Abstract :
From the viewpoint of high quality output voltage generation in a residential photovoltaic system, a multilevel inverter
employing cascaded transformers can become a good substitute for the conventional pulse width modulated inverters
and other multilevel counterparts. However, to obtain more sinusoidal output voltage waves, it should increase the
number of switching devices and transformers resulting in a cost increase. To alleviate this problem, an efficient switching
pattern is proposed and applied to a multilevel inverter equipped with two cascaded transformers, which have a
series-connected secondary. Operational principle and analysis are illustrated focusing on a change of the switching pattern.
High-performance of the proposed multilevel scheme embedded in a photovoltaic power conditioning system is
verified by computer-aided simulations and experimental results.
2004 Elsevier Ltd. All rights reserved
