Electro-hydraulic servo control system of high-speed numerical control turret punch press

Abstract

The invention belongs to the field of electro-hydraulic servo control, relates to a data analysis technology, and particularly relates to an electro-hydraulic servo control system of a high-speed numerical control turret punch press, which is used for solving the problem that proper PID (Proportion Integration Differentiation) parameters and acquisition period duration cannot be matched according to demand parameters of a processing task in the prior art. Comprising a control test module, a test analysis module, a configuration analysis module and a storage module. The control test module is used for carrying out control test on the electro-hydraulic servo control system: generating a plurality of test tasks, obtaining stamping processing demand pressure of the test tasks, randomly distributing configuration parameters for the test tasks, and executing the test tasks according to the configuration parameters after the configuration parameters are distributed; according to the method, the control test can be carried out on the electro-hydraulic servo control system, multiple test data of the test task under different configuration parameters are recorded after the configuration parameters are randomly distributed for the test task, and data support is provided for the test analysis process and the configuration analysis process.

Description

Technical Field

[0001] The invention belongs to the field of electro-hydraulic servo control and relates to data analysis technology, in particular to an electro-hydraulic servo control system of a high-speed numerical control turret punch press. Background Art

[0002] An electro-hydraulic servo system refers to a hydraulic control system with a servo element (servo valve or servo pump) as the control core. It is usually composed of a command device, a controller, an amplifier, a hydraulic source, a servo element, an actuator, a feedback sensor and a load.

[0003] The invention patent with announcement number CN108873702B discloses a linear anti-disturbance control method and device for an electro-hydraulic position servo control system. The linear anti-disturbance control method provides a control method with high precision, good stability and strong anti-disturbance capability, solves the problem of difficult PID parameter tuning, and overcomes the influence of nonlinearity and uncertainty on the performance of the control system; however, the linear anti-disturbance control method cannot match the appropriate PID parameters and the acquisition cycle length according to the required parameters of the processing task, resulting in the inability to guarantee the processing accuracy and operation stability of the electro-hydraulic servo control system.

[0004] In view of the above technical problems, this application proposes a solution. Summary of the invention

[0005] The purpose of the present invention is to provide an electro-hydraulic servo control system for a high-speed CNC turret punch press, which is used to solve the problem that the prior art cannot match appropriate PID parameters and acquisition cycle duration according to the required parameters of the processing task; The technical problem to be solved by the present invention is: how to provide an electro-hydraulic servo control system for a high-speed CNC turret punch press that can match appropriate PID parameters and acquisition cycle length according to the required parameters of the processing task.

[0006] The purpose of the present invention can be achieved through the following technical solutions: The electro-hydraulic servo control system of the high-speed CNC turret punch press includes a control test module, a test analysis module, a configuration analysis module and a storage module; The control test module is used to perform control test on the electro-hydraulic servo control system: generate several test tasks, obtain the required pressure of the stamping process of the test task, and randomly allocate configuration parameters for the test task. The configuration parameters include the duration of the sampling cycle, the proportional link parameters, the integral link parameters and the differential link parameters of the PID controller. After the configuration parameters are allocated, the test task is executed according to the configuration parameters, and the test data of the test task is recorded; the test data of all test tasks are sent to the test analysis module; The test analysis module is used to analyze the test data of the electro-hydraulic servo control system: perform numerical calculation on the test data to obtain the accuracy coefficient JD of the test task, and mark the test task as a normal execution task or an abnormal execution task according to the accuracy coefficient JD; the maximum value and the minimum value of the demand pressure of the test task constitute a demand range, divide the demand range into several demand intervals, obtain the sampling priority range of the demand interval, and send the sampling priority ranges of all demand intervals to the configuration analysis module; The configuration analysis module is used to perform configuration analysis on the PID parameters of the electro-hydraulic servo control system: all the normally executed tasks in the demand interval are sorted in ascending order according to the precision coefficient JD to obtain a precision sequence, the abnormally executed tasks in the demand interval are marked as abnormal objects i, i=1, 2, ..., n, n is a positive integer, and the normally executed tasks are compared and analyzed with the abnormal object i: the ratio data BL of the configuration PID parameters of the normally executed tasks and the abnormal object i is obtained i , integral data JF i And the differential data WF i And perform numerical calculation to obtain the priority coefficient YX for normal execution of the task; mark the control priority parameters of the demand interval according to the priority coefficient YX; the control priority parameters and the sampling priority range constitute the parameter control set of the demand interval, and send the parameter control sets of all demand intervals to the storage module for storage.

[0007] Furthermore, the test data includes force control data LK, position control data WK and speed control data SK. The force control data LK is the absolute value of the difference between the stamping control pressure when the test task is executed and the expected control pressure. The position control data WK is the absolute value of the difference between the stamping control displacement when the test task is executed and the expected control displacement. The speed control data SK is the absolute value of the difference between the stamping control speed when the test task is executed and the expected control speed.

[0008] Furthermore, the specific process of marking a test task as a normal execution task or an abnormal execution task includes: obtaining the accuracy threshold JDmax through the storage module, and comparing the accuracy coefficient JD of the test task with the accuracy threshold JDmax: if the accuracy coefficient JD is less than the accuracy threshold JDmax, it is determined that the control accuracy of the test task meets the requirements, and the corresponding test task is marked as a normal execution task; if the accuracy coefficient JD is greater than or equal to the accuracy threshold JDmax, the corresponding test task is marked as an abnormal execution task.

[0009] Furthermore, the process of obtaining the sampling priority range of the demand interval includes: forming a sampling set by the duration of the sampling period of all normally executed tasks whose demand pressure is within the demand interval, performing variance calculation on all elements in the sampling set to obtain the concentration coefficient of the sampling set, and comparing the concentration coefficient with a preset concentration threshold: if the concentration coefficient is less than the concentration threshold, then summing and averaging all elements in the sampling set to obtain the standard value of the duration of the demand interval; if the concentration coefficient is greater than or equal to the concentration threshold, then eliminating the maximum element and the minimum element in the sampling set, and then recalculating the concentration coefficient of the sampling set, and so on, until the concentration coefficient is less than the concentration threshold; the standard low value SCd and the standard high value SCg of the duration are obtained by the formulas SCd=t1×SC and SCg=t2×CS, t1 and t2 are both proportional coefficients, and 0.85≤t1≤0.95, 1.05≤t2≤1.15, and the standard low value SCd and the standard high value SCg of the duration form the sampling priority range of the demand interval.

[0010] Furthermore, the ratio data BL i is the proportional coefficient K in the proportional link of normal execution of tasks p The proportional coefficient K in the proportional link with the abnormal object i pi Absolute value of the difference; integral data JF i is the integral time constant T in the integral link of normal execution of tasks I The integral time constant T in the integral link of the abnormal execution task Ii Absolute value of the difference; differential data WF i is the differential time constant T in the differential link of normal execution task D The differential time constant T in the differential link of the abnormal execution task Di The absolute value of the difference.

[0011] Furthermore, the specific process of marking the control priority parameters of the demand interval includes: after all the normal execution tasks in the demand interval are compared and analyzed with the abnormal object i, the normal execution task with the largest priority coefficient YX in the demand interval is marked as the priority configuration task, and the proportional coefficient K p , the integral time constant T in the integral link I And the differential time constant T in the differential link D Control priority parameters that constitute the demand interval.

[0012] The present invention has the following beneficial effects: 1. The control test module can be used to perform control tests on the electro-hydraulic servo control system. After randomly allocating configuration parameters for the test task, multiple test data of the test task under different configuration parameters are recorded to provide data support for the test analysis process and configuration analysis process; 2. The test analysis module can be used to analyze the test data of the electro-hydraulic servo control system, differentiate the test tasks according to the accuracy coefficient, and then generate the sampling priority range by combining the differentiated marking results with the required parameters. The sampling priority range can optimize the duration of the sampling cycle of the test task; 3. The configuration analysis module can be used to perform configuration analysis on the PID parameters of the electro-hydraulic servo control system. The priority configuration tasks in the normal execution tasks can be screened by combining the accuracy coefficient and the priority coefficient. Then, the PID parameters of the priority configuration tasks are selected to optimize the configuration of the required range, thereby improving the control accuracy and operation stability of the electro-hydraulic servo control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 paying creative work.

[0014] Figure 1 is a system block diagram of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of a PID control system according to a first embodiment of the present invention; Figure 3 This is a flow chart of the method of Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0015] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] Embodiment 1: Figure 1 As shown, the electro-hydraulic servo control system of the high-speed CNC turret punch press includes a control test module, a test analysis module, a configuration analysis module and a storage module. The control test module, the test analysis module, the configuration analysis module and the storage module are communicatively connected in sequence, and the storage module is also communicatively connected to the test analysis module.

[0017] The control test module is used to perform control tests on the electro-hydraulic servo control system: generate several test tasks, obtain the required pressure of the stamping processing of the test tasks, and randomly allocate configuration parameters for the test tasks. The configuration parameters include the duration of the sampling cycle, the proportional link parameters, the integral link parameters and the differential link parameters of the PID controller. After the configuration parameters are allocated, the test tasks are executed according to the configuration parameters, and the test data of the test tasks are recorded. The test data include force control data LK, position control data WK and speed control data SK. The force control data LK is the absolute value of the difference between the stamping control pressure and the expected control pressure when the test task is executed, the position control data WK is the absolute value of the difference between the stamping control displacement and the expected control displacement when the test task is executed, and the speed control data SK is the absolute value of the difference between the stamping control speed and the expected control speed when the test task is executed; send the test data of all test tasks to the test analysis module; after randomly allocating configuration parameters for the test tasks, record multiple test data of the test tasks under different configuration parameters to provide data support for the test analysis process and the configuration analysis process.

[0018] like Figure 2 As shown, the PID controller is a linear controller that forms a control deviation e(t) based on the given value r(t) and the actual output value y(t). The relationship is: a) Proportional link: It can quickly and proportionally reflect the deviation signal e(t) of the control system. Once a deviation occurs, the controller will immediately control it to reduce the deviation. The implementation formula of the proportional part can be expressed as: K P e(t), proportionality coefficient K P The role of K is to speed up the response of the system. P The larger the K, the faster the system responds. P As the system increases, overshoot and oscillation will occur. P The value cannot be too large; otherwise, K P If it is too small, it will increase the adjustment time, reduce the response speed, and affect the dynamic and static characteristics of the system.

[0019] b) Integral link: used to eliminate static error and improve the system's error-free degree; time constant T I Determines the strength of the integral effect, T I When it is larger, the integral effect is weak, and it takes longer to eliminate the deviation, but the system is not prone to oscillation; T I When it is smaller, the integral effect is stronger and the time required to eliminate the deviation is shorter, but the system is prone to oscillation.

[0020] Differential link: reflects the changing trend of the deviation signal, improves the system's action speed, and reduces the adjustment time; the strength of the differential effect is determined by the differential time constant T D Decision; T DThe larger the value is, the stronger the effect of suppressing deviation change is. D The smaller it is, the weaker the effect of suppressing deviation changes is, which has a greater impact on the stability of the system.

[0021] The test analysis module is used to analyze the test data of the electro-hydraulic servo control system: the accuracy coefficient JD of the test task is obtained by the formula JD=k1×LW+k2×WK+k3×SK, where k1, k2 and k3 are all proportional coefficients, and k1>k2>k3>1; the accuracy threshold JDmax is obtained through the storage module, and the accuracy coefficient JD of the test task is compared with the accuracy threshold JDmax: if the accuracy coefficient JD is less than the accuracy threshold JDmax, it is determined that the control accuracy of the test task meets the requirements, and the corresponding test task is marked as a normal execution task; if the accuracy coefficient JD is greater than or equal to the accuracy threshold JDmax, the corresponding test task is marked as an abnormal execution task; the maximum value and the minimum value of the demand pressure of the test task constitute the demand range, and the demand range is divided into several demand intervals. The duration of the sampling period of all normal execution tasks whose demand pressure is within the demand interval constitutes a sampling set, and the variance of all elements in the sampling set is calculated to obtain the concentration coefficient of the sampling set, and the concentration coefficient is compared with the preset concentration threshold: if the concentration coefficient is less than the concentration threshold, all elements in the sampling set are summed and averaged. The average value is used to obtain the standard value of the duration of the demand interval; if the concentration coefficient is greater than or equal to the concentration threshold, the maximum element and the minimum element in the sampling set are eliminated, and then the concentration coefficient of the sampling set is recalculated, and so on, until the concentration coefficient is less than the concentration threshold; the standard low value SCd and the standard high value SCg of the duration are obtained through the formula SCd=t1×SC and SCg=t2×CS, t1 and t2 are both proportional coefficients, and 0.85≤t1≤0.95, 1.05≤t2≤1.15, the standard low value SCd and the standard high value SCg of the duration constitute the demand interval The sampling priority range of all demand intervals is sent to the configuration analysis module; the test tasks are differentiated and marked according to the precision coefficient, and then the sampling priority range is generated by combining the differentiated marking results with the demand parameters. The sampling priority range can optimize the duration of the sampling cycle of the test task; the shorter the sampling cycle, the more accurate the digital simulation, and the closer the control effect is to continuous control. For most algorithms, shortening the sampling cycle can improve the performance of the control loop, but if the sampling cycle is too short, the frequency sampling will inevitably take up more computer working time and increase the calculation burden.

[0022] The configuration analysis module is used to perform configuration analysis on the PID parameters of the electro-hydraulic servo control system: sort all the normal execution tasks in the demand interval according to the accuracy coefficient JD from small to large to obtain the accuracy sequence, mark the abnormal execution tasks in the demand interval as abnormal object i, i=1, 2, ..., n, n is a positive integer, compare and analyze the normal execution tasks with the abnormal object i: obtain the ratio data BL of the configuration PID parameters of the normal execution tasks and the abnormal object i i , integral data JF i And the differential data WF i , ratio data BL i is the proportional coefficient K in the proportional link of normal execution of tasks p The proportional coefficient K in the proportional link with the abnormal object i pi Absolute value of the difference; integral data JF i is the integral time constant T in the integral link of normal execution of tasks I The integral time constant T in the integral link of the abnormal execution task Ii Absolute value of the difference; differential data WF i is the differential time constant T in the differential link of normal execution task D The differential time constant T in the differential link of the abnormal execution task Di The absolute value of the difference; by the formula The priority coefficient YX of the normal execution task is obtained, where m1, m2, m3, m4 and m5 are all proportional coefficients, and m1>m2>m3>m4>m5>1, and XH is the serial number of the normal execution object in the precision sequence; after all the normal execution tasks in the demand interval are compared and analyzed with the abnormal object i, the normal execution task with the largest priority coefficient YX in the demand interval is marked as the priority configuration task, and the proportional coefficient K of the priority configuration task in the proportional link is used. p , the integral time constant T in the integral link I And the differential time constant T in the differential link D The control priority parameters of the demand interval are formed; the parameter control set of the demand interval is formed by the control priority parameters and the sampling priority range, and the parameter control sets of all demand intervals are sent to the storage module for storage; the priority configuration tasks in the normally executed tasks are screened in combination with the accuracy coefficient and the priority coefficient, and then the PID parameters of the priority configuration tasks are selected to optimize the configuration of the demand interval, so as to improve the control accuracy and operation stability of the electro-hydraulic servo control system.

[0023] Embodiment 2: Figure 3 As shown, the electro-hydraulic servo control method of the high-speed CNC turret punch press comprises the following steps: Step 1: Perform control test on the electro-hydraulic servo control system: generate several test tasks, randomly assign configuration parameters to the test tasks, execute the test tasks according to the configuration parameters after the configuration parameters are assigned, and record the test data of the test tasks; Step 2: Perform numerical calculation on the test data of the test task to obtain the precision coefficient JD. According to the precision coefficient JD, the test task is marked as a normal execution task or an abnormal execution task. The maximum and minimum demand pressure values ​​of the test task constitute a demand range. The demand range is divided into several demand intervals, and the sampling priority range of the demand interval is marked. Step 3: Analyze the configuration of the PID parameters of the electro-hydraulic servo control system, compare and analyze the normal execution task with the abnormal object i, and obtain the priority coefficient YX of the normal execution task. Mark the control priority parameters of the demand interval by the priority coefficient YX.

[0024] The electro-hydraulic servo control system of the high-speed CNC turret punch press generates several test tasks when working, randomly allocates configuration parameters for the test tasks, executes the test tasks according to the configuration parameters after the configuration parameters are allocated, and records the test data of the test tasks; numerically calculates the test data of the test tasks to obtain the accuracy coefficient JD, and marks the test tasks as normal execution tasks or abnormal execution tasks according to the accuracy coefficient JD. The demand range is composed of the maximum demand pressure and the minimum demand pressure of the test tasks, and the demand range is divided into several demand intervals, and the sampling priority range of the demand interval is marked; the PID parameters of the electro-hydraulic servo control system are configured and analyzed, and the normal execution task is compared and analyzed with the abnormal object i to obtain the priority coefficient YX of the normal execution task, and the control priority parameters of the demand interval are marked by the priority coefficient YX.

[0025] The above contents are merely examples and explanations of the structure of the present invention. The technicians in this technical field may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the structure of the invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

[0026] The above formulas are obtained by collecting a large amount of data for software simulation and selecting a formula close to the true value. The coefficients in the formula are set by technicians in this field according to actual conditions; such as: formula JD=k1×LW+k2×WK+k3×SK; technicians in this field collect multiple groups of sample data and set corresponding accuracy coefficients for each group of sample data; substitute the set accuracy coefficients and the collected sample data into the formula, any three formulas constitute a three-variable linear equation group, screen the calculated coefficients and take the average, and obtain the values ​​of k1, k2 and k3 as 4.52, 2.83 and 2.01 respectively; The size of the coefficient is to quantify each parameter to obtain a specific value for subsequent comparison. The size of the coefficient depends on the amount of sample data and the preliminary setting of the corresponding precision coefficient for each set of sample data by technical personnel in this field; as long as it does not affect the proportional relationship between the parameter and the quantized value, such as the precision coefficient is proportional to the value of the force control data.

[0027] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0028] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. The electro-hydraulic servo control system of high-speed CNC turret punch press is characterized by: It includes a control test module, a test analysis module, a configuration analysis module and a storage module; The control test module is used to perform control test on the electro-hydraulic servo control system: generate several test tasks, obtain the required pressure of the stamping process of the test task, and randomly allocate configuration parameters for the test task. The configuration parameters include the duration of the sampling cycle, the proportional link parameters, the integral link parameters and the differential link parameters of the PID controller. After the configuration parameters are allocated, the test task is executed according to the configuration parameters, and the test data of the test task is recorded; the test data of all test tasks are sent to the test analysis module; The test analysis module is used to analyze the test data of the electro-hydraulic servo control system: perform numerical calculation on the test data to obtain the accuracy coefficient JD of the test task, and mark the test task as a normal execution task or an abnormal execution task according to the accuracy coefficient JD; the maximum value and the minimum value of the demand pressure of the test task constitute a demand range, divide the demand range into several demand intervals, obtain the sampling priority range of the demand interval, and send the sampling priority ranges of all demand intervals to the configuration analysis module; The configuration analysis module is used to perform configuration analysis on the PID parameters of the electro-hydraulic servo control system: all the normally executed tasks in the demand interval are sorted in ascending order according to the precision coefficient JD to obtain a precision sequence, the abnormally executed tasks in the demand interval are marked as abnormal objects i, i=1, 2, ..., n, n is a positive integer, and the normally executed tasks are compared and analyzed with the abnormal object i: the ratio data BL of the configuration PID parameters of the normally executed tasks and the abnormal object i is obtained i , integral data JF i And the differential data WF i And perform numerical calculation to obtain the priority coefficient YX for normal execution of the task; mark the control priority parameters of the demand interval according to the priority coefficient YX; the control priority parameters and the sampling priority range constitute the parameter control set of the demand interval, and send the parameter control sets of all demand intervals to the storage module for storage.

2. The electro-hydraulic servo control system of the high-speed CNC turret punch press according to claim 1, characterized in that: The test data includes force control data LK, position control data WK and speed control data SK. The force control data LK is the absolute value of the difference between the stamping control pressure when the test task is executed and the expected control pressure. The position control data WK is the absolute value of the difference between the stamping control displacement when the test task is executed and the expected control displacement. The speed control data SK is the absolute value of the difference between the stamping control speed when the test task is executed and the expected control speed.

3. The electro-hydraulic servo control system of the high-speed CNC turret punch press according to claim 2, characterized in that: The specific process of marking a test task as a normal execution task or an abnormal execution task includes: obtaining the accuracy threshold JDmax through the storage module, and comparing the accuracy coefficient JD of the test task with the accuracy threshold JDmax: if the accuracy coefficient JD is less than the accuracy threshold JDmax, it is determined that the control accuracy of the test task meets the requirements, and the corresponding test task is marked as a normal execution task; if the accuracy coefficient JD is greater than or equal to the accuracy threshold JDmax, the corresponding test task is marked as an abnormal execution task.

4. The electro-hydraulic servo control system of the high-speed CNC turret punch press according to claim 3, characterized in that: The process of obtaining the sampling priority range of the demand interval includes: forming a sampling set from the duration of the sampling period of all normally executed tasks whose demand pressure is within the demand interval, performing variance calculation on all elements in the sampling set to obtain the concentration coefficient of the sampling set, and comparing the concentration coefficient with the preset concentration threshold: if the concentration coefficient is less than the concentration threshold, then summing and averaging all elements in the sampling set to obtain the standard value of the duration of the demand interval; if the concentration coefficient is greater than or equal to the concentration threshold, then eliminating the maximum element and the minimum element in the sampling set, and then recalculating the concentration coefficient of the sampling set, and so on, until the concentration coefficient is less than the concentration threshold; the standard low value SCd and the standard high value SCg of the duration are obtained by the formula SCd=t1×SC and SCg=t2×CS, t1 and t2 are both proportional coefficients, and 0.85≤t1≤0.95, 1.05≤t2≤1.15, and the standard low value SCd and the standard high value SCg of the duration form the sampling priority range of the demand interval.

5. The electro-hydraulic servo control system of the high-speed CNC turret punch press according to claim 4, characterized in that: Ratio data BL i is the proportional coefficient K in the proportional link of normal execution of tasks p The proportional coefficient K in the proportional link with the abnormal object i pi Absolute value of the difference; integral data JF i is the integral time constant T in the integral link of normal execution of tasks I The integral time constant T in the integral link of the abnormal execution task Ii Absolute value of the difference; differential data WF i is the differential time constant T in the differential link of normal execution task D The differential time constant T in the differential link of the abnormal execution task Di The absolute value of the difference.

6. The electro-hydraulic servo control system of the high-speed CNC turret punch press according to claim 5, characterized in that: The specific process of marking the control priority parameters of the demand interval includes: after all the normal execution tasks in the demand interval are compared and analyzed with the abnormal object i, the normal execution task with the largest priority coefficient YX in the demand interval is marked as the priority configuration task, and the control priority parameters of the demand interval are composed of the proportional coefficient Kp of the priority configuration task in the proportional link, the integral time constant TI in the integral link, and the differential time constant TD in the differential link.

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