Optimized Cascade Fractional Order Controller for PV Systems

Abstract

Controlling and managing PV systems has been an open research subject for two decades. Regulating the operating point of a PV system requires acceptable closed-loop dynamic behavior. This paper proposes a cascade fractional order proportional integral derivative (FOPID) controller for voltage regulation of PV systems. The controller is optimized using the particle swarm optimization (PSO) algorithm, with the integral square error (ISE) as the fitness function. Excellent results were obtained, demonstrating that the proposed controller has the capability to operate in different working regions, especially in the constant current region where the oscillatory response must be reduced. The cascade controller has a significant impact on improving the dynamics of the PV system, as it can handle internal disturbances caused by the nonlinear relationship of PV current.