Identification Modeling And Model-Free Adaptive Control Of Traveling Wave Type Ultrasonic Motors

Ultrasonic motor is a new type of direct-drive micro motor with excellent characteristics such as low speed and high torque,no electromagnetic interference,fast response,and automatic latching in power failure,so it is widely used in automotive,robotics,precision instruments,aerospace and other fields.In this paper,we aim to improve the speed regulation method of ultrasonic motor,introduce model-free adaptive control strategy,and build a model-free adaptive speed control system of ultrasonic motor by using DSPF28335 as the core component of control.The research of this paper is as follows:First,after analyzing the operation principle of ultrasonic motor,three speed regulation methods of ultrasonic motor are induced,and the speed regulation method used in this paper is determined as frequency regulation.To address the problem that the ultrasonic motor speed control model is nonlinear and it is difficult to obtain its accurate model,the Hammerstein identification model of the ultrasonic motor is established based on the input and output data of the ultrasonic motor with the nonparametric identification method.Then,for the problem that the parameters of the model-free adaptive control algorithm are difficult to adjust,the equilibrium optimizer algorithm is introduced to find the optimization of the model-free adaptive control parameters.For the problems that the equilibrium optimizer algorithm is easy to be trapped in local optimum,low convergence accuracy and premature maturity,an improved equilibrium optimizer algorithm is proposed by using strategies such as adaptive generation probability,refractive backward learning and Cauchy variation.The improved equilibrium optimizer algorithm is compared and analyzed with the model-free adaptive control optimized by the traditional equilibrium optimizer algorithm and the traditional model-free adaptive control on Matlab/Simulink,and the superiority of the improved algorithm is verified.After that,a variable-domain fuzzy model-free adaptive control algorithm with online rectifiable control parameters is discussed.The design process of variable-domain fuzzy model-free adaptive controller is described,and the fuzzy domain and quantization factor are determined according to the system speed error and error change rate.After analyzing the influence of parameters on the control performance in model-free adaptive control,the fuzzy control rules are designed with the experience of parameter debugging.A function-based scaling factor is used to realize the fuzzy theoretical domain changing with the system operation state.By comparing and analyzing with the fuzzy model-free adaptive control algorithm and the traditional model-free adaptive control algorithm on Matlab/Simulink,it is verified that the proposed control algorithm can adjust the parameters adaptively according to the system operation state and improve the dynamic response speed and robustness of the system against disturbances.Finally,the ultrasonic motor control platform with DSPF28335 as the core component is established,and the specific design of the experimental platform,the building process and the basic configuration of hardware and software are introduced,and the above is verified for experimental testing and analysis.