الفهرس 
multilevel technology
multilevel inverter topologyOnly 14 pages are availabe for public view
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Abstract
In recent vears. industrv has begun to demand higher
power equipment. which now reaches the megawatt level.
Controlled ac drives in the megawatt range an? usually connected
to the medium-voltage network. Today. it is hard to connect ~l
single power semiconductor switch directly to medium-voltage
grids. For these reasons, a new family of multilcvel inverters has
emerged as a solution for working with higher voltage levels. In
the last fc\\ years. interest in multi-phase multi-level inverter
technology has increased due to the benefits of using more than
three phases in drive applications. Most of the variable-speed
electric drives use three phase machines. Nevertheless. since
variable-speed ac drives include a power electronic converter. the
number of machine phases can be higher than three. Major
advantages of using a multi phase machine instead of a standard
three-phase one are: Improved reliability and increased fault
tolerance. greater efficiency, higher torque density and reduced
torque pulsations. lower per phase ]1O\\er handling requirements.
enhanced modularity. and improved noise characteristics. The
work in this dissertation is divided into the following major parts: