针对传统Bouc-Wen模型不能反映压电陶瓷作动器迟滞的非对称特性而导致其补偿控制精度难以提高的问题,提出了一种改进Bouc-Wen模型,通过修改形状控制参数使其能够模拟压电陶瓷作动器的非对称迟滞曲线.利用粒子群优化算法辨识了所需的模型参数,进一步研究了基于模型的前馈补偿控制、前馈加PI反馈补偿控制对于实现高精度位移输出的效果；在开环前馈补偿控制实验中,采用改进Bouc-Wen模型比传统Bouc-Wen模型的控制误差可降低约42％；在前馈加PI反馈补偿控制实验中,采用改进Bouc-Wen模型比传统Bouc-Wen模型的控制误差可降低约20％.研究结果表明:在相同的控制方式下,采用改进Bouc-Wen模型能够得到比传统Bouc-Wen模型更高的轨迹跟踪精度；与单纯采用基于模型的前馈补偿控制相比,采用基于模型的前馈加PI反馈补偿控制可显著提高压电陶瓷作动器的位移输出精度.%Aiming at the disadvantage of the conventional Bouc-Wen model in formulating the asymmetric hysteresis of piezoceramic actuators, a modified Bouc-Wen model was proposed so as to improve the accuracy of model-based compensation control of piezoceramic actuators. The modified Bouc-Wen model was introduced by ameliorating shape control parameters to simulate the asymmetric hysteresis curve of piezoceramic actuator. The parameters of the modified Bouc-Wen model were identified by particle swarm optimization algorithm. Feedforward compensation control as well as feedforward plus PI feedback control based on the proposed model were carried out to investigate its effectiveness on improving the displacement output accuracy. In comparison with control experiments by using the traditional Bouc-Wen model, the displacement output error by using the modified Bouc-Wen model could be reduced by approximately 42% in open-loop feedforward control and 20% in feedforward plus PI feedback control. The results indicate that, for the same control method, compensation control by using the modified Bouc-Wen model can achieve higher trajectory tracking accuracy. Furthermore, model-based feedforward plus PI feedback can achieve better control accuracy in comparing with only feedforward control.
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