Computer Modeling of Fiber Optic Current Sensor

Abstract

Despite all the advantages of using the fiber optic current sensors in high-voltage power networks, this technology has the significant weaknesses. They are the instability of the sensor readings and insufficient measurement accuracy. We observed parasitic response to the set of the entire factors in the real prototype of the fiber optic current sensor. Development of the current sensor computer model allowed us to analyze the influence of each factor on the measurement result individually and in complex without reconstructing the optical scheme every time. We used LabVIEW programming environment and Jones matrices formalism to develop the model of the sensor. We tested an algorithm that uses additional sinusoidal modulation and harmonic ratio analysis. The real-time model generated the raw photodetector signal that arises at the output of the sensor optical scheme when magnetic field is exposed to the sensing element, as well as demodulated signal of the current sensor. We have studied the effect of polarization mismatches at the fiber joints, the imperfections of the quarter-wave plate and the reflector at the measurements accuracy. Our model makes it easy to reconfigure the optical scheme of the current sensor to explore implementations of different configurations.