Magnetic Ball Levitation System Control Using Sliding Mode Control and Fuzzy PD plus I Control: A Comparative Study

This paper presents a comparative study of three control approaches; fuzzy proportional and derivative control with increment (PD+I) controller of both Mamdani and Takagi-Sugeno (TS) inference system and sliding mode control (SMC). It presents the implementation of both intelligent and nonlinear control in a highly open loop unstable nonlinear system. Instead of fuzzy PID controller, PD+I controller is implemented for both the fuzzy controller for avoiding problem of integral windup. A robust SMC is designed without transforming into the canonical form. Important control problem i.e. tracking of ball position of magnetic ball levitation system (Maglev), which is very difficult to control, is done on the practical platform and the performances of all the controllers are compared. Simulation is performed to demonstrate the effectiveness of control strategies. Simulation result reveals that control schemes are working satisfactorily. Control effort and degree of tracking for all the controllers are analyzed and compared.