Abstract
The application of renewable energy in power generation is steadily increasing. This rapid growth is supported by the recognition of these systems as an effective generation source with positive environmental and economical effects. A key element at the grid side of an isolated system is the inverter. This paper is concerned with the control strategies for three-phase voltage source inverters in PV/Hybrid power systems. The paper will first introduce the power system architecture of the system under study together with the different feeding modes. Further, the three-phase inverter topologies will be shortly discussed. Next, the paper attends to illustrate the control possibilities. The development of a four-leg inverter topology with a new advanced control approach based on symmetrical components is described briefly. Using this power electronics topology in combination with the developed control algorithms, the inverter performance can be improved. Simulation results obtained with the proposed control schemes are also presented.