ABSTRACT The inverter can be categorized as two level conventional inverter
and multilevel inverter (MLI). These two level (conventional)
inverters have many drawbacks particularly for high voltage and
high power applications.
The MLI is able to provide more number of levels in the output. The
harmonics are greatly reduced with increase in levels and output
voltage waveform approaches to sine wave.
The MLI requires more components to produce more number of
levels in the output.
This paper deals with, the study of Asymmetrical configuration for
seven level and nine level H-bridge multilevel inverter. The
simulations for five level symmetrical, seven level symmetrical and
asymmetrical and nine level asymmetrical configurations are carried
out in MATLAB. It is observed that, asymmetric MLI has ability to
provide more pure output without increasing the structure compared
to symmetrical MLI.
THD and Vdc values for output line voltage of
COMPARISON OF MLIType of Inverter No. of Switches No. of DC Sources
CONCLUSIONFrom the simulation results it is concluded
that, by taking different geometric progression
factor the output levels of Asymmetrical MLI can
be increased without any increased in
components. So the output of ACMLI has very
less amount of harmonic content i.e., the output
is smoother. As compare to SCMLI, the numbers
of bridges, DC sources required in ACMLI are
less for attaining same number of levels. So the
problem of requirement of more components to
achieve more number of output levels are
eliminated with proposed ACMLI topology.
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