Nonlinear Hammerstein model of ultrasonic motor for position control using differential evolution algorithm

• DOI: 10.1016/j.ultras.2018.12.012
• Publication Date: 2018-12-23T11:35:09Z
• Authors: Song Lu; Shi Jingzhuo
• Keywords: Nonlinear Dynamics; 0103 physical sciences; Computer Simulation; Ultrasonics; Equipment Design; Micro-Electrical-Mechanical Systems; 01 natural sciences; Algorithms

The model of ultrasonic motor (USM) is the foundation of the analysis and control of the motor. Ultrasonic motor maintains nonlinear and complicated in dynamics due to its special structure and unique operating, which makes it difficult to establish a good model with traditional modeling. Moreover, the model should be established in line with strong nonlinearities. The nonlinear Hammerstein model of USM is established in this paper, which can better characterize the nonlinear motor. To adapt the model to the need of position control of ultrasonic motor, driving frequency and rotor position are considered as the input and output variables of the Hammerstein model respectively. To improve the accuracy of model and the efficiency of modeling process, model identification combined with differential evolution algorithm is designed. The comparison of model calculation results with the experimental data shows the accuracy of the established model and the validity of the proposed modeling.