Design of Sliding Mode Control for a Brushless DC Motor

Brushless DC motors are used in a wide variety of industrial applications including robotics, medical machinery, automobiles, marine, aerospace and defense industries. In such applications, there are variations in environmental conditions which results into deviation of actual model from the nominal one. That is, there are significant modeling errors and external disturbances. So, a robust control technique is required which could mitigate these issues. Multiple control techniques have been proposed but none of them offer a complete and robust solution for speed control along with keeping other parameters such as phase currents and peak torque in bounds. This paper will be presenting a robust solution using a sliding mode controller paired with a hysteresis current controller. Furthermore, the proposed technique has the additional advantage that it does not need additional sensors for current measurement. To verify the authenticity of the results the simulation results of the sliding mode control and its comparison with conventional control techniques will also be presented.