FRIT based optimized PI tuning for DC link voltage control of grid connected solar PV system

Abstract

The grid connected photovoltaic (PV) system have been modeled and simulated using control algorithm with dedicated PI control for dc link voltage regulation. Generally, the PI controller used for the system is tuned using trial and error method but this method is having manual limitation for the tuning of controller so as to obtain the desired response like as regulating dc link voltage to reference value. Fictitious reference iterative tuning (FRIT) method using particle swarm optimization (PSO) helps to generate optimized gains for PI controller which can results in the improved response in terms of response time and overshoot. In this paper, PSO-FRIT based optimized tuning of controller is proposed for the application in LCL filter interfaced grid connected PV system. The current controlled dc-ac power converter has been used for grid connected PV system. Active power reference current for pulse width modulated (PWM) converter is been generated using power balance theory (PBT). The idea of the FRIT based optimized tuning of PI controller is implemented by using the input data and output data from the system obtained using the trial and error method based controller gains. The power quality of the system configuration have been maintained as according to the IEEE-519 standards.