Integral Sliding Mode Control with Improved Reaching Law for Brushless DC Motor Speed Control

The design of speed control under various operation such as constant load situations, variable load situations and variable regulated speed situations of brushless DC motors is an important requirement. In brushless DC motors applications, there are modeling errors and external disturbance due to environmental conditions between the actual model and the nominal one. Besides these, due to the nonlinearity of the brushless DC motor driver's properties, traditional linear control methods fall short of their expectations in terms of efficiency. Therefore, a robust control method is necessary to overcome these issues. Sliding mode control is a robust nonlinear control technique against external disturbances and parameter uncertainties. This article proposes a sliding mode controller that uses integral sliding surface and has an improved reaching law in order to enhance the dynamic performance of management of the speed in brushless DC motors. The efficiency of the proposed controller under different test scenarios is evaluated and compared with other existing methods such as traditional SMC. The simulation results show that the proposed controller is superior to other methods and improves its dynamic performance.