研究了具有不同离散化台阶的正弦电压对压电陶瓷驱动器蠕变大小以及蠕变起始时间的影响,采用新的数学模型分析了低频下压电陶瓷驱动器的蠕变特性.首先,对0.025 Hz/0V~ 60 V正弦电压输入信号进行了5种倍数关系的离散化,分析了蠕变与输入电压的关系以及蠕变与输入台阶电压压差的关系.然后,按照提出的数学模型,在符合文中所述两种准则前提下,对蠕变起始时间进行了预测.实验结果表明,上升段蠕变变化范围最大出现在台阶电压等于47.7V时,而下降段蠕变变化范围最大出现在台阶电压等于12.3 V;相比于20个台阶,320个台阶对应的上升段最大蠕变增长量下降了899.5%,而在下降段最大蠕变的这一比值增大到了936.9%.使用所提公式对蠕变起始时间进行预测,得到当台阶电压为12.3 V时,20、40、80、160、320个台阶的蠕变起始时间分别在0.959、0.911、0.813、0.664和0.016 ms以后.蠕变与输入电压以及蠕变与输入台阶电压差值都是迟滞关系,并且台阶蠕变随着台阶数量的增加而减小.不同离散化的电压信号改变了蠕变的起始时间,台阶电压数量越多,蠕变起始时间越早.
The influence of sine voltages with different discretized stairs on the size and initial time of the creep for a stack PZT was investigated.A new model was presented to investigate the creep characteristics of the stack PZT in a low frequency.Firstly,a 0.025 Hz/0 V-60 V sine wave was discretized with five multiple relations.The relations between the creep and the stair voltage or the creep and the difference of stairs were also analyzed.Then,the initial time of the creep was predicted by the proposed model.Experimental results indicate that the biggest creep range in the rising period appears on the stair voltage of 47.7 V,and that in the decline period appears on the stair voltage of 12.3 V.As compared to 20 stairs,320 stairs correspond to the period of maximum creep growth in the rising falls by 899.5%,and that in the declining period is up to 936.9%.Using the proposed formula to predict creep initial time,the creep initial time of 20,40,80,160 and 320 stairs is 0.959,0.911,0.813,0.664,and 0.016 ms later respectively when the stair voltages is 12.3 V.Moreover,the differences between the creep and the input voltage and the creep and the input voltage are hysteresis,and the stair creep decreases with increasing the number of stairs.The voltage signal with different discretizations has changed the initila time of creep,and the more the stair voltage,the sooner the initial time of creep.