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所属单位：机电学院
发表刊物：Yi Qi Yi Biao Xue Bao
摘要：Piezoelectric actuator has been widely adopted in the field of high-precision positioning applications. However, its inherent hysteresis nonlinearity seriously deteriorates the positioning accuracy of PEAs. In order to accurately describe the hysteresis characteristic of PEAs, a support vector machine (SVM) hysteresis model is proposed in this paper based on nonlinear autoregressive-moving-average with exogenous inputs (NARMAX). To establish the SVM hysteresis model, first of all, it is necessary to convert the input output relationship of the PEA from a multivalued mapping problem into single-valued one. In this paper, the effects of different input variable single-valued mapping methods on the accuracy and generalization ability of the SVM hysteresis model are compared, a single-valued mapping method based on NARMAX is proposed, and a globally higher accuracy SVM hysteresis model for PEAs is established. By reducing the interval of the input signal frequency contained in the training set, the accuracy of the model on the test set is improved. The cross verification method is adopted to determine the parameters of the SVM model, which improves the global accuracy and generalization ability of the hysteresis model. The results show that compared with traditional B-W model, the model proposed in this paper more accurately describes the rate-dependent hysteresis of piezoelectric actuators, the accuracy is improved by 8 times at 1 Hz, by 60 times at 50 Hz and more at higher frequency. Through displacement tracking experiment, it is proved that the feedforward plus feedback (FF+FB) control based on SVM hysteresis inverse model can effectively improve the tracking accuracy. Compared with PID feedback control, the tracking error can be reduced by 73.9% at most. © 2018, Science Press. All right reserved.
ISSN号：0254-3087
是否译文：否
发表时间：2018-09-01
合写作者：Yan, Xiuquan,李遥,杨晓龙,Kang, Shengzheng
通讯作者：吴洪涛