Optical fiber power frequency electric field sensor

Abstract

The invention discloses an optical fiber power frequency electric field sensor. The sensor comprises an optical fiber electric field sensitive element and an insulating packaging housing. The electric field sensitive element comprises two fiber bragg gratings or a fiber F-P (Fabry-Perot) resonator which is formed by combining a fiber bragg grating and an optical fiber facing plating reflecting mirror. By coating a polymer resin on the surface of the optical fiber including the F-P resonator, the sensor has a sensing function of sensing transient variation of an outside power frequency electric field so as to generate vibration under the effect of the outside power frequency electric field. The sensor is connected with an optical interface of a laser vibration measuring instrument so that intensity, phase, frequency and other elements of the signal of the power frequency electric field can be detected. Compared with an electric field sensor based on electric effect and electro-optic effect on the current market, the sensor provided by the invention, which is a novel optical fiber power frequency electric field sensor, has the advantages of small volume, no metal part, no effect on the detected electric field, capability of being embedded or buried into insulating materials, particular suitability for all-optically and remotely monitoring the power frequency high voltage without power supply in real time for a long time in high voltage alternating current power transmission lines, transformer substations and other places.

Description

technical field [0001] The invention relates to a power frequency electric field sensor, in particular to an optical fiber power frequency electric field sensor. technical background [0002] In the power system, for a long time, the traditional electrical sensors based on thermocouple detection and diode detection principles have been mainly used to measure the power frequency electric field. The traditional electric field sensor is based on the time-domain average of the electric field signal and the measurement of the electric field energy, so it is not suitable for the measurement of the instantaneous change of the electric field, including the change of intensity, phase and frequency. [0003] On the other hand, in the traditional electric field measurement system, the probe and the measuring device are mostly connected through electrical lines. The measured electric field will produce electromagnetic induction phenomenon on these metal parts, resulting in the distorti...

AI Technical Summary

Problems solved by technology

However, due to the polarization characteristics of the crystal, the sensor probe needs to be connected to the light source with a polarization-maintaining optical fiber, and another transmission optical fiber is required to introduce the interference signal light into the measurement system, resulting in a complex system structure and high cost.

On the other hand, due to the large optical insertion loss of the crystal, it is difficult to realize the cascading to form a quasi-distributed sensor network

The sensitivity of this type of sensor is easily affected by temperature, and the structural adjustment of the probe must be carried out frequently to maintain the best working condition, and the operation is troublesome

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