Quasi-reciprocal optical closed-loop lithium niobate optical waveguide alternating electric field/voltage sensor

Abstract

The invention provides a quasi-reciprocal optical closed-loop lithium niobate optical waveguide alternating electric field / voltage sensor. The quasi-reciprocal optical closed-loop lithium niobate optical waveguide alternating electric field / voltage sensor comprises a light source, a circulator, a polarizer, a phase modulator, a polarization-maintaining time delay optical fiber, a measuring optical path, a compensating optical path, a photodiode, a signal processing and light source driving circuit and a signal outputting and control interface. A polarization-maintaining optical fiber polarization shaft between the polarizer and the phase modulator is subjected to 45-degree counter-shaft fusion welding, a lithium niobate straight waveguide sensing unit of the measuring optical path and a compensating optical fiber of the compensating optical path are subjected to 90-degree counter-shaft coupling. Two cross-polarization modes participating in interference are interchanged when passing through the optical paths back and forth for two times and have the same optical path length, and a quasi-reciprocal reflection-type optical path for optical fiber conduction and waveguide sensing is formed. The quasi-reciprocal optical closed-loop lithium niobate optical waveguide alternating electric field / voltage sensor utilizes Pockels electrooptical effect of a lithium niobate crystal to modulate optical phases, achieves electric field / voltage measurement, has high sensitivity and measurement accuracy, can effectively separate components of direct current and alternating current of measured voltage and decrease a optical path space and is easily produced in a large-scale mode.

Description

technical field [0001] The invention belongs to the technical field of optical sensing, in particular to a quasi-reciprocal digital closed-loop lithium niobate optical waveguide alternating electric field / voltage sensor. Background technique [0002] The power system is the lifeblood of the national economy. Electric field sensors and voltage sensors are one of the basic measurement devices for power metering and relay protection in the power system. Their accuracy and reliability are closely related to the safe, reliable and economical operation of the power system. With the increase of power production and power transmission system capacity, the operating voltage level of the power grid is getting higher and higher, and the requirements for digitization, intelligence and networking in monitoring, control and protection are constantly increasing. Traditional electromagnetic electric field sensors and voltage Due to its inherent defects, sensors can no longer meet the develo...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the existing problems of the existing optical electric field sensor and voltage sensor, such as complex optical path structure, large volume, difficulty in large-scale production, poor temperature stability, and inherent bias affected by temperature, etc., and improve the sensitivity and stability of voltage measurement, the invention provides A quasi-reciprocal digital closed-loop lithium niobate optical waveguide alternating electric field / voltage sensor

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