超声波电机非线性自适应位置控制

Nonlinear Adaptive Position Control of Ultrasonic Motor

超声波电机的运行过程具有明显的非线性和时变特性,不易获得良好的运动控制性能。针对这种非线性和时变特性,本文基于超声波电机非线性Hammerstein模型,给出一种非线性位置控制策略。该控制策略由两部分构成;一部分是超声波电机模型非线性部分的逆,用来抵消电机的主要非线性特性;另一部分为直接多步预测自适应控制策略,通过滚动优化实现对电机系统时变特性的在线补偿。实验结果表明了所提控制策略的有效性。

Ultrasonic motor presents obvious nonlinearity and time-varying characteristics in its operational process. These imperfect characteristics make it difficult to achieve precise control. On the basis of the non- linear Hammerstein model of ultrasonic motor, a novel nonlinear position control strategy was presented in this paper. The control strategy is composed of two parts. The inversion of the model＇s nonlinear part is set as one part of controller to counteract the nonlinearity of motor. For the remainder linear characteristics of mo- tor, the direct general predictive position control strategy was designed to compensate the time-varying characteristic of ultrasonic motor by rolling optimization. trol strategy. Experimental results show the effectiveness of this control strategy.