一种新型光纤电压互感器的设计

介绍了一种新型110 kV光纤电压互感器的基本原理和初步设计方案.该电压互感器基于石英晶体的逆压电效应,电压通过金属电极加在石英晶体的两端,电场方向和石英晶体纵向传感轴平行.利用2段椭圆芯双模光纤,第1段作为传感光纤缠绕在石英晶体上以感知交变电场导致的压电形变,第2段作为接收光纤跟踪Lp 01模式和LPeven 11模式之间相位差的变化.该方法源于白光干涉技术,包括2个级联的干涉仪,分别为传感干涉仪和接收干涉仪.采用780 nm,5 mW低相干多模激光二极管作为光源.讨论了互感器的参数设计,包括机械设计、双模光纤参数的研究以及传感光纤匝数的估算.最后介绍了互感器的工作条件和性能指标要求.

New Design of Fiber-optic Potential Transformer

The primary theory and design of a fiber-optic potential transformer for 110 kV transmission lines is investigated. The transformer is based on the converse piezoelectric effect of quartz. High AC voltage is applied to the quartzes by metal electrodes and the electric field is parallel to the sensitive axis of quartzes. There are two elliptical-core dual-mode fibers. The piezoelectric deformation of the cyllnder-shaped transducer crystal induced by an applied AC voltage is sensed by the first dual-mode fiber, which acts as a sensor fiber. The second dual-mode fiber acts as a receiver fiber to track the modulation of the differential phase of the LP01 mode and LP11^even mode of the sensor fiber. This method comes from the technology of white light interference which includes two interferometers in tandem, the unbalanced sensor and the receiver interferometers, respectively. The source is a 780 nm low-coherence multimode laser diode with 5 mW. And the design of the parameters of transformer is discussed, including the mechanical and optic-fiber designs as well as the estimation of loops of sensor fiber. Finally, the operational conditions for the transformer and the requirements on performance are described.