Analysis and modelling of HF-Link Cycloconverter based inverter for low-power renewable energy sources applications

HF-link converters have been studied for several years but they have not been exploited as widely as DC bus based topologies. HF-Link Cycloconverter based topology offers a way to reduce power processing stages redundancy present in conventional DC-bus isolated inverters. However, Cycloconverters have been limited to medium - high power applications because of the complexity associated with their control. Nevertheless, as it is shown in this paper, an appropriated modulation technique like Multiple-Carrier PWM addresses this drawback so that the performance obtained is very similar to a two-level DC-bus inverter. In addition, the mathematical model obtained in averaged state-space and in DQ reference frame shows the system simplicity to apply various control techniques, despite the structural complexity projected by the converter.