Nonlinear adaptive AC servo motor angular position control method and system

Abstract

The present invention relates to a nonlinear adaptive AC servo motor angular position control method and system, which includes the following method: obtain original motor rotor angular position data; input the original motor rotor angular position data into a motor rotor angular position control module; at the same time, the motor rotor position data generates motor rotor angular acceleration data through second-order time differentiation; input the motor rotor angular acceleration data and the output of the motor rotor angular position control module into an incremental inverse dynamics control module at the same time; input the output of the incremental inverse dynamics control module into a motor current control module. The present invention does not require a motor model and a motor load model required for setting the controller parameters, so it can solve the problem of the difficulty of distinguishing the motor model and the load model in the existing servo motor control technology and the technical problem of setting the time-varying parameters of the controller. In the practical situation where the existing technology cannot effectively solve the above difficulties and problems, the present invention provides a very simple, effective and high-performance nonlinear adaptive control method.

Description

[Technical Field]

[0001] The present invention relates to the field of motor control, and more particularly to a method and system for nonlinear adaptive AC servo motor angular position control. [Background technology]

[0002] With the continuous development of intelligent technology, people increasingly use intelligent devices in their lives, work, and learning. The use of intelligent technology has improved people's quality of life and the efficiency of their learning and work. In the field of motor control, the motor system is inherently a nonlinear, time-varying, and uncertain system, which requires the use of nonlinear and adaptive control algorithms in the design of the control system.

[0003] Currently, all motor servo control systems use traditional PID control algorithms. PID control algorithms are based on linear systems, and using a PID algorithm to control a nonlinear servo motor poses a challenge: how to set the PID proportional, integral, and derivative parameters. Due to the nonlinearity, time-varying nature of the motor system, and uncertainty, offline or online identification of a nonlinear or linearized model of the motor and load is essential. The acquired motor and load models are used to set the PID parameters in real time or in sections. Traditional PID algorithms maintain constant parameters throughout the entire control process. However, in actual use, the entire controlled system cannot be predicted in advance, so the system cannot achieve high-performance control with fixed PID parameters. While model identification can achieve relatively good control performance, model identification, especially online model identification, significantly increases system complexity. Furthermore, model identification cannot guarantee accurate model and model parameter acquisition, making it difficult for such adaptive control systems to obtain industrial certification. Similarly, other intelligent control methods, including adaptive or fuzzy control, sliding mode control, neural network-based control, model reference adaptation, etc., also have problems in that they cannot guarantee algorithm stability and stable operation in any load interference environment.

[0004] Currently, no effective solution has been proposed for the above problems. Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention aims to provide a nonlinear adaptive AC servo motor angular position control method and system, thereby solving technical problems in current servo motor control technology, such as the difficulty of distinguishing between the motor model and the load model, and the time-varying parameter setting of the controller. [Means for solving the problem]

[0006] In one embodiment of the present invention, the present invention provides an adaptive AC servo motor angular position control method, including: Obtain motor rotor angular position data; Compare the motor rotor angular position data with the motor rotor angular position required by the user, and input the difference into the motor rotor angular position control module; taking a second-order time derivative with said motor rotor angular position data to generate motor rotor angular acceleration data; The motor rotor angular acceleration data and the output of the motor rotor angular position control module are simultaneously input into an incremental inverse dynamics control module; The output of the incremental inverse dynamics control module is input to the motor current control module.

[0007] The motor rotor angular position data is obtained from a motor rotor rotational angle position encoder.

[0008] The expression of the incremental inverse dynamics control module is as follows: JPEG0007747893000001.jpg26170In the formula, Δi q is the output current increment of the incremental inverse dynamics control module, and i q is the output current of the incremental inverse dynamics control module, and i q0 is the sampling value before the current output of the incremental inverse dynamics control module, J is the moment of inertia, p is the number of motor poles, and ψ m is the permanent magnet magnetic flux, L q is the q-axis inductance, L d is the d-axis inductance, i d is the d-axis current, v θ is the virtual control variable in inverse dynamics control, JPEG0007747893000002.jpg19166 is the second-order time derivative of the motor rotor rotation angle at the sampling point.

[0009] Furthermore, the AC servo motor control also includes a motor current control module.

[0010] The present invention also discloses a non-volatile storage medium, which includes a storage program, and wherein, during execution of the program, a device in which the non-volatile storage medium is controlled executes any of the above methods.

[0011] The present invention further discloses an electronic device, comprising a processor and a memory; the memory storing computer readable instructions, the processor being adapted to execute the computer readable instructions, wherein the computer readable instructions, when executed, perform any of the methods described above.

[0012] In another embodiment of the present invention, a non-volatile storage medium is provided, the non-volatile storage medium containing a storage program, wherein when the program is executed, an apparatus in which the non-volatile storage medium is configured to control performs a non-linear adaptive AC servo motor angular position control method.

[0013] Another embodiment of the present invention provides an electronic device including a processor and a memory; the memory stores computer-readable instructions, and the processor is adapted to execute the computer-readable instructions, wherein, when the computer-readable instructions are executed, the method for adaptive AC servo motor angular position control is performed.

[0014] In an embodiment of the present invention, the required motor system and load models are replaced by the second-order time derivative of the motor position (motor angular acceleration), eliminating the need for system and load models in inverse dynamics control, and resolving the technical problems of difficult discrimination between the motor model and the load model in existing servo motor control technology and the time-varying parameter setting of the controller. [Brief explanation of the drawings]

[0015] The drawings described herein are intended to provide a further understanding of the present invention and are a part of the construction of this application, and the illustrative embodiments of the present invention and the description thereof are used to interpret the present invention and are not intended to unduly limit the present invention. [Figure 1] FIG. 1 is a process diagram of a nonlinear adaptive AC servo motor angular position control method according to an embodiment of the present invention. [Figure 2] FIG. 2 is a structural diagram of a nonlinear adaptive AC servo motor angular position control method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] In order to allow those skilled in the art to further understand the technology of the present invention, the technology of the embodiments of the present invention will be clearly and completely described below with reference to the drawings of the embodiments of the present invention. Obviously, the described embodiments are only some examples of the present invention, and are not all examples. Based on the embodiments of the present invention, all other examples that can be obtained by ordinary skilled in the art without creative efforts should be included within the protection scope of the present invention.

[0017] It should be noted that terms such as "first," "second," and the like in the present specification and claims, as well as in the drawings, are used to distinguish between similar objects and do not necessarily describe a particular order or chronology. Such terms, as used herein, are interchangeable under appropriate circumstances, and it should be understood that the embodiments of the present invention described herein may be practiced in orders other than those illustrated or described herein. Furthermore, the terms "comprise" and "have," and any variations thereof, are intended to be non-exclusive inclusive. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not limited to the explicitly listed steps or units, but may also include steps or units that are inherent in the process, method, product, or apparatus, even if not explicitly listed.

[0018] In accordance with an embodiment of the present invention, there is provided an embodiment of a nonlinear adaptive AC servo motor angular position control method, and it should be noted that the steps illustrated in the flowcharts of the accompanying drawings may be performed by a computer system capable of executing computer instructions, and that although the flowcharts are presented in a logical order, in some cases the steps may be performed in an order different from that shown.

[0019] FIG. 1 is a flowchart of a nonlinear adaptive AC servo motor angular position control method according to an embodiment of the present invention. As shown in FIG. 1, the method includes the following steps: Step S100: obtain motor rotor angular position data; Step S200: Compare the motor rotor angular position data with the motor rotor angular position required by the user, and input the difference into the motor rotor angular position control module; Step S300: obtain a second-order time derivative of the motor rotor angular position data to generate motor rotor angular acceleration data; Step S400: input the motor rotor angular acceleration data and the output of the motor rotor angular position control module into the incremental inverse dynamics control module simultaneously; Step S500: input the output of the incremental inverse dynamics control module into the motor current control module.

[0020] FIG. 2 is a block diagram of an adaptive AC servo motor angular position control system according to an embodiment of the present invention. As shown in FIG. 2, the system includes: Obtain motor rotor angular position data; Compare the motor rotor angular position data with the motor rotor angular position required by the user, and input the difference into the motor rotor angular position control module;

[0021] taking a second-order time derivative with said motor rotor angular position data to generate motor rotor angular acceleration data; The motor rotor angular acceleration data and the output of the motor rotor angular position control module are simultaneously input into an incremental inverse dynamics control module; The output of the incremental inverse dynamics control module is input to the motor current control module.

[0022] Specifically, the motor angular position control module has proportional, integral and differential functions.

[0023] The expression of the incremental inverse dynamics control module is as follows: JPEG0007747893000003.jpg19170In the formula, Δi q is the output current increment of the incremental inverse dynamics control module, and i q is the output current of the incremental inverse dynamics control module, and i q0 is the sampling value before the current output of the incremental inverse dynamics control module, J is the moment of inertia, p is the number of motor poles, and ψ m is the permanent magnet magnetic flux, L q is the q-axis inductance, L d is the d-axis inductance, i d is the d-axis current, v θ is the virtual control variable in inverse dynamics control, JPEG0007747893000004.jpg22135 is the second-order time derivative of the motor rotor rotation angle at the sampling point.

[0024] Specifically, the mathematical model of the adaptive AC servo motor angular position control system according to the embodiment of the present invention includes a current model, a velocity model and a position model, for example, the three mathematical models are as follows:

[0025] Current Model: JPEG0007747893000005.jpg39170

[0026] Angular velocity model: JPEG0007747893000006.jpg15170

[0027] Angular position model: JPEG0007747893000007.jpg21170

[0028] In the above formulas (1) to (4), the variables and parameters are defined as follows: JPEG0007747893000008.jpg45170

[0029] Among them, the angular velocity model (4) and the angular position model (5) can be combined and written as: JPEG0007747893000009.jpg16170

[0030] It should be noted that permanent magnet synchronous motors (PMSMs), abbreviated as PMSM, are synchronous motors with permanent magnets wound around the rotor instead of the rotor itself. PMSMs can be classified as radial, axial, or transverse types based on the magnetic flux mode, determined by the component layout. Each type of PMSM varies in efficiency, volume, weight, and operating speed. The operating principle of a PMSM is similar to that of an electric excitation synchronous motor, but the magnetic flux provided by a permanent magnet material is used instead of the excitation winding of the latter, resulting in a simpler motor structure. A PMSM is a synchronous motor that generates a synchronous rotating magnetic field using permanent magnet excitation. The permanent magnet material serves as the rotor, generating a rotating magnetic field. The three-phase stator winding senses three-phase symmetrical currents through armature reaction under the action of the rotating magnetic field. Here, the kinetic energy of the rotor is converted into electrical energy, and the PMSM is used as a generator; in addition, when three-phase symmetrical current flows on the stator side, the three-phase stator has a spatial position difference of 12°, so the three-phase stator current generates a rotating magnetic field in space, and the rotor moves under the influence of electromagnetic force in the rotating magnetic field, and here, electrical energy is converted into kinetic energy, and the PMSM is used as a motor.

[0031] Unknown parameters and inputs "B, R, T LDue to the existence of ", the current model and speed model are nonlinear and uncertain, and PID control based on linear systems cannot guarantee high performance. PID stands for Proportional, Integral, and Differential. PID control algorithms combine proportional, integral, and differential controls into one. This is the most mature and widely used control algorithm for continuous systems. This control algorithm emerged in the 1930s and 1940s and is suitable for situations where the controlled object model is not clearly understood. Practical experience and theoretical analysis have shown that this control method can achieve satisfactory results in many industrial processes. The essence of PID control is that it operates on input deviation values, performing calculations based on proportional, integral, and differential function relationships, and then using the calculation results to control the output. Furthermore, in PID control, closed-loop control is a control method that makes corrections based on output feedback from the controlled object. When a deviation between actual and planned values ​​is measured, corrections are made according to a quota or standard. For example, to control the speed of a motor, a sensor is needed to measure the speed and feed the result back to the control route. When it comes to closed-loop control algorithms, we need to mention PID, which is the simplest closed-loop control algorithm. PID stands for Proportional, Integral, and Differential Coefficient, and each represents three types of control algorithms. By combining these three algorithms, it is possible to effectively correct the deviation of the controlled object and reach a stable state.

[0032] The embodiment of the present invention relies on the principle of cascade inverse dynamics control, and does not need to realize complete linearization of the system by controlling the nonlinear dynamics and kinematic model that requires inverse dynamics control. The specific realization steps of the embodiment are to first obtain the inverse dynamics control using the time sampling of Equation 5: JPEG0007747893000010.jpg14170

[0033] Incremental inverse dynamics control is possible under high-speed sampling conditions (10 kHz), which all servo motors already have: JPEG0007747893000011.jpg17170

[0034] From this result, it is clear that the motor rotation angle θ and the time derivative function that calculates the rotation angle The resulting control algorithm is based on a complex and uncertain unknown impedance B and an unknown motor load T. L The time derivative replaces the role of controller adaptation that the model plays in the inverse dynamics controller. q Since the motor angular position system is fully linearized and normalized, Δi q Inverse dynamics virtual control in v θ can be applied to determine the parameters of PID control.

[0035] Since the relative degree of (2) is 2, the virtual control v θ teeth: JPEG0007747893000013.jpg25170 Provided by user.

[0036] The embodiment of the present invention has the following features: 1. No adaptive control of the motor model is required; 2. Nonlinear control; 3. The control system is not affected by uncertain system parameters; 4. The control system is not affected by uncertain external interference; 5. The control system can achieve closed-loop stability and high-performance control under any realistic load interference conditions; 6. The control algorithm is simple and easy to implement.

[0037] Through the above embodiment, the technical problems of the difficulty in distinguishing between the motor model and the load model in the existing servo motor control technology and the time-varying parameter setting of the controller are solved.

[0038] The order of the above embodiments of the present invention is for illustrative purposes only and does not represent the superiority or inferiority of the embodiments.

[0039] In the above embodiments of the present invention, the description of each embodiment has its own emphasis, and for the parts not described in detail in some embodiments, reference can be made to the relevant descriptions of other embodiments.

[0040] It should be understood that in some embodiments of the present invention, the disclosed technical content can be realized in other ways. The above-described device embodiments are merely illustrative. For example, the division of the above units may be a kind of logical function division. In actual implementation, other division methods may be used. For example, some units or components may be combined or integrated into other systems, or some features may be ignored or not implemented. Meanwhile, the illustrated or discussed mutual couplings, direct couplings, or communication connections may be indirect couplings or communication connections through some interfaces, units, or modules, and may be electrical or other types.

[0041] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place or distributed across multiple units, and the objectives of the technology of this embodiment can be achieved by selecting some or all of them according to actual needs.

[0042] In addition, the performance units in each embodiment of the present invention may be integrated into a single processing unit, each unit may exist physically alone, or two or more units may be integrated into a single unit. The integrated units may be implemented in the form of hardware or software performance units.

[0043] The above-mentioned integrated unit may be realized in the form of a software performance unit, and may be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention may be essentially embodied in the form of a software product, or the contributions made to existing technology, or all or part of the technical solution may be embodied in the form of a software product, and the software product may be stored in a storage medium, which includes instructions that cause a computer device (such as a personal computer, a server, or a network device) to perform all or part of the steps of the above-mentioned methods described in each embodiment of the present invention. The above-mentioned storage medium may include media capable of storing each code, such as a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk, or an optical disk.

[0044] The above description is only a preferred embodiment of the present invention, and a person skilled in the art can make some improvements and modifications without departing from the principle of the present invention, and all these improvements and modifications should be considered within the protection scope of the present invention.

Claims

1. The method includes obtaining motor rotor angular position data; comparing the motor rotor angular position data with a motor rotor angular position required by a user, and inputting the difference into a motor rotor angular position control module; obtaining a second-order time derivative of the motor rotor angular position data to generate motor rotor angular acceleration data; and simultaneously inputting the motor rotor angular acceleration data and the output of the motor rotor angular position control module into an incremental inverse dynamics control module, and the expression of the incremental inverse dynamics control module is as follows: In the formula, Δi ｑ is the output current increment of the incremental inverse dynamics control module, and i ｑ is the output current of the incremental inverse dynamics control module, and i ｑ０ is the sampled value before the current output of the incremental inverse dynamics control module, J is the moment of inertia, p is the number of motor poles, and ψ ｍ is the permanent magnet magnetic flux, L ｑ is the q-axis inductance, L ｄ is the d-axis inductance, i ｄ is the d-axis current of the AC servo motor current control module, v θ is the virtual control variable in inverse dynamics control, is the second-order time derivative of the motor rotor rotation angle at the sampling point, and is the output of the incremental inverse dynamics control module input to the motor current control module.

1. A nonlinear adaptive AC servo motor angular position control method comprising:

2. The motor rotor angular position data is obtained from a motor rotor rotation angle encoder.

2. The method of claim 1 .

3. A computer-readable non-volatile storage medium having recorded thereon a program for causing a computer to execute the method described in claim 1 or claim 2.

4. a processor and a memory readable by the processor; The memory stores a program for causing the processor to execute the method according to claim 1 or 2. An electronic device characterized by:

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