Temperature Drift Compensation of Eddy Current Sensor under High Temperature Environment

Abstract

Eddy current sensor is an sensor based on eddy current effect. In practical engineering applications, the ambient temperature of eddy current sensor may be up to 135 ℃. The temperature drift of eddy current sensor magnifies the error of displacement detection. In this paper, the main factors that cause temperature drift are analyzed in detail, and the results show that the compensation based on single parameter can not meet the demand of high-precision measurement. For this reason, this paper proposes an external compensation method which applies mathematical fitting to realize compensation for temperature drift. The experimental results show that the measurement accuracy of the external compensation method reaches 0.25% in the working temperature range, which greatly improves the measurement accuracy of eddy current sensor under high temperature.