Chaos driven instability control using interval type-2 fuzzy logic controller for better performance

Engineering systems are governed by set of differential equations and work under various uncertainties of parameters. Type-1 fuzzy logic controller are widely used in engineering systems for expert control of system using logic and mathematics together. This paper proposes the first-ever use of Interval Type-2 fuzzy logic controller design to control chaos and associated instability in a nonlinear dynamical power system. Interval Type-2 fuzzy designs have an edge over type-1 fuzzy sets and interval type-2 fuzzy logic controller is well suited for the uncertainty present in weak and chaos sensitive systems. Uncertainty in parameters affects differential equation very badly for such systems. Uncertainty in engineering applications needs an extra layer of handling system control mathematically and logically. Comparison of Type-1 and Type-2 fuzzy logic controller based on time domain waveform, phase plane trajectory and integral square error, clearly proves the efficacy of Type-2 fuzzy logic controller in controlling dynamic behavior of a nonlinear dynamical system as demonstrated through results discussed in the paper. This paper discusses control of chaos driven voltage instability issue in the case of nonlinear dynamical power system, as an application.