Servo motor with working condition self-adaptive capability and control method thereof

Abstract

The invention provides a servo motor with working condition adaptive capability and a control method thereof, the working condition change of the servo motor is identified according to the change of the working condition parameter of the servo motor, and when the working condition of the servo motor is changed, the working condition change scene of the servo motor is identified, and the working condition of the servo motor is changed. And adopting a working condition correction model matched with the working condition change scene to correct working condition parameters of the servo motor, the working condition correction model comprises a control feedback period T1 used for executing control feedback, a stable control period T2 used for executing stable control, a first empirical function f1 used for initializing control parameters after working condition change, and a second empirical function f2 used for calculating working condition parameter correction corresponding to the control parameters output by the first empirical function f1; and the maximum error Pmax of the second empirical function f2 is calculated, so that the servo motor has relatively high dynamic response capability and stability.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent control, and particularly relates to a servo motor with working condition self - adaptation ability and a control method thereof. Background Art

[0002] A servo motor is a motor that drives mechanical components in a servo system, and is a controllable mechanical electromagnetic device for electro - mechanical energy conversion and signal conversion in precision motion control. The rotor shaft of the servo motor can accurately reproduce the position, speed, and torque commands required by the host computer in a controlled state to drive the load object. In an automatic control system, the servo motor is used as an actuator and has characteristics such as a small electro - mechanical time constant, a strong overload capacity, and a high linearity. With the increasing level of industrial automation, servo motors are more and more widely used in industrial fields. In the industrial application field, the PID control algorithm is the most commonly used control algorithm for servo motors. It has mature technology, a simple structure, is easy to implement and maintain, and has excellent stability and reliability, and has always been the first choice for servo control systems in traditional industrial application scenarios. However, the PID control algorithm has poor adaptability to non - linear systems and insufficient dynamic response ability, and can only be used in an environment with relatively stable working conditions. Its implementation effect is difficult to meet expectations in complex working condition environments. Although traditional adaptive control algorithms can adapt to non - linear systems and have a stronger dynamic response ability compared with the PID control algorithm, their parameter convergence speed is slow, and they have a high stability risk, making it difficult to replace the PID control algorithm to implement automatic control in complex working conditions. Summary of the Invention

[0003] Based on the above problems, the present invention proposes a servo motor with working condition self - adaptation ability and a control method thereof, which have high dynamic response ability and stability.

[0004] In view of this, a first aspect of the present invention proposes a servo motor with working condition self - adaptation ability, including a control unit, and the control unit is configured to: Monitor the working condition parameters of the servo motor, where the working condition parameters are parameters reflecting the working state of the servo motor on the servo motor or the driving object of the servo motor; Identify the working condition change of the servo motor according to the change of the working condition parameters; When the working condition of the servo motor changes, identify the working condition change scenario of the servo motor; Adopt a working condition correction model matching the working condition change scenario to correct the working condition parameters of the servo motor, and the working condition correction model includes a control feedback period for performing control feedback and a stable control period for performing stable control , the first empirical function for initializing control parameters after a change in operating conditions , for calculating the first empirical function the second empirical function for calculating the correction amount of the operating condition parameters corresponding to the output control parameters , and the maximum error of the second empirical function .

[0005] The second aspect of the present invention proposes a control method for a servo motor with operating condition self - adaptation ability, including: Monitoring the operating condition parameters of the servo motor, where the operating condition parameters are parameters reflecting the working state of the servo motor on the servo motor or the driven object of the servo motor; Identifying the change in the operating condition of the servo motor according to the change in the operating condition parameters; When the operating condition of the servo motor changes, identifying the operating condition change scenario of the servo motor; Using an operating condition correction model matching the operating condition change scenario to correct the operating condition parameters of the servo motor, where the operating condition correction model includes a control feedback period for performing control feedback , a stable control period for performing stable control , the first empirical function for initializing control parameters after a change in operating conditions , for calculating the first empirical function the second empirical function for calculating the correction amount of the operating condition parameters corresponding to the output control parameters , and the maximum error of the second empirical function .

[0006] Further, the step of using an operating condition correction model matching the operating condition change scenario to correct the operating condition parameters of the servo motor specifically includes: Obtaining the parameter data of the servo motor before and after the change in operating conditions, where the parameter data includes control parameters and operating condition parameters; According to the parameter data of the servo motor before and after the change in operating conditions, the second control parameter of the servo motor after the change in operating conditions ; Inputting the second control parameter into the second empirical function to calculate the correction amount of the operating condition parameters corresponding to the second control parameter ; ; According to the maximum error of the second empirical function determining the second control parameter Corresponding range of operating condition parameter correction ; According to the correction range During the stable control period within, with the control feedback period as the control feedback period, correct the operating condition parameters of the servo motor to the target value .

[0007] Furthermore, the steps of obtaining the parameter data of the servo motor before and after the operating condition change specifically include: Determine the time when it is recognized that the operating condition of the servo motor changes as the starting time ; Obtain the first control parameter of the servo motor before the operating condition change and the first operating condition parameter ; Calculate the change value of the operating condition parameter of the servo motor at the starting time moment .

[0008] Furthermore, according to the correction range During the stable control period within, with the control feedback period as the control feedback period, the steps of correcting the operating condition parameters of the servo motor to the target value specifically include: At the first control feedback period after the starting time moment, input the second control parameter to the drive unit of the servo motor ; Obtain the operating condition parameters of the first control feedback period through the feedback unit of the servo motor ; Judge whether the operating condition parameters of the first control feedback period fall within the correction range ; When the operating condition parameters of the first control feedback period fall within the correction range within, fit the first operating condition parameter curve and the second operating condition parameter curve for defining the correction range of the operating condition parameters within a stable control period; With the control feedback period as the iteration period, perform iterative control on the servo motor so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve .

[0009] Further, both the first operating condition parameter curve and the second operating condition parameter curve are parabolas with the coordinate point as the vertex, and the symmetry axes of the first operating condition parameter curve and the second operating condition parameter curve are straight lines passing through the coordinate point and perpendicular to the time axis.

[0010] Further, after the step of determining whether the operating condition parameter in the first control feedback cycle falls within the correction amount range , it further includes: When the operating condition parameter in the first control feedback cycle does not fall within the correction amount range , a valid correction amount range is re - determined according to the boundary difference between the operating condition parameter and the correction amount range ; The valid operating condition change scenario corresponding to the valid correction amount range is matched in the database; The operating condition correction model of the valid operating condition change scenario is loaded to re - execute the step of correcting the operating condition parameters of the servo motor by using the operating condition correction model matched with the operating condition change scenario.

[0011] Further, the step of performing iterative control on the servo motor with the control feedback cycle as the iteration period, so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve specifically includes: Calculating the number of iteration periods within a stable control period : ; Initializing the integer calculation variable ; During the iterative control process, each time an iteration is performed, the value of is incremented by 1, so that the value of always represents the number of steps that have been iterated currently; Each time an iteration is performed, the correction amount range of the current iteration period is calculated according to the functions of the first operating condition parameter curve and the second operating condition parameter curve; The operating condition parameter of the current iteration period is obtained through the feedback unit of the servo motor; According to the operating condition parameter of the current iteration period and the correction amount range Adjust the difference of the boundary for the control parameter of the

[0012] iteration cycle. Further, the steps of identifying the operating condition change of the servo motor according to the change of the operating condition parameters specifically include: Read the pre-configured threshold value of the change of the operating condition parameters ; Obtain the control instruction sent by the control unit of the servo motor to the drive unit of the servo motor in the previous control feedback cycle, where the control instruction includes the third control parameter of the previous control feedback cycle , and the target value of the operating condition parameter corresponding to the third control parameter in the current control feedback cycle ; Obtain the operating condition parameters of the current control feedback cycle through the feedback unit of the servo motor ; Calculate the difference between the operating condition parameters of the current control feedback cycle and the target value : ; Judge whether the difference is greater than the threshold value of the change of the operating condition parameters ; When the difference is greater than the threshold value of the change of the operating condition parameters , it is determined that the operating condition of the servo motor has changed.

[0013] Further, before the step of identifying the operating condition change scenario of the servo motor, it also includes: Configure the type of the host device of the servo motor and the characteristics of the change of the operating condition parameters of the host device of the servo motor under various operating condition change scenarios in the database; The steps of identifying the operating condition change scenario of the servo motor specifically include: Extract the characteristics of the change of the operating condition parameters of the servo motor; Match the characteristics of the change of the operating condition parameters of the servo motor with the characteristics of the change of the operating condition parameters of various operating condition change scenarios under the corresponding host device type in the database; Identify the operating condition change scenario of the servo motor according to the matching result.

[0014] The present invention provides a servo motor with working condition self - adaptation ability and its control method. The working condition change of the servo motor is identified according to the change of the working condition parameters of the servo motor. When the working condition of the servo motor changes, the working condition change scenario of the servo motor is identified, and the working condition parameters of the servo motor are corrected by using a working condition correction model matching the working condition change scenario. The working condition correction model includes a control feedback period for performing control feedback , a stable control period for performing stable control , a first empirical function for initializing control parameters after the working condition change , for calculating the first empirical function A second empirical function for calculating the correction amount of the working condition parameters corresponding to the control parameters output The maximum error , so that the servo motor has high dynamic response ability and stability. Description of the Drawings

[0015] Figure 1 FIG. is a schematic diagram of a servo motor with working condition self - adaptation ability provided by an embodiment of the present invention; Figure 2 FIG. is a flowchart of a control method of a servo motor with working condition self - adaptation ability provided by an embodiment of the present invention. Detailed Embodiments

[0016] In order to more clearly understand the above - mentioned objects, features and advantages of the present invention, the present invention will be further described in detail below with reference to the drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0017] In the following description, many specific details are set forth to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0018] In the description of the present invention, the term "a plurality of" refers to two or more, unless otherwise clearly defined. The orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Terms such as "connection", "installation", "fixation", etc. should all be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0019] In the description of this specification, the descriptions of terms such as "an embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0020] Next, a servo motor with working condition self-adaptive ability and its control method provided according to some embodiments of the present invention will be described with reference to the drawings.

[0021] As Figure 1 shown, a first aspect of the present invention proposes a servo motor with working condition self-adaptive ability, including a control unit, and the control unit is configured to: Monitor the working condition parameters of the servo motor, where the working condition parameters are the parameters reflecting the working state of the servo motor on the servo motor or the driving object of the servo motor; Identify the working condition change of the servo motor according to the change of the working condition parameters; When the working condition of the servo motor changes, identify the working condition change scenario of the servo motor; Adopt a working condition correction model matching the working condition change scenario to correct the working condition parameters of the servo motor, and the working condition correction model includes a control feedback period for performing control feedback and a stable control period for performing stable control 1. The first empirical function for initializing control parameters after a working condition change 2. For calculating the first empirical function 3. The second empirical function for calculating the correction amount of the working condition parameters corresponding to the output control parameters 4. And the maximum error of the second empirical function 5. .

[0022] The driving object of the servo motor includes an execution component connected to the main shaft of the servo motor and driven by the servo motor, such as a cutting tool of a numerical control machine tool, a robotic arm or a driving wheel of an industrial robot, or a nozzle of a 3D printer. The working condition parameters include, but are not limited to, the position of the driving object, the position / speed of the main shaft of the servo motor. The servo motor further includes a feedback unit and a driving unit. The feedback unit is used to collect and feedback the working condition parameters of the servo motor to the control unit, and the driving unit is used to drive the main shaft of the servo motor to move under the control of the control unit.

[0023] The working condition change refers to the change in the working conditions of the servo motor caused by the change in the load of the servo motor or the execution object of its host device. The working condition change scenario refers to the environmental scenario corresponding to the working condition change of the servo motor, which is usually related to the type of the host device of the servo motor, as well as information such as its working environment and working content. The host device of the servo motor refers to various mechanical devices installed with the servo motor, such as numerical control machine tools, industrial robots or logistics robots. When the degree of working condition change of the servo motor is not large, it usually does not affect the normal operation of the servo motor. When the working condition change of the servo motor is large, especially in some sudden working condition change scenarios, such as the change of machining materials of a numerical control machine tool, the change of the end load of an industrial robot or a logistics robot encountering a steep slope with a large gradient, etc., it will cause the working condition parameters of the servo motor to be abnormal, thus affecting the normal operation of the servo motor.

[0024] The working condition correction model is a correction parameter model pre-constructed for various working condition change scenarios to correct the change of working condition parameters in the corresponding working condition change scenarios. The control feedback period in the working condition correction model is the control feedback period, that is, within one control feedback period, the control unit of the servo motor collects feedback data from the feedback unit once and sends a control signal to the driving unit according to the feedback data, so that the driving unit drives the main shaft of the servo motor to rotate at the corresponding speed / rotation amount according to the control signal. The stable control period For a stable control period, that is, within a stable control period of the control unit of the servo motor, the operating condition parameters that abnormally change due to the change of the operating condition are corrected to a stable state under the expected value.

[0025] The first empirical function and the second empirical function are both empirical functions obtained by fitting the measurement data of the control parameters and operating condition parameters of the servo motor under various operating condition change scenarios under laboratory conditions. Specifically, the first empirical function is a control parameter correction function matching the operating condition change scenario, and is used to re-initialize the control parameters of the servo motor after the operating condition change according to the operating condition change scenario when the operating condition of the servo motor changes. The second empirical function is used to calculate, under the corresponding operating condition change scenario, the operating condition parameters expected by the servo motor in the next control feedback cycle when the control parameters calculated by the first empirical function are input to the servo motor in a control feedback cycle. The maximum error is, under laboratory conditions, the maximum value of the difference between the operating condition parameters calculated by the second empirical function and the operating condition parameters actually measured by the feedback unit after the control parameters are input to the servo motor under the corresponding operating condition change scenario.

[0026] Further, in the step of correcting the operating condition parameters of the servo motor by using the operating condition correction model matching the operating condition change scenario, the control unit is configured to: Obtain the parameter data of the servo motor before and after the operating condition change, and the parameter data includes control parameters and operating condition parameters; According to the parameter data of the servo motor before and after the operating condition change, the second control parameter of the servo motor after the operating condition change ; Input the second control parameter into the second empirical function to calculate the operating condition parameter correction amount corresponding to the second control parameter ; According to the maximum error of the second empirical function determine the operating condition parameter correction amount range corresponding to the second control parameter ; According to the correction amount range within the stable control period and with the control feedback period To control the feedback period, the operating condition parameters of the servo motor are corrected to the target values .

[0027] In the step of obtaining the first control parameter of the servo motor before the operating condition changes , the first control parameter is the control parameter carried by the control signal sent by the control unit of the servo motor to its drive unit in a control period before the start time . It should be noted that the control period before the start time and the control feedback period can be configured to the same value or different values

[0028] Furthermore, in the step of obtaining the parameter data of the servo motor before and after the operating condition changes, the control unit is configured to determine the time when the operating condition change of the servo motor is recognized as the start time ; obtain the first control parameter and the first operating condition parameter of the servo motor before the operating condition changes ; calculate the change value of the operating condition parameters of the servo motor at the start time .

[0029] Furthermore, in the step of calculating the change value of the operating condition parameters of the servo motor at the start time , the control unit is configured to obtain the first operating condition parameter of the servo motor in a control period before the start time through the feedback unit of the servo motor, and the second operating condition parameter of the servo motor at the start time ; calculate the difference between the second operating condition parameter and the first operating condition parameter as the change value of the operating condition parameters of the servo motor at the start time .

[0030] Furthermore, in the step of determining the second control parameter of the servo motor after the operating condition changes according to the parameter data of the servo motor before and after the operating condition changes, the control unit is configured to​ Input the first control parameter , the first operating condition parameter and the change value into the first empirical function to calculate the second control parameter of the servo motor after the change of the operating condition .

[0031] Furthermore, in the step of inputting the second control parameter into the second empirical function to calculate the correction amount of the operating condition parameter corresponding to the second control parameter , the control unit is configured to: Obtain the second operating condition parameter of the servo motor at the starting time through the feedback unit of the servo motor ; Input the first control parameter , the first operating condition parameter , the second operating condition parameter , the change value and the second control parameter into the second empirical function to calculate the correction amount of the operating condition parameter corresponding to the second control parameter ; .

[0032] Furthermore, in the step of determining the correction amount range of the operating condition parameter corresponding to the second control parameter according to the maximum error of the second empirical function , the control unit is configured to: Obtain the second operating condition parameter of the servo motor at the starting time through the feedback unit of the servo motor ; Calculate the lower bound of the correction amount range of the operating condition parameter corresponding to the second control parameter : ; ; Calculate the upper bound of the correction amount range of the operating condition parameter corresponding to the second control parameter :

[0033] . Furthermore, in the stable control period according to the correction amount range within the control feedback period using the control feedback period to correct the operating condition parameters of the servo motor to the target value in the step, the control unit is configured to input the second control parameter to the drive unit of the servo motor in the first control feedback period after the start time ; ; obtain the operating condition parameters of the first control feedback period through the feedback unit of the servo motor ; judge whether the operating condition parameters of the first control feedback period fall within the correction range ; when the operating condition parameters of the first control feedback period fall within the correction range , fit the first operating condition parameter curve and the second operating condition parameter curve for defining the correction range of the operating condition parameters within a stable control period using the control feedback period as the iteration period to perform iterative control on the servo motor, so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve ;

[0034] In the technical solution of the above embodiment, the time for inputting the second control parameter to the drive unit of the servo motor is the start time of the first control feedback period after the start time , and the time for obtaining the operating condition parameters is the end time of the first control feedback period after the start time .

[0035] The first operating condition parameter curve and the second operating condition parameter curve are function curves in an orthogonal coordinate system with the operating condition parameter axis as the first orthogonal axis and the time axis as the second orthogonal axis. The first operating condition parameter curve starts from the coordinate point in the orthogonal coordinate system and ends at the coordinate point in the orthogonal coordinate system; the second operating condition parameter curve starts from the coordinate point in the orthogonal coordinate system and also ends at the coordinate point in the orthogonal coordinate system. That is, as the time in the time axis advances, the correction range of the operating condition parameters defined between the first operating condition parameter curve and the second operating condition parameter curve is a gradually converging range

[0036] Further, both the first operating condition parameter curve and the second operating condition parameter curve are parabolas with the coordinate points in the orthogonal coordinate system as vertices, and the symmetry axes of the first operating condition parameter curve and the second operating condition parameter curve are straight lines passing through the coordinate points in the orthogonal coordinate system and perpendicular to the time axis.

[0037] In the step of performing iterative control on the servo motor with the control feedback period as the iteration period, so that the operating condition parameters of the servo motor converge to the target value within the limits of the first operating condition parameter curve and the second operating condition parameter curve In this step, the correction amount range of the current iteration period is updated according to the functions of the first operating condition parameter curve and the second operating condition parameter curve in each iteration period , so as to adjust the control signal according to the difference between the operating condition parameter in the feedback signal of the previous iteration period and the correction range boundary and , thereby gradually correcting the operating condition parameters of the servo motor so that the operating condition parameters are corrected to the target value . By adopting the technical solution of the above implementation manner, it can be ensured that the operating condition parameters of the servo motor always fall within the controllable range, and the convergence speed is controllable.

[0038] Further, after the step of judging whether the operating condition parameter of the first control feedback period falls within the correction amount range , the control unit is configured as follows: When the operating condition parameter of the first control feedback period does not fall within the correction amount range , a valid correction amount range is re-determined according to the boundary difference between the operating condition parameter and the correction amount range ; Match the valid operating condition change scenario corresponding to the valid correction amount range in the database; Load the operating condition correction model of the valid operating condition change scenario to re-execute the step of correcting the operating condition parameters of the servo motor by using the operating condition correction model matched with the operating condition change scenario.

[0039] In the technical solution of some embodiments of the present invention, in the step of re-determining a valid correction amount range according to the boundary difference between the operating condition parameter and the correction amount range , the control unit is configured as follows: Judge or ; When , let , let ; When , let , let .

[0040] In the technical solutions of some other embodiments of the present invention, in the step of re - determining a valid correction amount range according to the boundary difference between the working condition parameters and the correction amount range , the control unit is configured as: Judge or ; When , let , let ; When , let , let .

[0041] Furthermore, in the step of performing iterative control on the servo motor with the control feedback period as the iteration period, so that the working condition parameters of the servo motor converge to the target value within the range defined by the first working condition parameter curve and the second working condition parameter curve, the control unit is configured as: Calculate the number of iteration periods within a stable control period : ; Initialize the integer calculation variable ; During the iterative control process, let the value of be incremented by 1 for each iteration step, so that always represents the number of steps that have been iterated currently; For each iteration step, calculate the correction amount range of the current iteration period according to the functions of the first working condition parameter curve and the second working condition parameter curve; Obtain the working condition parameters of the current iteration period through the feedback unit of the servo motor ; According to the difference between the working condition parameters of the current iteration period and the boundary of the correction amount range of the current iteration period, adjust the The control parameters for one iteration cycle.

[0042] In the technical solution of the above embodiment, is the modulo symbol, indicating divided by the case where the remainder is 0.

[0043] Similarly, indicating divided by the case where the remainder is not 0. is the floor symbol, indicating the integer part of the quotient of

[0044] In the technical solution of the above embodiment, represents the lower bound of the correction amount range in the th iteration cycle, represents the upper bound of the correction amount range in the th iteration cycle.

[0045] In the technical solution of some embodiments of the present invention, the operating condition correction model further includes a control parameter correction step . In the step of adjusting the control parameters for the th iteration cycle according to the difference between the operating condition parameters of the current iteration cycle and the boundary of the correction amount range of the current iteration cycle , the control unit is configured to: Determine whether the operating condition parameters of the current iteration cycle fall within the correction amount range of the current iteration cycle ; When the operating condition parameters of the current iteration cycle fall within the correction amount range of the current iteration cycle , calculate the difference between the operating condition parameters of the current iteration cycle and the boundary value of the correction amount range of the current iteration cycle : ; ; Compare with ; When , let ; When , let ; When , let .

[0046] in For the The control parameters of the iteration cycle are For the The control parameters of the iteration cycle, and so on.

[0047] Further, in the step of identifying the operating condition change of the servo motor according to the change of the operating condition parameter, the control unit is configured as follows: Read pre-configured operating parameter change thresholds ; Acquire a control instruction sent by the control unit of the servo motor to the drive unit of the servo motor in the last control feedback cycle, wherein the control instruction includes the third control parameter of the last control feedback cycle. , and the current control feedback cycle and the third control parameter The target value of the corresponding operating parameters ; Obtain the working condition parameters of the current control feedback cycle through the feedback unit of the servo motor ; Calculate the operating parameters of the current control feedback cycle With the target value The difference: ; Determine the difference Is it greater than the operating parameter change threshold? ; When the difference Greater than the operating parameter change threshold When the operating condition of the servo motor changes, it is determined that the operating condition of the servo motor changes.

[0048] Furthermore, before the step of identifying the operating condition change scenario of the servo motor, the control unit is configured to: Configuring in a database the type of the host device of the servo motor and the operating parameter change characteristics of the host device of the servo motor under various operating condition change scenarios; The step of identifying the operating condition change scenario of the servo motor specifically includes: Extracting the variation characteristics of the operating parameters of the servo motor; Matching the operating parameter change characteristics of the servo motor with the operating parameter change characteristics of various operating condition change scenarios under the corresponding host device type in the database; The operating condition change scenario of the servo motor is identified according to the matching result.

[0049] Specifically, the variation characteristics of the operating conditions parameters of the servo motor refer to the variation amplitude characteristics and variation frequency characteristics of the operating conditions parameters of the servo motor over a period of time, which are related to the type of the host device of the servo motor, as well as information such as its working environment and working content. When the operating conditions of the servo motor change, the operating conditions change scenario can usually be reflected by specific variation characteristics of the operating conditions parameters.

[0050] As Figure 2 shown, the second aspect of the present invention proposes a control method for a servo motor with operating conditions self - adaptation ability, including: Monitoring the operating conditions parameters of the servo motor, where the operating conditions parameters are the parameters reflecting the working state of the servo motor on the servo motor or the driven object of the servo motor; Identifying the change of the operating conditions of the servo motor according to the change of the operating conditions parameters; When the operating conditions of the servo motor change, identifying the operating conditions change scenario of the servo motor; Adopting an operating conditions correction model matching the operating conditions change scenario to correct the operating conditions parameters of the servo motor, where the operating conditions correction model includes a control feedback period for performing control feedback 、a stable control period for performing stable control 、a first empirical function for initializing the control parameters after the change of the operating conditions 、a second empirical function for calculating the correction amount of the operating conditions parameters corresponding to the control parameters output by the first empirical function , and the maximum error of the second empirical function , as well as the maximum error of the second empirical function . .

[0051] The driven object of the servo motor includes an execution component connected to the main shaft of the servo motor and driven by the servo motor, such as a cutting tool of a numerical control machine tool, a robotic arm or a driving wheel of an industrial robot, or a nozzle of a 3D printer, etc. The operating conditions parameters include, but are not limited to, the position of the driven object, the position / rotation speed of the main shaft of the servo motor.

[0052] The change in operating conditions refers to the change in the working conditions of the servo motor caused by the change in the load of the servo motor or the execution object of its host device. The operating condition change scenario refers to the environmental scenario corresponding to the change in the operating conditions of the servo motor, which is usually related to the type of the host device of the servo motor, as well as information such as its working environment and working content. The host device of the servo motor refers to various mechanical devices installed with the servo motor, such as numerically controlled machine tools, industrial robots, or logistics robots, etc. When the degree of change in the operating conditions of the servo motor is not significant, it usually does not affect the normal operation of the servo motor. When the change in the operating conditions of the servo motor is large, especially in some sudden operating condition change scenarios, such as the change of the machining material of a numerically controlled machine tool, the change of the end load of an industrial robot, or a logistics robot encountering a steep slope with a large gradient, etc., it will cause the operating condition parameters of the servo motor to be abnormal, thus affecting the normal operation of the servo motor.

[0053] The operating condition correction model is a correction parameter model pre-constructed for various operating condition change scenarios to correct the change in operating condition parameters under the corresponding operating condition change scenarios. The control feedback period in the operating condition correction model is the control feedback period, that is, within one control feedback period of the control unit of the servo motor, it collects feedback data from the feedback unit once and issues a control signal to the drive unit according to the feedback data, so that the drive unit drives the main shaft of the servo motor to rotate at the corresponding rotational speed / rotation amount according to the control signal. The stable control period in the operating condition correction model is the stable control period, that is, within one stable control period of the control unit of the servo motor, it corrects the operating condition parameters that have changed abnormally due to the change in operating conditions to the stable state under the expected value.

[0054] The first empirical function and the second empirical function are both empirical functions obtained by fitting the measurement data of the control parameters and operating condition parameters of the servo motor under various operating condition change scenarios under laboratory conditions. Specifically, the first empirical function is a control parameter correction function matching the operating condition change scenario, which is used to re-initialize the control parameters of the servo motor after the operating condition change according to the operating condition change scenario. The second empirical function is used to calculate the expected operating condition parameters of the servo motor in the next control feedback period when inputting the control parameters calculated by the first empirical function to the servo motor within one control feedback period under the corresponding operating condition change scenario. The maximum error Under laboratory conditions, according to the servo motor after inputting control parameters in the corresponding working condition change scenario, through the second empirical function Calculate the maximum value of the difference between the working condition parameters obtained through calculation and the working condition parameters actually measured by the feedback unit

[0055] Further, the steps of correcting the working condition parameters of the servo motor by using the working condition correction model matching the working condition change scenario specifically include Obtain the parameter data of the servo motor before and after the working condition change, and the parameter data includes control parameters and working condition parameters According to the parameter data of the servo motor before and after the working condition change, the second control parameter of the servo motor after the working condition change ; Input the second control parameter Into the second empirical function To calculate the working condition parameter correction amount corresponding to the second control parameter ; ; According to the maximum error of the second empirical function Determine the working condition parameter correction amount range corresponding to the second control parameter ; ; ; According to the correction amount range Within the stable control period Take the control feedback period As the control feedback period, correct the working condition parameters of the servo motor to the target value ;

[0056] In the step of obtaining the first control parameter of the servo motor before the working condition change The first control parameter Is the control parameter carried by the control signal sent by the control unit of the servo motor to its drive unit in the control cycle before the start time . It should be noted that the control cycle before the start time And the control feedback period Can be configured to the same value or different values

[0057] Further, the steps of obtaining the parameter data of the servo motor before and after the working condition change specifically include Determine the time when the working condition change of the servo motor is recognized as the start time ; Obtaining the first control parameter of the servo motor before the operating condition changes And the first condition parameters ; Calculate the operating parameters of the servo motor at the start time Time-varying value .

[0058] Further, the operating parameters of the servo motor are calculated at the starting time Time-varying value The steps specifically include: The feedback unit of the servo motor obtains the servo motor at the start time The first operating condition parameter of the previous control cycle and the servo motor at the start time The second operating condition parameters at time ; Calculate the second working condition parameters With the first operating condition parameters The difference is used as the working parameter of the servo motor At the starting time Time-varying value .

[0059] Further, according to the parameter data of the servo motor before and after the working condition changes, the second control parameter of the servo motor after the working condition changes The steps specifically include: The first control parameter , the first operating condition parameter And the change value Enter the first empirical function Calculate the second control parameter of the servo motor after the working condition changes .

[0060] Furthermore, when the second control parameter Enter the second empirical function To calculate the second control parameter Corresponding operating parameter correction The steps specifically include: The feedback unit of the servo motor obtains the servo motor at the start time The second operating condition parameters at time ; The first control parameter , the first operating condition parameter The second operating condition parameter , the change value and the second control parameter input the second empirical function to calculate the second control parameter corresponding working condition parameter correction amount .

[0061] Furthermore, according to the second empirical function the maximum error determine the second control parameter corresponding working condition parameter correction amount range The steps specifically include: Obtain the second working condition parameter of the servo motor at the start time through the feedback unit of the servo motor ; Calculate the lower bound of the working condition parameter correction amount range corresponding to the second control parameter : ; Calculate the upper bound of the working condition parameter correction amount range corresponding to the second control parameter : .

[0062] Furthermore, according to the correction amount range within the stable control period with the control feedback period as the control feedback period, correct the working condition parameters of the servo motor to the target value The steps specifically include: At the first control feedback period after the start time input the second control parameter to the drive unit of the servo motor ; Obtain the working condition parameters of the first control feedback period through the feedback unit of the servo motor ; Judge whether the working condition parameters of the first control feedback period fall within the correction amount range ; When the working condition parameters of the first control feedback period fall within the correction amount range fit the first working condition parameter curve and the second working condition parameter curve for defining the working condition parameter correction range within a stable control period; With the control feedback period Iteratively control the servo motor for each iteration period so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve 。

[0063] In the technical solution of the above embodiment, input the second control parameter to the drive unit of the servo motor at the moment which is the start moment of the first control feedback period after the start time , and obtain the operating condition parameters at the moment which is the end moment of the first control feedback period after the start time .

[0064] The first operating condition parameter curve and the second operating condition parameter curve are function curves in an orthogonal coordinate system with the operating condition parameter axis as the first orthogonal axis and the time axis as the second orthogonal axis. The first operating condition parameter curve starts from the coordinate point in the orthogonal coordinate system and ends at the coordinate point in the orthogonal coordinate system; the second operating condition parameter curve starts from the coordinate point in the orthogonal coordinate system and also ends at the coordinate point in the orthogonal coordinate system. That is, as the time in the time axis advances, the range of operating condition parameter correction defined between the first operating condition parameter curve and the second operating condition parameter curve is a gradually converging range

[0065] Further, both the first operating condition parameter curve and the second operating condition parameter curve are parabolas with the coordinate point in the orthogonal coordinate system as the vertex, and the symmetry axes of the first operating condition parameter curve and the second operating condition parameter curve are straight lines passing through the coordinate point in the orthogonal coordinate system and perpendicular to the time axis

[0066] In the step of iteratively controlling the servo motor for each iteration period so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve , update the correction amount range of the current iteration period according to the functions of the first operating condition parameter curve and the second operating condition parameter curve for each iteration period , and adjust the control signal according to the difference between the operating condition parameters in the feedback signal of the previous iteration period and the correction range boundaries and so as to gradually correct the operating condition parameters of the servo motor to the target value By adopting the technical solution of the above implementation mode, it can be ensured that the operating parameters of the servo motor always fall within the controllable range and the convergence speed is controllable.

[0067] Furthermore, in determining the operating parameters of the first control feedback cycle Whether it falls within the correction range After the steps within, it also includes: When the operating parameters of the first control feedback cycle Does not fall within the correction range Within, according to the working condition parameters With the correction range The boundary difference of the redefines an effective correction range ; Match the effective correction range in the database Corresponding effective working condition change scenarios; The operating condition correction model of the effective operating condition change scenario is loaded to re-execute the step of correcting the operating condition parameters of the servo motor using the operating condition correction model matching the operating condition change scenario.

[0068] In the technical solutions of some embodiments of the present invention, according to the operating condition parameters With the correction range The boundary difference of the redefines an effective correction range In the step, the control unit is configured to: judge still ; when season ,make ; when season ,make .

[0069] In the technical solutions of other embodiments of the present invention, according to the operating condition parameters With the correction range The boundary difference of the redefines an effective correction range In the step, the control unit is configured to: judge still ; when season ,make ; when season ,make 。

[0070] Further, taking the control feedback period as the iteration period, iterative control is performed on the servo motor so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve The steps specifically include: Calculate the number of iteration periods within a stable control period : ; Initialize the integer calculation variable ; During the iterative control process, increment the value of by 1 for each iteration step, so that the value of always represents the number of steps that have been iterated currently; For each iteration step, calculate the correction amount range of the current iteration period according to the functions of the first operating condition parameter curve and the second operating condition parameter curve ; Obtain the operating condition parameters of the current iteration period through the feedback unit of the servo motor ; According to the operating condition parameters of the current iteration period and the boundary of the correction amount range of the current iteration period adjust the control parameters of the th iteration period.

[0071] In the technical solution of the above embodiment, is the modulo symbol, represents divided by with a remainder of 0.

[0072] Similarly, represents divided by with a non-zero remainder. is the floor symbol, represents the integer part of the quotient of.

[0073] In the technical solution of the above embodiment, represents the lower bound of the correction amount range in the th iteration period, represents the upper bound of the correction amount range in the th iteration period.

[0074] In the technical solution of some embodiments of the present invention, the operating condition correction model further includes a control parameter correction step size and adjusting the control parameter of the nth iteration cycle according to the difference between the working condition parameters of the current iteration cycle and the boundary of the correction amount range of the current iteration cycle specifically includes: judging whether the working condition parameters of the current iteration cycle fall within the correction amount range of the current iteration cycle ; when the working condition parameters of the current iteration cycle fall within the correction amount range of the current iteration cycle calculate the difference between the working condition parameters of the current iteration cycle and the boundary value of the correction amount range of the current iteration cycle : ; ; compare with to determine their magnitudes; when let ; when let ; when let .

[0075] where is the control parameter of the nth iteration cycle, is the control parameter of the th iteration cycle, and so on.

[0076] Further, the steps of identifying the working condition change of the servo motor according to the change of the working condition parameters specifically include: reading the pre-configured threshold value of the working condition parameter change ; obtaining the control instruction sent by the control unit of the servo motor to the drive unit of the servo motor in the previous control feedback cycle, the control instruction includes the third control parameter of the previous control feedback cycle , and the target value of the working condition parameter corresponding to the third control parameter in the current control feedback cycle ; acquiring the working condition parameters of the current control feedback cycle through the feedback unit of the servo motor ; calculating the working condition parameters of the current control feedback cycle ​The difference from the target value is: ; Determine whether the difference is greater than the threshold of the change in operating condition parameters ; When the difference is greater than the threshold of the change in operating condition parameters it is determined that a change in the operating condition of the servo motor has occurred.

[0077] Furthermore, before the step of identifying the operating condition change scenario of the servo motor, it further includes: Configure the type of the host device of the servo motor and the characteristics of the change in operating condition parameters of the host device of the servo motor under various operating condition change scenarios in the database; The step of identifying the operating condition change scenario of the servo motor specifically includes: Extract the characteristics of the change in operating condition parameters of the servo motor; Match the characteristics of the change in operating condition parameters of the servo motor with the characteristics of the change in operating condition parameters of various operating condition change scenarios corresponding to the type of the host device in the database; Identify the operating condition change scenario of the servo motor according to the matching result.

[0078] Specifically, the characteristics of the change in operating condition parameters of the servo motor are the characteristics of the change amplitude and the change frequency of the operating condition parameters of the servo motor over a period of time, which are related to the type of the host device of the servo motor, as well as information such as its working environment and working content. When a change in the operating condition of the servo motor occurs, its operating condition change scenario can usually be reflected by specific characteristics of the change in operating condition parameters.

[0079] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the element.

[0080] As described above with reference to the embodiments of the present invention, these embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the above description. These embodiments are selected and specifically described in this specification in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and its modifications based on the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A servo motor with working condition self - adapting ability, characterized in that, Comprising a control unit configured to: Monitor the operating condition parameters of the servo motor, where the operating condition parameters are parameters reflecting the operating state of the servo motor on the servo motor or the driven object of the servo motor; Identify the change in the operating condition of the servo motor according to the change in the operating condition parameters; When the operating condition of the servo motor changes, identify the operating condition change scenario of the servo motor; Modify the operating condition parameters of the servo motor by using an operating condition correction model that matches the operating condition change scenario, where the operating condition correction model includes a control feedback period for performing control feedback , a stable control period for performing stable control , a first empirical function for initializing the control parameters after the change of the operating condition , a second empirical function for calculating the correction amount of the operating condition parameters corresponding to the control parameters output by the first empirical function , and the maximum error of the second empirical function , and the maximum error of the second empirical function . .

2. A control method for a servo motor with working condition self - adapting ability, characterized in that, Including: Monitor the operating condition parameters of the servo motor, where the operating condition parameters are parameters reflecting the operating state of the servo motor on the servo motor or the driven object of the servo motor; Identify the change in the operating condition of the servo motor according to the change in the operating condition parameters; When the operating condition of the servo motor changes, identify the operating condition change scenario of the servo motor; Modify the operating condition parameters of the servo motor by using an operating condition correction model that matches the operating condition change scenario, where the operating condition correction model includes a control feedback period for performing control feedback , a stable control period for performing stable control , a first empirical function for initializing control parameters after an operating condition change , a second empirical function for calculating the correction amount of the operating condition parameters corresponding to the control parameters output by the first empirical function , and the maximum error of the second empirical function , as well as the maximum error of the second empirical function .

3. The control method of the servo motor with working condition self - adaptation ability according to claim 2, characterized in that, The steps of correcting the operating condition parameters of the servo motor by using the operating condition correction model matching the operating condition change scenario specifically include: Obtain the parameter data of the servo motor before and after the operating condition change, where the parameter data includes control parameters and operating condition parameters; The second control parameter of the servo motor after the operating condition change according to the parameter data of the servo motor before and after the operating condition change ; Input the second control parameter into the second empirical function to calculate the correction amount of the operating condition parameter corresponding to the second control parameter ; According to the second empirical function the maximum error to determine the second control parameter corresponding correction amount range of the operating condition parameter ; According to the correction amount range During the stable control period within, with the control feedback period as the control feedback period, correct the operating condition parameters of the servo motor to the target value .

4. The control method of the servo motor with working condition self-adaptive ability according to claim 3, characterized in that, The steps of obtaining the parameter data of the servo motor before and after the operating condition change specifically include: Determine the time when the recognized operating condition change of the servo motor occurs as the starting time ; Obtain the first control parameter of the servo motor before the working condition changes and the first working condition parameter ; Calculate the change value of the operating condition parameters of the servo motor at the start time per unit time .

5. The control method of the servo motor with working condition self - adapting ability according to claim 4, characterized in that, According to the range of the correction amount within the stable control period using the control feedback period as the control feedback period, correcting the operating condition parameters of the servo motor to the target value The steps specifically include: At the starting time input the second control parameter into the drive unit of the servo motor in the first control feedback cycle after the moment ; Obtain the operating condition parameters of the first control feedback cycle through the feedback unit of the servo motor ; Judge whether the operating condition parameters of the first control feedback cycle fall within the range of the correction amount ; When the operating condition parameters of the first control feedback cycle fall within the correction amount range a first operating condition parameter curve and a second operating condition parameter curve for defining the correction range of the operating condition parameters within a stable control cycle are fitted; Using the control feedback period as the iteration period to perform iterative control on the servo motor, so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve .

6. The control method of the servo motor with working condition self-adaptive ability according to claim 5, characterized in that, Both the first operating condition parameter curve and the second operating condition parameter curve are parabolas with the coordinate point as the vertex. The symmetry axes of the first operating condition parameter curve and the second operating condition parameter curve are straight lines passing through the coordinate point and perpendicular to the time axis.

7. The control method of the servo motor with working condition self - adaptation ability according to claim 5, characterized in that, After the step of determining whether the operating condition parameters of the first control feedback cycle fall within the correction amount range it further includes: When the operating condition parameters of the first control feedback cycle do not fall within the correction amount range When that is the case, based on the operating condition parameters and the boundary difference between the operating condition parameters and the correction amount range, re-determine a valid correction amount range ; Match the effective correction amount range in the database The corresponding effective operating condition change scenario; Load the operating condition correction model of the effective operating condition change scenario to re - execute the steps of correcting the operating condition parameters of the servo motor by using the operating condition correction model matching the operating condition change scenario.

8. The control method of the servo motor with working condition self-adaptive ability according to claim 5, characterized in that, Using the control feedback period as the iteration period to perform iterative control on the servo motor, so that the operating condition parameters of the servo motor converge to the target value within the range defined by the first operating condition parameter curve and the second operating condition parameter curve The steps specifically include: Calculate the number of iteration cycles within a stable control period : ； Initialize integer calculation variables ; In the iterative control process, let increase by 1 for each iteration step, so that always represents the number of steps that have been iterated currently; At each iteration step, calculate the correction amount range of the current iteration cycle according to the functions of the first operating condition parameter curve and the second operating condition parameter curve ; Obtain the operating condition parameters of the current iteration cycle through the feedback unit of the servo motor ; According to the operating condition parameters of the current iteration cycle and the correction amount range of the current iteration cycle to adjust the control parameter of the th iteration cycle based on the difference from the boundary 9. The control method of the servo motor with working condition self-adaptive ability according to claim 2, characterized in that, The steps of identifying the change in the operating condition of the servo motor according to the change in the operating condition parameters specifically include: Read the pre-configured threshold for changes in operating conditions ; Obtain the control instruction sent by the control unit of the servo motor to the drive unit of the servo motor in the previous control feedback cycle, where the control instruction includes the third control parameter in the previous control feedback cycle , and the target value of the operating condition parameter corresponding to the third control parameter in the current control feedback cycle ; Obtain the operating condition parameters of the current control feedback cycle through the feedback unit of the servo motor ; Calculate the operating condition parameters of the current control feedback cycle and the target value for the difference: ； Determine the difference is greater than the threshold value of the change in the operating condition parameter ; When the difference is greater than the threshold value of the operating condition parameter change it is determined that the operating condition of the servo motor has changed.

10. The control method of the servo motor with working condition self - adapting ability according to claim 2, characterized in that, Before the step of identifying the operating condition change scenario of the servo motor, it further includes: Configure the type of the host device of the servo motor and the characteristics of the change in the operating condition parameters of the host device of the servo motor under various operating condition change scenarios in the database; The steps of identifying the operating condition change scenario of the servo motor specifically include: Extract the characteristics of the change in the operating condition parameters of the servo motor; Match the characteristics of the change in the operating condition parameters of the servo motor with the characteristics of the change in the operating condition parameters of various operating condition change scenarios under the corresponding host device type in the database; Identify the operating condition change scenario of the servo motor according to the matching result.

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