Three-phase integrated all-fiber current transformer

Abstract

The invention relates to a three-phase integrated all-fiber current transformer. The three-phase integrated all-fiber current transformer comprises a light source and an optical splitter connected with the light source, and further comprises a first phase modulator, a second phase modulator and a third phase modulator, wherein the first phase modulator, the second phase modulator and the third phase modulator are connected with the optical splitter simultaneously. The first phase modulator is connected with a first delay winding and a first sensitive element in sequence. The second phase modulator is connected with a second delay winding and a second sensitive element in sequence. The third phase modulator is connected with a third delay winding and a third sensitive element in sequence. The output end of the optical splitter on a return light path is connected with a photoelectric detector and a digital signal acquisition and processing circuit in sequence. The digital signal acquisition and processing circuit is in closed-loop feedback connection with the first phase modulator, the second phase modulator and the third phase modulator. By the adoption of the three-phase integrated all-fiber current transformer, measurement of three-phase currents can be completed simultaneously through one device, so that the number of applied phases of optical devices and circuit devices is greatly reduced, the cost is lowered, and the integration level of the whole set of equipment is improved.

Description

technical field [0001] The invention relates to the technical field of electric equipment, in particular to a three-phase integrated all-optical current transformer. Background technique [0002] The current transformer is an important device for relay protection and electric energy metering in the power system. It is used to measure the current in transmission and send the measured current to the measuring instrument and relay protection device. Its long-term stability, reliability, and security are closely related to the safe and stable operation of the power system. Traditional electromagnetic current transformers have been used for a long time in conventional power transmission and transformation, but they have disadvantages such as complex insulation, magnetic saturation, poor anti-electromagnetic interference performance, explosion, and secondary open-circuit danger. With the increase of the voltage level of my country's power grid, These problems are increasingly prom...

AI Technical Summary

Problems solved by technology

[0004] The present invention aims at the problems of high overall cost and low integration when the existing all-fiber-optic current transformer measures three-phase current, and provides a new type of three-phase integrated all-fiber-optic current transformer, which can simultaneously Complete the measurement of three-phase current, and greatly reduce the number of optical devices and circuit equipment used in each phase, reduce the cost, reduce the volume, and improve the integration and reliability of the whole set of equipment

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