CONTROL OF PHOTOVOLTAIC FED INVERTERS FOR EFFECTIVE INTEGRATION OF Ps INTO AUTONOMOUS HYBRID POWER PLANTS

Athanassios D. Karlis - Demetrios P. Papadopoulos - Vojtech Veselý

   This paper presents a new methodology for controlling an inverter used to invert and transfer power from photovoltaic and battery storage devices to an autonomous power grid. PVs and batteries are viewed as active devices used to improve system stability. The purpose of this approach is to effectively dump out any disturbances caused on the utility system by modulating the output power of the overall conditioning system (ie by injecting appropriate amount of power into the grid). The automatic control system monitors oscillating quantities of the power system, such as load, frequency and grid's voltage fluctuations. Successful implementation of this control method relies heavily on an appropriate tuning of the several control branches. Simulation studies, using the proposed control method, indicate that the application of such an approach improves power quality and stability of the interconnected system and is applicable to any PV penetration levels.

Keywords: hybrid autonomous power systems, grid-connected photovoltaic and battery systems, inverters, control systems, transient stability analysis

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