Circular array Hall current sensors have been widely used in the field of DC high current due to their low power consumption, high sensitivity and mechanical applicability. However, in the installation process, due to the existence of conductor eccentricity error, the current measurement accuracy of the array sensor is affected. In order to solve this problem, the paper analyzes the numerical integration algorithm and conductor position estimation algorithm, points out the shortcomings of the two algorithms, and proposes the design of magnetic field compensation algorithm on the basis of these two algorithms. Using MATLAB simulation and current sensor test platform, the magnetic field compensation algorithm to eliminate the eccentricity error is verified. By detecting the output voltage change of each Hall element after conductor deviation, the magnetic field component coefficient of each Hall element is automatically adjusted by feedback. Finally, the experimental results show that the algorithm can control the measurement error within 0.6%, and greatly improve the measurement accuracy of the sensor.