TITLE:
A Novel Multilevel Inverter Employing Additive and Subtractive Topology
AUTHORS:
V. Prasannamoorthy, P. Sundaramoorthi, Merin Jacob
KEYWORDS:
Multilevel Inverter (MLI), Pulse Width Modulation (PWM), Multicarrier PWM Scheme, Additive and Subtractive Topology, Total Harmonic Distortion (THD)
JOURNAL NAME:
Circuits and Systems,
Vol.7 No.9,
July
20,
2016
ABSTRACT: As the demand for high
voltage, high power inverters are increasing and there is a problem of
connecting a power semiconductor switch directly to a high voltage network. As
a part of this the multilevel inverters had been introduced. As a part of this,
several researches had been done for the development of multilevel inverters. The commercially available and
extensively studied topologies for multilevel voltage output are Neutral Point
Clamped (NPC), Cascaded Half Bridge (CHB) and Flying Capacitor (FC) converters.
However, with these existing topologies, there is a significant increase in the
number of power switches and
passive components. Thus it leads to more complex control circuitry and overall cost of the system increase
with increase in the output levels. In this paper, a novel multilevel inverter is
proposed in which it employs additive and subtractive topology to get higher
output levels. This approach significantly reduces the number of power switches
needed as compared to existing topology. The
present developed multilevel inverter can generate only five voltage levels.
With this proposed topology the multilevel inverter can be modified to
nine-level inverter. Moreover modified hybrid multicarrier Pulse Width
Modulation (PWM) technique can be implemented in the proposed multilevel
inverter in order to obtain uniform switch utilization and lower THD. An
appropriate modulation scheme is presented and also the proposed concept is
analyzed through simulation studies.