高压驱动下介电弹性体电容检测系统

System for Detecting Capacitance of Dielectric Elastomers Driven by High Voltage

介电弹性体通常需要在kV级电压下驱动,但由于高压的存在,其驱动过程中的电容难以测量。对此,文中设计了一种高压驱动下介电弹性体电容的检测系统。系统以STM32F4为开发平台,硬件部分包括信号发生电路、差分采集电路和信号调理电路,单片机将硬件电路采集到的电压信号经过电容转换算法求得电容值后,通过串口通信协议传输给上位机。上位机由QT软件设计,能够实时显示电容数据并进行保存。经过实验测试,检测系统采集到的电容值与介电弹性体实际电容值误差小于3%,且具有良好的稳定性,为介电弹性体驱感一体化提供了技术支持。

Dielectric elastomers usually need to be driven at a voltage of kilovolts,but due to the existence of high voltage,the capacitance during the driving process is difficult to measure.In this regard,a system for detecting the capacitance of dielectric elastomers under high-voltage driving was designed.The system used STM32F4 as the development platform,and the hardware part included signal generation circuit,differential acquisition circuit and signal conditioning circuit.The single-chip microcomputer obtained the capacitance value from the voltage signals collected by the hardware circuit through the capacitance conversion algorithm,and then the voltage signals were transmitted to the host computer through the serial port communication protocol.The upper computer was designed by QT software,which can display and save the capacitance data in real time.After experimental testing,the error between the capacitance value collected by the detection system and the actual capacitance value of the dielectric elastomer is less than 3%,and it has good stability,which provides important technical support for the integration of the dielectric elastomer drive and sense.