanent-magnetic-electromagnetic hybrid adsorption optimization method for a workpiece with a large air gap, characterized in that, The method comprises the following steps: S1: obtaining real-time signals of the intersection region of the electric permanent magnet and the electromagnetic coil, comparing the magnetic flux signals of the electric permanent magnet and the electromagnetic coil in strength, judging whether the magnetic flux direction in the intersection region conflicts, and generating a boundary magnetic flux balance distribution map; S2: according to the boundary magnetic flux balance distribution map, collecting real-time air gap values between the workpiece adsorption surface and the magnetic pole surface, combining the voltage and current records at both ends of the magnetic circuit to calculate the impedance, corresponding the impedance value to a certain partition range, and generating 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 attitude angle record, comparing the magnetic flux value of the magnetic pole surface with the preset target magnetic flux value, calculating the change rate of the coil output current, and generating a current adjustment rate instruction set; S4: based on the current adjustment rate instruction set, obtaining the remaining electric energy stored by the electromagnetic coil in the period before power-off, calling the magnetic flux strength signal to judge whether the remaining electric energy can be released slowly, and when it is determined that the remaining electric energy can be released slowly, comparing the releasable electric energy with the air gap distance measurement value to generate a tail energy release preset list.

2. The method of claim 1, wherein the method is characterized by, The boundary magnetic flux balance distribution map includes magnetic flux direction continuity, magnetic flux boundary stability, and magnetic flux and air gap matching. The impedance interval current distribution table includes current distribution interval, impedance level corresponding relationship, and current adjustment priority. The current adjustment rate instruction set includes current change rate range, attitude angle correction parameter, and target magnetic flux deviation compensation result. The tail energy release preset list includes delayed release energy value, release applicable air gap range, and energy utilization priority order.

3. The method of claim 1, wherein the method is characterized by, The specific steps of S1 are: S101: obtaining real-time signals of the intersection region of the electric permanent magnet and the electromagnetic coil, comparing the strength values of the magnetic flux signals of the electric permanent magnet and the electromagnetic coil at the same sampling time, combining the signal strength difference to judge whether the magnetic flux direction in the intersection region conflicts, and obtaining a magnetic flux conflict judgment value; S102: calling the magnetic flux conflict judgment value, adjusting the contact area ratio of the peak flux guide sheet layer and the trough flux guide sheet layer in the intersection region in the conflict state, re-identifying the magnetic flux distribution direction in the intersection region according to the change of the contact area ratio, and obtaining a contact area adjustment result; S103: according to the contact area adjustment result, re-adjusting the magnetic flux distribution of the intersection region, corresponding the adjusted magnetic flux distribution to the workpiece air gap range, and obtaining a boundary magnetic flux balance distribution map.

4. The method according to claim 3, wherein, The specific steps of S2 are: S201: according to the boundary magnetic flux balance distribution map, collecting real-time air gap values between the workpiece adsorption surface and the magnetic pole surface, calling the distance data of the sampling point position as the air gap input parameter in the real-time state, combining the magnetic flux flux record at the corresponding time point, and obtaining an air gap section parameter set; S202: based on the air gap section parameter set, calling the voltage and current records at both ends of the magnetic circuit at the corresponding sampling time, calculating the section impedance characteristic value by using the ratio of the voltage value to the current value, and generating a magnetic circuit section impedance characteristic value group; S203: According to the magnetic circuit section impedance characteristic value group, the magnetic circuit section impedance characteristic value is corresponded to the determined partition range, the interval of the impedance value and the upper limit impedance difference value in the same partition are used as the judgment basis, the real-time partition matching position is extracted, and the partition impedance mapping result is obtained; S204: The partition impedance mapping result is called, the corresponding set current adjustment information is called at the matching partition position, the adjustment current value and the impedance mapping relationship are one-to-one paired and combined, and the impedance interval current distribution table is obtained.

5. The method of claim 3, wherein the method is characterized by, The magnetic circuit section impedance characteristic value is a numerical value quantifying the action relationship between voltage and current of the local section of the magnetic circuit in the target time period.

6. The method of claim 4, wherein the method is characterized by, The specific steps of S3 are: S301: The impedance interval current distribution table is called, the current output range corresponding to the real-time air gap distance is extracted, the current output range is point-by-point corresponded to the real-time air gap value, and the air gap current matching group is generated; S302: Based on the air gap current matching group, the workpiece attitude angle record is called, the magnetic flux value on the same sampling time is compared with the preset target magnetic flux value, the magnetic flux difference value is calculated, and the magnetic flux difference current interval is obtained by mapping the magnetic flux difference value to the current output range; S303: According to the magnetic flux difference current interval, the change amount and time interval of the coil output current are identified at the continuous sampling time, the change rate of the coil output current is calculated, and the current adjustment rate instruction set is generated.

7. The method of claim 6, wherein the method is characterized by, The change rate of the coil output current represents the change degree of the current per unit time.

8. The method of claim 6, wherein the method is characterized by, The specific steps of S4 are: S401: Based on the current adjustment rate instruction set, the residual energy stored by the electromagnetic coil in the period before power-off is obtained, and the residual energy is determined by calling the magnetic flux intensity signal whether it meets the delayed release condition. When the delayed release condition is met, the residual energy is corresponded to the magnetic flux intensity signal to obtain the delayed release energy value; S402: According to the delayed release energy value, the releasable energy and the real-time air gap distance measurement value are compared, the energy distribution relationship of the corresponding section is identified, the distribution amount of the releasable energy in the section is recorded, and the tail section energy release preset list is generated.

9. The method of claim 1, wherein, The method further includes the S5 step: S5: Through the tail section energy release preset list, the releasable energy is called, the magnetic circuit impedance measurement value is combined, the release order and release rate are identified, the release behavior is corresponded to the workpiece positioning value, and the adsorption force stability control result is generated; The adsorption force stability control result includes adsorption force balance, positioning information, and energy release consistency.

10. The method of claim 1, wherein, The specific steps of S5 are: S501: Through the tail section energy release preset list, the releasable energy in the section is called, the magnetic circuit impedance measurement value at the corresponding time point is combined, the section energy value and the impedance value are judged in groups, the release order is identified according to the unit reaction rate of the release energy to the impedance, and the energy release order number is obtained; S502: Based on the energy release order number, the energy release rate is extracted in sequence, the current decay value of the section is rearranged according to the release rate, and the release rate and the unit time current change value are integrated to obtain the rate contrast decay information; S503: According to the rate control attenuation information, the segment release behavior is corresponded to the workpiece positioning value one by one, the stable change degree of the unit adsorption force is calculated according to the positioning coordinate point, and the adsorption force stability control result is generated.

Images