线性光耦HCNR201原理及其在轴承故障检测中的应用

因铁路货车轴承故障检测现场工况复杂,各种电磁干扰信号极易随被测信号进入测量系统.针对这个问题,设计了用高线性度模拟光耦HCNR201和运算放大器实现的电压隔离硬件电路.该电路中,线性光耦的前端用一个运算放大器构成一个负反馈放大器,用来检测模拟电压信号;线性光耦后端的运算放大器进行电流与电压之间的转换,最终输出电压信号,实现电压信号的1：1隔离传输.实验结果表明：该方法测量电压线性度好、精度高.

Principle of Linearity Optocouplers HCNR201 and Its Applications in Bearing Fault Detection

Because railway trucks bearing fault detection field conditions are extremely complicated,every electromagnetic interference signals can easily enter the measurement system along with the measured signal.To address this issue,the voltage isolation hardware circuit achieved by high linearity analog optocoupler HCNR201 and operational amplifier was designed.In the circuit,one operational amplifier is used as a negative feedback amplifier in front of the linear optocoupler,which is used to detect analog voltage signal;the operational amplifier at the end of linear optocoupler makes a conversion between the current and voltage,outputs finely voltage signal and achieves the 1：1 isolation transmission of voltage signal.The experimental results show that the measuring method can realize the good voltage linearity and high accuracy.