Sensorless control of BLDC motors based on Luenberger observer

This article introduces a discretized, low-order Luenberger observer designed for sensorless of the Brushless Direct Current Motors (BLDC). A vector control model for the BLDC is established. The reduced-order Luenberger observer estimates the EMF of the motor, while a PLL outputs the electrical angle and real-time speed of the motor. To validate the accuracy of the proposed sensorless algorithm, experiments were conducted in a MATLAB virtual environment and on an STM32G431CBT6 motor control platform. The observed electrical angle and rew of the motor converge with the actual motor position and speed output to achieve smooth acceleration control of the motor.