新型光电式电压互感器研究

Study on a New Type Optic-electric Transformer

本文提出一种应用于500KV的光电式电压互感器。该互感器基于石英晶体的逆压电效应。高压经圆筒电容器分压后加到圆柱状的石英晶体上,晶体的压电形变被缠绕在晶体圆柱表面上的椭圆芯双模光纤传感,由低相干干涉仪对光纤中传播的两个空间模(LP01模和偶数LP11模)的微分光波相位的调制进行检测。该互感器除电容分压、石英晶体外,是一个全光纤的解决方案,没有准直仪、偏振片和波片等块状光学元件;进而降低了成本、提高了精度、便于规模化生产。本文给出了电压互感器的系统结构及绝缘设计,研究了互感器的性能,为高压电压互感器的应用提供了理论依据。

This paper presented an optic - electronic voltage transformer insulated by SF6, which is applied in 500KV （line voltage） power system. The voltage sensor is based on converse piezoelectric effect in a quartz crystal. High voltage is exerted on the quartz crystal after being divided by cylinder capacitor divider, piezoelectric deformation is sensed by elliptical-core dual-mode fiber around the surface of cylindrical crystal, the differential phase shift of light wave is recovered by means of two spatial modes （LP01 mode and even LP11 mode） transmitted in the optical fiber and interrogated by low-coherence interferometer. Except for capacitor divider and quartz crystal, it is a whole optical fiber scheme, no separated optical devices, such as collimators, polarizer and wave plates; Thus the cost of sensor is reduced, accuracy is advanced, and it is convenient for production in scale. Finally, the paper offered a design scheme for the voltage transformers＇ system and insulator, studied the performance of voltage transformer and provided a theory gist for the application of high voltage transformer.