SoC FPGA-based field oriented control of BLDC motor using low resolution Hall sensor

Abstract

This paper presents an algorithm to generate a smooth rotor angle from Hall signals. Hall sensors are widely used in BLDC motor applications to provide rotor information for phase commutation, but the low angle resolution provided results in torque ripple and reduced efficiency. While the raw angle cannot be used directly, the rotor angle generated with the algorithm can be used in vector control to meet speed and torque demand on the drive with optimum power. The proposed algorithm has been designed to avoid multiplication and division operations for optimal use of FPGA resources to balance economical constraints with computational performance. It has been implemented in the Microsemi SmartFusion <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> 2 SoC FPGA.