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H. Ertl, J.W. Kolar, F. Zach:
" A Novel Multicell DC-AC Converter for Applications in Renewable Energy Systems";
IEEE Transactions on Industrial Electronics, 49 (2002), 5, ISSN 0278-0046; 1048 - 1057.

This paper presents a novel dc-ac converter for
applications in the area of distributed energy generation systems,
e.g., solar power systems, fuel-cell power systems in combination
with supercapacitor or battery energy storage. The proposed
converter is realized using an isolated multicell topology where
the total ac output of the system is formed by series connection
of several full-bridge converter stages. The dc links of the full
bridges are supplied by individual dc-dc isolation stages which
are arranged in parallel concerning the dc input of the total
system. Therefore, all switching cells of the proposed converter
can be equipped with modern low-voltage high-current power
MOSFETs, which results in an improved efficiency as compared to
conventional isolated dc-ac converters. Furthermore, the cells are
operated in an interleaved pulsewidth-modulation mode which,
in connection with the low voltage level of each cell, significantly
reduces the filtering effort on the ac output of the overall system.
The paper describes the operating principle, analyzes the funda-mental
relationships which are relevant for component selection,
and presents a specific circuit design. Finally, measurements taken
from a 2-kW laboratory model are presented.