准互易光学电压互感器数字闭环信号处理方法

介绍了一种用于准互易光学电压互感器的数字闭环信号处理方法.根据互感器光路输出信号的特点,采用基于方波调制解调的数字相关检测技术,提高了系统的响应灵敏度.在此基础上,引入阶梯波反馈技术,通过相位调制器在两束相干偏振光间引入一个与晶体Pockels相移大小相等、方向相反的反馈相移,实现闭环检测,扩大了动态范围,且不依赖于传...

Digital Closed- loop Signal Processing System for the Quasi- reciprocal Optical Voltage Sensor

A digital closed-loop detection scheme for the quasi-reciprocal optical voltage sensor(OVS) is proposed and demonstrated in this paper.According to the characteristic of the interferometic signal,a digital correlation detection scheme based on square wave modulation and demodulation is applied to improve the sensitivity of OVS.By introducing a digital ramp feedback technology,a feedback phase shift between the two polarization beams is created to offset voltage induced Pockels phase according to the optical phase modulator.In this way,the closed-loop scheme is realized,which improves the dynamic range and independent on the half-wave of the sensing crystal.The experiments are implemented on the OVS with the proposed digital closed-loop detection scheme.The experiment results show that the DC voltage from 0 to 3000 V and 50 Hz AC voltage from 0 to 4000 V are measured with good linearity.The proposed OVS achieves accuracy within ± 1 % with the measured DC voltage above 800 V.And measurement accuracy is less than ± 0.44 % and ± 0.2 % with the AC voltage above 25V and 690 V,respectively.The results verify the feasibility of the closed-loop scheme.