Implementation of three level H-bridge cascaded multilevel inverter by using AVR microcontroller for SPWM technique

The multilevel inverters are basically classified as diode clamped, flying capacitor inverter and cascaded multi-level inverter. The cascaded multilevel control method is comparatively easy to other multilevel inverter because cascaded multilevel inverter do not require any clamping diode and flying capacitor. The simulation had been carried for three level cascaded H-bridge multilevel inverter (MLI) by using DC power source with advance control pulses. The main objective of this paper was to analyze three level H-bridges MLI for gate pulses generated by AVR microcontroller which reduces total harmonic distortion and enhances output voltage without adding any complexity to the power circuit and control circuit. Gating signals for these insulated-gate bipolar transistors (IGBTs) have been generated by using AVR microcontroller. In order to maintain the different voltage levels at appropriate intervals, the conduction time intervals of IGBTs have been maintained by controlling the pulse width of gating pulses.