Improved Watkins-Johnson topology-based inverter with dual low-side switch and synchronous control strategy

The full-bridge topology is generally used in the post stage of inverter, to realize dc-ac voltage conversion. Inherent shortcomings of fullbridge such as high-side switch driving, prone to shoot-through and substantial power loss are inevitable. A topological solution is proposed in this letter, by means of improving the original coupled-inductor Watkins-Johnson topology into dual low-side switch version and conducting synchronous control. Theoretical analysis and experimental results indicate that the improved topology is capable of generating pure sinusoidal ac output. The merits include ease of driving, low power loss, nonpulsating terminal currents, immunity to shoot-through, simple control strategy and so forth.