EE4504 Nonlinear Control:

 
Linear versus nonlinear systems. Describing function analysis: Fundamentals, common nonlinearities (saturation, dead-zone, on-off non-linearity, backlash, hysteresis) and their describing functions. Describing function analysis of nonlinear systems. Reliability of describing method analysis. Compensation and design of nonlinear system using describing function method. Phase plane analysis: Phase portraits, Singular points characterization. Analysis of non-linear systems using phase plane technique, Existence of limit cycles. Linearization: Exact linearization, input-state linearization, input-output linearization. Concept of stability, Stability in the sense of Lyapunov and absolute stability. Zero-input and BIBO stability. Second (or direct) method of Lyapunov stability theory for continuous and discrete time systems. Popov's stability criterion, generalized circle criterion, Kalman-Yakubovich-Popov Lemma. Disturbance issues in nonlinear control, non-linear control system design problem. Concepts of sliding mode control.