Three-Level Dual Buck Inverter With Coupled-Inductance

Dual Buck inverter (DBI) is a new topology with characteristics of high frequency and high efficiency. Just like half bridge inverter, the output voltage is a bipolar PWM waveform and voltage stress is high. To overcome these problems, a novel three-level dual Buck inverter, which has uni-polar PWM waveforms output and low voltage stress, is proposed. And the half load-cycle mode of DBI remains in the new inverter. However, it may lead to over-voltage when the inductor current is discontinuous. Thus, two inductors of the inverter are coupled together, and the bridge voltage can be clamped, and the size of magnetic component and filter is reduced simultaneously. The topology remains the characteristics of high efficiency and high reliability. Experimental result verifies the analysis described.