Performance Improvement of BLDC Motor Speed Control Using Sliding Mode Control and Observer

This work propose the sliding mode controller (SMC)-based field oriented control (FOC) for brushless direct current (BLDC) motor, and in later part investigated the speed and position estimation using higher order sliding mode observer (HOSMO), which may come as a solution for sensorless operation. The main idea of this work is to improve the dynamic response and reduce torque ripples in the BLDC motor with the proposed techniques. Speed tracking performance has been analyzed with different statistical performance and torque ripples with percentage variation with respect to the applied external torque. Further, rotor position and speed estimation using HOSMO is validated against real-time measured values and checked for percentage error. To validate the results of proposed approach, the SMC with HOSMO is implemented on a STM32Nucleo-144 development board and its performance is analyzed by hardware-in-the-loop co-simulations for reference tracking. Results shows that the designed SMC is a promising candidate for the BLDC motor control, with characteristics of improved speed tracking response for a wide speed range with minimum values for error performance indices and torque ripples are reduced by 5.84%.