The document presents a new topology for a submultilevel inverter and proposes connecting multiple submultilevel inverters in series to create a generalized multilevel inverter. The proposed multilevel inverter uses fewer switching devices than existing topologies and is analyzed under symmetric and asymmetric conditions. Simulation results using MATLAB-SIMULINK show the asymmetric 31-level inverter has distortion of only 0.2% using 12 switches, while the symmetric 13-level inverter has 0.8% distortion using 16 switches.

1. UNDER THE GUIDENCE OF
PRESENTED BY
P.RAJENDAR
B.SATHYANARAYANA(10QK1A0227)
(Asst.prof.)
P.SHIVA KUMAR
(10QK1A0229)
N.SHRAVAN KUMAR (10QK1A0231)

2. Introduction :

In this project, initially a new topology for submultilevel inverter is
presented and then series connection of the submultilevel inverters is
proposed as a generalized multilevel inverter.
 The proposed multilevel inverter uses reduced number of switching
devices and has been analyzed in both symmetric and asymmetric
conditions.
 Simulation is implemented using MATLAB-SIMULINK and the results are
presented. The Asymmetrical 31-level inverter using 12 switches has
distortion of only 0.2% and 13-level symmetrical inverter using 16
switches shows 0.8%.

3. In one simple inverter circuit, DC power is
connected to a transformer through the center
tap of the primary winding.
 A switch is rapidly switched back and forth to
allow current to flow back to the DC source
following two alternate paths through one end of
the primary winding and then the other.
 The alternation of the direction of current in the
primary winding of the transformer produces
alternating current (AC) in the secondary circuit.


4. EXISTING SYSTEM TECHNIQUE
There are three well-known types of multilevel inverters
 the neutral point clamped (NPC) multilevel inverter,
 the flying capacitor (FC) multilevel inverter, and
 the cascaded H-bridge (CHB) multilevel inverter.

6. PROPOSED SYSTEM TECHNIQUE
 In the symmetric topology, the values of all of the dc voltage sources are
equal. This characteristic gives the topology good modularity.
However, the number of the switching devices rapidly increases by
increasing the number of output voltage level.
 In order to increase the number of output voltage level, the values of the
dc voltage sources are selected to be different, these topologies are
called asymmetric.

7. Block diagram:
DC supply
MLI
CONTROL
SIGNAL
TO LOAD

8. ADVANTAGES
• Less switching devices are used.
• Switching losses are low.
• Efficiency is high.
• Control scheme is simple.

9. APPLICATIONS
 Pump, fans, compressors.
 Photovoltaic power-conversion system.
 Wind power conversion.