Single-Stage Soft-Switched partial resonant high frequency AC-link Inverter

In this paper an unidirectional high-frequency ac-link PV-inverter used as an interface between a photovoltaic panel and three phase ac-load will be studied in more detail. This converter belongs to a group of power converters in which the link is formed by a parallel inductance/capacitor. The inductance stores energy from the input and it discharges through the output. The link capacity has the role of soft-switching during both turn-on and turn-off of the switches Because of its variety of configuration this category of converter is named “universal”: inputs and outputs can be ac or dc, mono-phase or multiphase and two-ports or multi-ports. These converters have several advantages over the other types of converters that make them an excellent choice for use in renewable energy systems in standalone and grid-connected applications and for use in electric and hybrid-electric vehicles. Compared with other topologies, these ac-link converters are compact, reliable, efficient, they guaranty longer lifetime and can be used for bidirectional power flow. In this paper, the principles of operation of the ac-link PV-inverter will be clearly explained and simulations results under MATLAB/SIMULINK will be shown to validate the operation of the converter topology. Finally, detailed analysis will be carried out.