US-20260128696-A1 - NONLINEAR AND ADAPTIVE ALTERNATING-CURRENT SERVO ELECTRIC MOTOR ANGULAR POSITION CONTROL METHOD AND SYSTEM

Abstract

A nonlinear and adaptive alternating-current servo electric motor angular position control method and system includes: acquiring original electric motor rotor angular position data; inputting the original electric motor rotor angular position data into a rotor angular position control module; performing second-order time differentiation on the electric motor rotor position data, so as to generate electric motor rotor angular acceleration data; inputting the electric motor rotor angular acceleration data and an output from the rotor angular position control module into an incremental inverse dynamic control module at the same time; and inputting the output from the incremental inverse dynamic control module into an electric motor current control module.

Inventors

• Xiaochen ZHANG
• Qiping Chu
• Jianhao ZHANG

Assignees

• TIANJIN SAIXIANG TECHNOLOGY CO., LTD

Dates

Publication Date

20260507

Application Date

20220411

Priority Date

20211119

Claims (4)

1. 1 . A method for nonlinear adaptive control of angular position of an AC servo motor, comprising: obtaining angular position data of a rotor; comparing the angular position data of the rotor with a desired angular position of the rotor, a difference of which being inputted to a rotor angular position control processing circuit; taking a second-order time derivative of the angular position data of the rotor to generate angular acceleration data of the rotor; inputting both of the angular acceleration data of the rotor and an output of the rotor angular position control processing circuit to an incremental dynamic inversion control processing circuit; wherein the incremental dynamic inversion control processing circuit is expressed as: Δ ⁢ i q = ( i q - i q ⁢ 0 ) = J p [ ψ m - ( L q - L d ) ⁢ i d ] ⁢ ( v θ - d 2 ⁢ θ dt 2 ❘ 0 ) where q denotes an increment of output current of the incremental dynamic inversion control processing circuit, i q denotes an output current of the incremental dynamic inversion control processing circuit, i q0 denotes a preceding sample value of the output current of the incremental dynamic inversion control processing circuit, J denotes a rotational inertia, p denotes the number of magnetic poles of the motor, ψ m denotes a magnetic flux of permanent magnet, L q denotes a q-axis inductance, L d denotes a d-axis inductance, i d denotes a d-axis current, v θ denotes a virtual control variable in dynamic inversion control, and ? ? ? ? ? ❘ ? ? indicates text missing or illegible when filed denotes a second-order time derivative of the angle of rotation of the rotor at a sampling point; and inputting an output of the incremental dynamic inversion control processing circuit to a motor current control processing circuit.
2. 2 . The method of claim 1 , wherein the angular position data of the rotor is taken from a rotor rotating angle encoder.
3. 3 . A nonvolatile memory medium, comprising a program stored, wherein the program, when running, controls a device hosting the nonvolatile memory medium to perform the method according to claim 1 .
4. 4 . An electronic device, comprising a processor and a memory, a computer-readable instruction being stored in the memory, the processor being configured to run the computer-readable instruction, wherein the computer-readable instruction, when being executed, performs the method according to claim 1 .

Description

FIELD The present disclosure relates to motor control, and more particularly relates to a method and a system for nonlinear adaptive control of angular position of an AC servo motor. BACKGROUND With constant advancements in smart technology, smart devices have been increasingly infiltrated in people's daily life, work, and study, contributing improved life quality and enhanced learning and work efficiency. In the field of motor control, a motor system is essentially nonlinear, time-varying, and uncertain, so that a nonlinear adaptive control algorithm is required in designing of its control system. Currently, the traditional PID (Proportional, Integral, and Differential) control algorithm is generally adopted for the servo control system of all motors. However, the PID control algorithm is a linear system-oriented control algorithm, so that when the PID algorithm is used to control a nonlinear servo motor, a problem arises as to how to tune the proportional, integral, and differential parameters. Due to the nonlinearity, time-variation, and uncertainty of the motor system, it is essential to off-line or on-line identify the non-linear or linear motor and load models. The identified motor and load models are used for tuning the PID parameters instantly or by segments. The parameters of the traditional PID algorithm are constant throughout the control process, while in practical applications, the controlled system as a whole is unpredictable, so that invariant PID parameters cannot contribute a high-performance control effect to the system. Although a notable control effect can be achieved, model identification, particularly online model identification, also significantly increases system complexity; in addition, model identification cannot always guarantee correctness of the identified models or model parameters, so that an adaptive control system relying on this traditional PID algorithm can hardly be certified industrially. Other adaptive or smart control methods, such as fuzzy control, sliding mode control, neural network-based control, model reference adaptive control (MRAC), also have a problem of being unable to ensure algorithm stability or stable operation under any operating load. By far, no effective solution has been provided to the problems noted supra yet. SUMMARY Implementations of the disclosure provide a method and a system for nonlinear adaptive control of angular position of an AC servo motor to overcome the technical problems in conventional servo motor control technologies such as difficulties in identifying the motor model and the load model as well as tuning of time-varying parameters of the controller. In one aspect of the disclosure, there is provided a method for nonlinear adaptive control of angular position of an AC servo motor, comprising: obtaining angular position data of a rotor;comparing the angular position data of the rotor with a desired angular position of the rotor, a difference of which being inputted to a rotor angular position control processing circuit;taking a second-order time derivative of the angular position data of the rotor to generate angular acceleration data of the rotor;inputting both of the angular acceleration data of the rotor and an output of the rotor angular position control processing circuit to an incremental dynamic inversion control processing circuit; andinputting an output of the incremental dynamic inversion control processing circuit to a motor current control processing circuit. The angular position data of the rotor is taken from a rotor rotating angle encoder. The incremental dynamic inversion control processing circuit is expressed as: Δ⁢iq=(iq-iq⁢0)=Jp[ψm-(Lq-Ld)⁢id]⁢(vθ-d2⁢θdt2❘0)where Δiq denotes an increment of output current of the incremental dynamic inversion control processing circuit, iq denotes an output current of the incremental dynamic inversion control processing circuit, iq0 denotes a preceding sample value of the output current of the incremental dynamic inversion control processing circuit, J denotes a rotational inertia, p denotes the number of magnetic poles of the motor, ψm denotes a magnetic flux of permanent magnet, Lq denotes a q-axis inductance, Ld denotes a d-axis inductance, id denotes a d-axis current, vθ denotes virtual control variable in dynamic inversion control, and d?⁢θdt?❘0?indicates text missing or illegible when filed denotes a second-order time derivative of the angle of rotation of the rotor at the present sampling time. Furthermore, control of the AC servo module further comprises: a motor current control processing circuit. Another aspect of the disclosure further provides a nonvolatile memory medium, comprising a program stored, wherein the program, when running, controls a device hosting the nonvolatile memory medium to perform the method for nonlinear adaptive control of angular position of an AC servo motor. A further aspect of the disclosure also discloses an electronic device, comprising a proc