Fiber fusion splicing error analysis of all-fiber optic current sensor with different demodulation schemes

Abstract

Measurement accuracy is essential for the all-fiber optic current sensor. Angle errors of axis alignment in the fusion processing affect the measurement accuracy with different modulation and demodulation methods. The relationship between observed and theoretical values has been analyzed with sinusoidal modulation and square modulation, respectively. The error and the error tolerance are computed with different demodulations based on the application of measurement and protection. The four demodulations are ordered based on the complexity and the error tolerance requirement. The open-loop demodulation scheme of the all-fiber optic current sensor can be applied for the protection application because it can be easily achieved. For the measurement application, the closed-loop feedback demodulation is recommended when the current is to be measured significantly; Otherwise, the harmonic division demodulation could meet the requirements of the system.

Keywords

• All-fiber optic current sensor
• Error analysis
• Sinusoidal modulation
• Square wave modulation