Design and applicability analysis of independent double acquisition circuit of all-fiber optical current transformer

Abstract The advantages of the all-fiber optical current transformer include but are not limited to being small in size, having no magnetic saturation, exhibiting high measurement accuracy, and boasting strong electromagnetic interference resistance. However, the high cost of the all-fiber optical transformer limits its promotion and application in engineering. This paper proposes a design scheme of an independent double acquisition loop for the all-fiber optical current transformer based on the single optical path. Firstly, based on the closed-loop control mode and open-loop control mode, the two- channel sampling signal demand for relay protection, and the independent dual-acquisition loop design scheme of the all-fiber optical current transformer are proposed. Secondly, the reliability and economic feasibility of the scheme are demonstrated by an analysis of system failure and cost. The results show that the scheme can actualize the acquisition function of two independent all-fiber optical current transformer products on a single all-fiber current transformer in an integrated manner, which greatly reduces the cost of the all-fiber optical current transformer in engineering applications.