基于线性差动变压传感器的高精度微位移测量系统

Design of High-precision Micrometric Displacement-measuring System Based on Linear Differential Transformer

针对现有微位移测量系统的不足,设计了一种高精度微位移测量方案。设计完善了信号调理电路,以线性差动变压传感器作为位移敏感元件,提出一种新的线性差动变压传感器正弦激励信号产生方法和多重反馈有源带通滤波器基波信号抽取电路。同时,为整个系统设计了完善的供电系统,采用TOP224构成反激式变换电路,再通过线性电源变换器转换至相应电压。微动测量架的校验结果表明,系统精度达到了1μm。

Considering shortcomings of existing micrometric measurement systems, a high-precision micromet- ric measurement scheme was designed and the signal processing circuit was perfected. Through having linear differential transformer displacement sensor （LVDT） taken as sensitive element for the displacement measure- ment, a new LVDT sine excitation signal generating method and a multiple feedback active band-pass filter fundamental signal extraction circuit were proposed; meanwhile, a perfect power supply for the whole system was designed which adopts TOP224 to form the flyback converter circuit and then converts it to the correspond- ing voltage. Verifying it on a mierometric displacement measurement bench shows that this system＇ s accuracy can reach 1μm.