Analysis of robust interval type-2 fuzzy PID controller for AGC in a restructured power system

Abstract

The ever increasing demand of power has led to massive restructuring in power utilities throughout the globe which necessitates greater control in power management owing to uncertainty in load distribution. In the current work, we demonstrate the applicability of interval type-2 fuzzy logic controller (IT2FLC) four area automatic generation control (AGC) under a deregulated environment in mitigating and at the same time controlling the load uncertainties. The bilateral contracts of distribution companies (DISCO) w.r.t. generation companies (GENCO) is also simulated using distribution company participation matrix (DPM). Through literature survey it is found that, the current approach is based on type-1 fuzzy logic systems (T1FLS) which have crisp grade membership function (MF). In the current work, we have employed type-2 fuzzy logic system (T2FLS) which in itself consists of a fuzzy grade of MF. Genetic algorithm (GA) is employed to determine the optimum gain values of the proposed controller. In addition, the scaling factors (SF) and the footprint of uncertainty (FOU) of MF of interval type-2 fuzzy PID (IT2FPID) controller is also determined using the GA. The results of the simulation for multiarea deregulated power system employing the proposed GA based IT2FPID controller showed superior performance in comparison to optimally tuned conventional PID controller and type-1 fuzzy PID (T1FPID) controller under deregulated environment.