GWO optimized FOPID controller for AGC of nonlinear hydro thermal system with HVDC line

Abstract

This paper presents the fractional order (FO) PID controller (FOPID) for stabilizing the frequency of two similar areas of hydro thermal with constraints of non-linearity. The system is investigated by applying 10% step load burden on area-1. The parametric gains of FOPID controller are optimized with grey wolf optimization (GWO) subjected to error multiplied with time over the integral (ITAE) performance index. Moreover, the superiority performance of FOPID is established by putting system responses with those of conventional controllers under comparison and the GWO algorithms performance is also tested with other algorithms available in literature. Furthermore, the HVDC line is incorporated with the existing AC line in parallel to further damp out system oscillations under load disturbances..