Designing Imbricated Cells Multilevel Inverter using Naturally Sampled Sine-Triangle PWM

Multilevel inverters have been attracting attention in recent years due to high power quality, high-voltage capability, low switching losses, and low EMC concerns. Hence a detailed work has been done on the design and performance study of a three-phase five-level imbricated cells PWM inverter. The heavy and bulky transformers that have been used in traditional inverters are eliminated completely from the system. Sine-triangle pulse width modulation technique has been used to generate the switching signal of the inverter. Harmonic analysis with modulation index and frequency modulation ratio has been done and found that as the carrier frequency increases the harmonics are shifted to higher frequency region. An LC filter is used to minimize the harmonic distortion at a tolerable value