Improving the Accuracy of Multipole Magnetic Encoder by Three-Phase Hall

Abstract

Magnetic encoders have widespread applications in various fields such as aerospace, automotive, robot joint control and machine tool turntables. For instance, obtaining accurate rotation angles of motors is crucial for servo motor control. Herein, we propose an angle-solving algorithm based on a dual-multipair pole magnetic encoder. First, we analyze the nonlinearity issue caused by installation error of the Hall signal and devise a self-adjustment algorithm for the analog signal. Second, we improve the high speed and robustness of the encoder in identifying eigenvalue intervals while solving for angles. Finally, through the big data analysis, the calibration compensation of curve fitting error was performed, and experiments were conducted to verify the effectiveness of the real-time angle-solving algorithm in a high-precision encoder.