Impact of large photovoltaic power penetration on the voltage regulation and dynamic performance of the Tunisian power system

By the year 2023, the Tunisian power transmission grid has been projected to include photovoltaic pool of power of 937 MW, scattered throughout the whole landscape of the nation. This paper investigates high photovoltaic energy penetration impacts voltage regulation and dynamic performance of the grid. Load flow analysis is implemented to investigate the power system capability for the case of incorporating the desired photovoltaic power. Computer-based simulations have been used for evaluating the upgradation of the grid. Moreover, the study is based on bifurcation diagrams taking the photovoltaic generation as a bifurcation parameter and time response simulations to grid disturbances. Professional PSAT simulation toolbox has been used for the power flow simulation studies. Network- related faults like outage of photovoltaic farm event, three-phase short-circuit at a conventional bus, and voltage dip at the largest photovoltaic station have been considered. It is hoped that the results of the presented study would benefit Tunisian’s utility’s policies on integration of PV systems. Moreover, this comprehensive analysis and study will be a valuable guide for assessing and improving the performance of national grid systems of any other countries also, that gives the huge potential and need for solar energy penetration into the grid systems.