HARMONIC REDUCTION IN POWER SYSTEM Ankit Vashi B.E. ...

4.2.3 Multi Level Inverters :
Figure 12: Three Phase Inverter. [7]
Multi level Inverters are a type of inverters whose construction is similar to the
single and three phase inverters as explained earlier. The figure 13 shows a multi level
inverter which is an extension of single and three phase inverters. Here, four IGBT
circuits are connected in three different legs and the diodes are connected in parallel to
each legs in opposite direction. Also, the loads are connected between two IGBT circuits
for each leg as shown in figure.
Advantages of using multi level inverters instead of single and three phase inverters are
as follows : [7]
• Multi level inverters can be used for higher voltage levels
• Also, multi level inverters have higher capability of reducing the harmonics
because of multiple dc levels.
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