Optimal design of optical fiber current transformers under multi-objective parameter optimization

Aiming at the problem that the dynamic response and signal-to-noise ratio (SNR) of the optical fiber current transformer system are affected by the coupling of system parameters, this paper proposes a fiber optic current transformer (FOCT) optimization design method under multi-objective parameter optimization to achieve a comprehensive improvement in the performance of the transformer. Firstly, FOCT dynamic response analysis and SNR analysis are conducted to study the influence laws of system parameters on the step response index and SNR, and the optimized parameters are determined. Then, based on the multi-objective particle swarm optimization (MOPSO) algorithm, forward gain optimization is carried out under the dual targets of step response and overshoot, and system parameter optimization under the SNR target based on the PSO algorithm is conducted with the forward gain as the constraint to determine the parameter combination of the transformer system for synchronous optimization of step response and SNR. Finally, a FOCT is designed based on the combination of system parameters, and SNR tests and step response tests are carried out to compare and verify the FOCT performance before and after optimization. Experimental results demonstrate that after optimization, the FOCT's step response rise time is shorter than 50 μs, and the transformer's SNR can reach 21.5 dB under 10 A current. Furthermore, the FOCT meets the accuracy requirement of 0.2S class.