Research on nonlinear correction of giant magnetostrictive material optical current transformer

Abstract

Due to the inherent hysteresis and nonlinearity of giant magnetostrictive material (GMM), the measurement waveform of optical fiber current transformer based on GMM material was distorted, which seriously affects the instantaneous accuracy of measurement results. In this paper, a correction method to data signal was proposed based on the law of graphics. The nonlinearity characteristic of the experimental system was analyzed, the transfer model corresponding to the unknown measured current was derived, and the measurement results were corrected by the inverse model. The comparison with experimental results showed that, this correction method could effectively reduce the influence of the nonlinear and hysteresis characteristics of GMM on the measurement results, at same time it greatly improved the measurement accuracy of the GMM current transformer.