Control system for dual-mode operation of grid-tied photovoltaic and wind energy conversion systems with active and reactive power injection

Abstract

The purpose of the work is to design and implement a dual mode control operation of grid-connected renewable (photovoltaic or wind) energy conversion systems with a low-voltage ride through capability. Control systems for normal and grid fault condition are presented for the generator and grid sides. In normal grid condition, the dc-dc converter is controlled in order to achieve maximum power extraction, and the inverter is controlled to maintain a constant dc-link voltage and power transfer at a unity power factor. In grid fault condition, the dc-link voltage regulation is achieved by the dc-dc converter and the required active and reactive powers injection are achieved by the inverter to meet the grid code requirements. The proposed control system is experimentally validated for the normal and faulty grid condition with three-phase grid-connected photovoltaic and wind energy conversion system using the OPAL-RT and Festo rapid control prototyping system. Experimental results demonstrate the effectiveness and robustness of the proposed system under different working conditions.