Multi-Channel Fiber Optic Current Simultaneous Measurement Scheme Based on Time Domain Superposition

This paper presents a novel design methodology for simultaneous multi-channel fiber optic current sensor. It integrates additional sensing channels into a standard reflective fiber-optic current sensor via optical couplers, sharing several key optical components and thereby significantly reducing system cost. By setting different lengths for the sensing channels, interference signals are superimposed at different positions in the time domain, allowing simultaneous demodulation of multi-channel current values. To validate the feasibility of this approach, a dual-channel fiber-optic current sensor is designed and experimentally verified. The current sensitivities of the two channels are 0.01663 mV/A and 0.03340 mV/A, respectively. Their crosstalk standard deviations are 0.00471 mV and 0.00033 mV, which are negligible. The technology is characterized by its straightforward design, low expenditure, and extensive potential for application.