Study of the effect of SCR and Controller Gains on system stability in a Grid connected Solar Plant

The renewable energy sources now play a vital role in power generation. The grid connected PV system consists of inverters, power plant controller (PPC) and the grid. The power plant controller measures the quantities from the point of common coupling and regulates the inverters to ensure stable operation of the system. A stability analysis study has been presented in the paper with regards to the short circuit ratio, gains of the inverter and PPC controllers. The study has been presented in terms of pole placement and their movement in the complex plane. The study shows that appropriate tuning of inverter and PPC controllers can provide stable system behaviour even at low SCR conditions.