“Design of Genetically Tuned Interval Type-2 Fuzzy PID controller for Load Frequency Control (LFC) in the Un- regulated Power System”

This paper presents an Genetically Tuned interval type-2 fuzzy PID controller (GTIT2FPIDC) for the solution Load Frequency Control (LFC) problem in a deregulated power system that operate under deregulation based on the bilateral policy scheme. The interval type-2 fuzzy PID controller (GT-IT2FPIDC) is expected to compensate for the sudden load change, as the most effective countermeasure. In order to overcome difficulty of accuracy constructing the rule base in the IT2FPIDC, the parameters of the proposed controller is tuned by Genetic Algorithm (GA). The aim is to reduce interval type-2 fuzzy system effort, find a better fuzzy system control and take large parametric uncertainties into account. The proposed GA based IT2FPIDC controller is tested on a three-area deregulated power system. Analysis reveals that the proposed control strategy improves significantly the dynamical performances of system such as settling time and overshoot against parametric uncertainties for a wide range of area load demands and disturbances in either of the areas even in the presence of system nonlinearities. This newly developed strategy leads to a flexible controller with a simple structure that is easy to implement and therefore it can be useful for the real world power system. The proposed method is tested on a three-area power system with different contracted scenarios under various operating conditions. The results of the proposed controller are compared with the classical fuzzy PID type controller (CFPIDC).