Characteristics Test And Control Research On Piezoelectric Ceramics Driver

With the continuous application of Piezoelectric ceramic actuator(PZT) in the field of new technology, the requirement of precision is also greatly improved for Piezoelectric ceramic actuator. In this paper, Piezoelectric ceramic is taken as the research object, the model identification algorithm of piezoelectric ceramics is proposed to design more accurate and effective piezoelectric ceramics controller based on the data obtained by experiment.The detail research contents are as follows:Firstly, the virtual instrument system of the driving characteristics is built in Lab VIEW to obtain the curve of the excitation signal and the corresponding signal of piezoelectric ceramics. According to the curve, we can see that piezoelectric ceramic has tracking property. However, it also has nonlinear characteristics, such as hysteresis and creep characteristics. Then, the hysteresis and creep characteristics of the piezoelectric ceramics are identified. The linear model and nonlinear model are built, respectively. The linear ARX(Auto Regressivee Xogenous) model is simple, but the error is relatively large. The nonlinear PI(Prandtl-Ishlinskii) model is more complex and has higher accuracy. Because of the high accuracy of nonlinear modeling, the creep behavior of the piezoelectric ceramics is directly used to make a nonlinear model based on the creep operator. After that, the model built in this paper is simulated in MATLAB/Simulink. Comparing the corresponding signal collected from experiment platform and the error curve data, the order of the model is changed until the minimum error is got and the precise mathematics model is obtained. Finally, the effective control algorithms are designed accordingly based on the model built. Their advantages and disadvantages are compared, the periodical output feedback control is selected for ARX(Auto Regressivee Xogenous) model. The inversion controller is designed for the PI(Prandtl-Ishlinskii) model and the creep model based on creep operators. The control system simulation is carried out in MATLAB/Simulink. The controller designed is ran and the output results are compared and verified to ensure that whether the nonlinear compensation control is got. At the end of this paper, the work done is summarized, and expectation about future research of piezoelectric ceramics is also made.