The compensation of long‐term temperature induced error in the all fiber current transformer through optimizing initial phase delay in λ/4 wave plate.

The long‐term temperature induced errors caused by fiber λ/4 wave plate and the Verdet constant of sensing fiber in the all fiber current transformer (FOCT) are theoretically analyzed. A temperature related response of fiber λ/4 wave plate is adopted to compensate for the change caused by temperature related Verdet constant through choosing appropriate initial phase retardation of the λ/4 wave plate. The experimental results show high temperature‐cycle accuracy in this kind of FOCT with relative error within 0.6%. [ABSTRACT FROM AUTHOR]