Research On Piezoelectric Ceramic Driver Power Supply For Piezoelectric Actuators

With the continuous development of science and technology,piezoelectric actuators have been widely used in various fields such as semiconductor manufacturing,aerospace,optical communications,and biomedical engineering due to their advantages of large stroke,fast response,and high precision.The piezoelectric ceramic driving power supply is a key factor that determines the motion speed and positioning accuracy of the piezoelectric actuator.Currently,in order to increase the stroke and output force,multiple piezoelectric stacks are used in piezoelectric actuators,but this brings problems such as slow step response,poor stability,and single channel number.In order to address these issues,the purpose of this research is to design a piezoelectric ceramic driving power supply specifically for piezoelectric actuators to achieve fast movement and precise positioning.Firstly,the characteristic parameters of piezoelectric ceramics are introduced,and the structure and performance of piezoelectric stacks are analyzed.A special measurement device is designed for analyzing the piezoelectric stacks,and the dynamic characteristics of the piezoelectric stacks are obtained.In addition,the overall structure and working principle of the piezoelectric linear motor are analyzed.Based on the dynamic output characteristics of the piezoelectric stacks and the working mechanism of the piezoelectric linear motor,the proposed technical specifications for the piezoelectric ceramic driving power supply are presented.Secondly,according to the requirements of the piezoelectric linear motor drive,the overall scheme design of the piezoelectric ceramic driving power supply was proposed.To address the issues of slow step response and single channel of the piezoelectric ceramic driving power supply,a composite two-stage linear amplification circuit composed of OPA2277UK and PA79DK was proposed.A low-voltage low-offset operational amplifier was selected as the front stage,and a high-voltage operational amplifier was selected as the back stage,and a composite amplification negative feedback connection method was adopted.In addition,the operational amplifier selection,linear amplification circuit,and driving power supply gain settings were analyzed.To address the issue of poor stability of the piezoelectric ceramic driving power supply,the frequency characteristics of the piezoelectric ceramic equivalent capacitor on the circuit were analyzed.In-depth research found that the circuit would have a new f_p pole after the drive power supply was connected to the capacitive load,causing circuit self-excited oscillation.Isolation resistors,feedback capacitors,and symmetric phase compensation schemes were used to correct the closure rate of the Aol curve and 1/βcurve,thereby improving system stability and performance.In order to address the safety issues of the piezoelectric ceramic driving power supply during operation,a 1W high-precision current limiting resistor and input/output protection diode were added to prevent excessive output current,reverse input of differential voltage,and charge reversal input of piezoelectric stacks under positive piezoelectric effect.Multisim circuit simulation software was used for simulation verification,and the results showed that the piezoelectric ceramic driving power supply has high dynamic and high stability.The PCB layout of the multi-channel piezoelectric ceramic driving power supply was drawn using EDA design software Altium Designer,and a prototype was fabricated for testing.Finally,in order to verify whether the piezoelectric ceramic drive power supply has achieved the research objectives,an experimental system was built for testing the piezoelectric ceramic drive power supply and the motor operation platform.An experimental measurement method was designed,and basic performance tests of the drive power supply and motor operation tests were carried out.The experimental results showed that in the drive power supply experiment,the maximum error between actual data and fitting value was 0.45395V when the input voltage was 2.2V,the nonlinearity error was less than 0.5%,and the step response was T_up=40μs under no load and T_up<1ms under 1.6μF load.The maximum drift within two hours was less than or equal to 10m V.By changing the frequency,the output voltage control signal could be well obtained under both no load and load conditions.In the motor operation experiment,the developed prototype drive power supply was used to operate the piezoelectric linear motor,and the maximum operating speed was 0.08mm/s.The purpose of this research project is to design a dedicated piezoelectric ceramic driver for piezoelectric actuators.This involves the implementation of a composite two-stage linear amplification circuit,a phase compensation circuit,a capacitive load compensation circuit,as well as current limiting and protection circuits.The driver circuit has been successfully built and its feasibility has been verified through simulation analysis.A multi-channel piezoelectric ceramic driver prototype has been manufactured for physical experimentation and validation.The designed piezoelectric ceramic driver meets the operational requirements of piezoelectric linear motors and has significant implications for promoting research and applications in piezoelectric actuators.