Cascaded Multilevel Inverter consist of series of H-bridge (Full Bridge) Inverter units. full-bridge and half-bridge inverter topologies.
The input to the power circuit is a DC source Generally micro controllers generate PWM signals of very low range which is not sufficient for the switches to turn on so a gate driver circuit is designed for that purpose. The main distinctive feature is the digital implementation of the PWM modulation. The circuit of a full bridge inverter consists of 4 diodes and 4 controlled switches as shown below. The switch pairs (Q 1, Q 4) and (Q 2, Q 3) conduct in turn. Now it's time to complete the circuit of Modified Sine Wave Inverter. To verify the presented analysis a 100 W prototype single phase 220 VAC 50 Hz inverter output has been constructed and the experimental results are given. The power rating of DC grid applications is normally greater than 1000W, so full bridge converter configuration is only applicable in these conditions. Full bridge inverter design Fig 1(a) and (b).