Hybrid grating on-line temperature measurement type all-fiber current transformer and current detection method thereof

Abstract

The invention relates to a hybrid grating on-line temperature measurement type all-fiber current transformer, which comprises a current detection optical path and a temperature detection optical path, wherein the current detection optical path comprises a light source, a polarization-maintaining coupler, a phase modulator, a polarization beam combiner, a polarization-maintaining transmission optical fiber and a sensing head which are connected in sequence; the temperature detection optical path comprises the light source, the polarization-maintaining coupler, an optical circulator, a single-mode transmission optical fiber and the sensing head which are connected in sequence; the light source, the polarization-maintaining coupler and the sensing head are shared by the two optical paths; the two optical paths also comprise a common photoelectric conversion modulation and demodulation unit; and the photoelectric conversion modulation and demodulation unit is connected with the polarization-maintaining coupler and the optical circulator respectively. According to the hybrid grating on-line temperature measurement type all-fiber current transformer, the temperature of the sensing head can be measured in real time, and accurate and reliable correction can be performed on a measurement result of the current transformer.

Description

technical field [0001] The invention relates to a device for measuring the current in a conductor with an optical method and a detection method thereof, and belongs to the technical field of electric power application and optical fiber sensing. Background technique [0002] The all-fiber optic current transformer is a new generation of high-voltage and high-current measurement device, which uses optical fiber materials with natural and good insulation properties as sensing and transmission elements. The sensing unit has no electronic circuit and does not need a power supply. It is a passive current sensor. Compared with traditional current transformers, all-fiber current transformers have the following advantages: wide measurement frequency range; large dynamic range; good insulation performance; no risk of high voltage caused by open circuit; no iron core, no ferromagnetic resonance, magnetic saturation and large inductance The hysteresis caused by it; no oil, no explosion...

AI Technical Summary

Problems solved by technology

[0004] Although all-fiber current transformers have incomparable advantages over traditional current transformers, due to the temperature dependence of the 1 / 4 wave plate and the fiber optic Verdet constant in the optical path, the stability and measurement accuracy of current detection are affected. To a large extent, the application of fiber optic current transformers is limited

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