Current measurement method based on integral reconstruction of magnetic rotation angle

Abstract

In view of the nonlinear limitation of the sine function on the magnetic rotation angle in the optical current sensor based on the light intensity detection mode, this paper proposes a current measurement method based on the integral reconstruction of the magnetic rotation angle, thus avoiding the large current measurement error caused by the approximate linear measurement of the magnetic rotation angle. In this method, the cosine term in the derivative of the sine signal containing the magnetic rotation angle is eliminated by the constant deformation of the trigonometric function, and then the magnetic rotation angle is reconstructed by integration. The experimental results show that within the current range of 0.20 Arms to 2.40 Arms, the measurement error of the current value of the integral reconstruction method is less than 1.30%, the measurement error is less than the approximate linear measurement method, and there is a good linear relationship between the magnetic rotation angle and the current, with a linearity of 99.987%.