Research On Displacement Control Of Piezoelectricity Sensing Actuator Based On PID Theory

Piezoelectric sensor actuator is a nanoscale electromechanical integration system integrating piezoelectric drive amplifier,piezoelectric ceramic driver and sensor.It has infinite development potential in micro-nanomanufacturing and ultra-precision machining.In this paper,based on the existing piezoelectric sensor actuators in the laboratory,the system modeling,controller design and simulation verification are carried out,and a complete piezoelectric sensor actuator model and controller design scheme are obtained.A comprehensive mathematical model describing the piezoelectric sensor actuator system is established from the aspects of electrical characteristics,hysteresis effect,piezoelectric effect and mechanical body.Software was used to analyze the structure in time domain and frequency domain,explore the influence of system parameters on the response characteristics of the system,and analyze the causes of hysteresis.The system parameter identification and linear control scheme formulation and simulation are carried out.The hysteresis model modeling mechanism was clarified,and the model modeling analysis,model parameter simulation and algorithm preparation were carried out.According to the relationship between the measured input voltage and the output displacement,the least two norm method was used to solve the model parameters and simulate analysis,and the output displacement accuracy of the model was considered.The linear part is added to the static inverse model to optimize the modeling scheme.The modeling accuracy of the final Prandtl-Ishlinskii dynamic hysteresis model is ideal,the modeling average error is less than 0.053?m in the measured frequency interval,and the modeling relative error is 0.29%.The feedforward control system of hysteresis inverse model of piezoelectric sensor actuator is modeled and analyzed and the model parameters are solved.The output displacement accuracy of piezoelectric sensor actuator under the control of feedforward inverse model control system is considered.The control system scheme is optimized by adding a linear part on the basis of static inverse model.Finally,under the feedforward control system of the Prandtl-Ishlinskii dynamic hysteresis inverse model,the average error between the output displacement of the piezoelectric sensor actuator and the ideal output displacement is less than 0.464?m within the measured frequency range,and the relative error is 2.58%,and the control system needs to be further optimized.The PID feedback is combined with feedforward control based on hysteretic inverse model,and the control system is simulated by software.The output displacement curve obtained by experiment is in good agreement with the ideal one.The average error is less than0.133?mwithin the measured frequency range,the relative error is 0.74%,less than 1%,and the feasibility of the control scheme is verified.The fuzzy PID controller is designed and simulated with the help of software.The results show that the adjustment time of the fuzzy PID model is 0.09 s after the interference.The overshoot is 2.03% and good anti-interference effect is obtained.In this paper,the control scheme designed for piezoelectric sensor actuator system combining PID feedback with hysteresis inverse model feedforward has been verified by simulation to be effective and can be widely used in related fields where the linearity of piezoelectric actuators is high.