Novel controller design for DC link voltage control of grid connected PV system and optimized PI response analysis with improved transients

The grid connected PV system is having dedicated controller for dc link voltage control with control algorithm for generation of reference quantity. The degree of freedom in the system with PI control scheme is having one degree of freedom (DOF). The normal PI controller (1-DOF PI) deals with the limitation of having single proportional and integral gains that may results in poor response time and overshoot. In this paper the 2-DOF concept based PI controller configuration has been implemented for the dc link voltage control. It is based upon the concept to increase the DOF in the system. The system with 2-DOF PI controller having two DOF with two proportional gains and one integral gains (PI-P). The gains of 1-DOF PI controller is been optimized using fictitious reference iterative tuning (FRIT) method. The performance of the PIP controller has been compared with the optimized and non-optimized PI controller response based upon the improvement in transient response while PV system is connected to grid and under disturbance.