Control of Grid-Connected and Intentional Islanding Operations of Photo Voltaic System

Existing control techniques for DG systems are designed to operate a system either in the connected or disconnected (islanding) mode to the utility; thus not allowing for both modes to be implemented and transitioned between. Existing detection and re-closure algorithms can also be improved upon. Dependent upon the method implemented, detection algorithms can either cause distortions in the output or completely miss a disturbance. The present reclosure process to reconnect to the utility is to completely shut-down and wait five minutes. The proposed methods of this study improve upon existing methods, via simulation and hardware experimentation, for DG systems that can intentionally islanding themselves. In this paper, the control, islanding detection, load shedding, and reclosure algorithms have been proposed for the operation of grid-connected and intentional-islanding DGs. This paper describes a control strategy that is used to implement grid-connected and intentional-islanding operations of distributed power generation. This paper proposes an intelligent load-shedding algorithm for intentional islanding and an algorithm of synchronization for grid reconnection. A Simulink based model is developed and the simulation results for the proposed model are obtained by using MAT LAB. KeywordsDistributed generation (DG), grid-connected operation, intentional-islanding operation, load shedding, synchronization, photovoltaic cell.