Speed Control of a DC Motor by Recurrent Fuzzy Logic Control Technique

Abstract

In the present paper, we deal with controlling of the angular speed of a direct current (DC) motor under some nonlinear loads constant, signal and step, performing with closed loop control system, FLC, Recurrent FLC (RFLC) and Enhanced Recurrent FLC (ERFLC) Techniques in MATLAB / SIMULINK FUNCTIONS via Gradient Descent Algorithm. We obtain transfer function satisfied by DC motor. Drawback of the literature Fuzzy Logic Control membership functions is not to regulate the voltage values directly in dynamic systems and so the performance of the microcontroller is too low. That is the reason why we use some MATLAB FUNCTIONS with recurrent algorithms. RFLC Technique appears to have an angular speed stabilizer feature on the DC motor after the first two seconds with much less oscillation under the entire load change, but FLC values are discrete. In the ERFLC Technique, the angular speed of a DC motor under nonlinear loads is achieved by reaching the reference angular speed value with much less oscillation when the total load changes completely and clearer results are obtained. Thus, RFLC and ERFLC Techniques can be used for precise positioning system, global trajectory planning system of an electrical autonomous vehicles. In decision making system of an electrical autonomous vehicles, RFLC and ERFLC can be used in the anti-lock braking system to downhill speed control in level three and as an electronic stability control in the level four with foggy airs such that the visibility is extremely low and provide safe driving on slippery and icy surfaces.