An 8-Level Stacked Dual-Active-Half-Bridge Partial Power Processing DC/DC Converter

Power converters that process less power than they output, also known as partial power processing converters (PP-PCs), are an area of increasing study, driven largely by society's demand for power dense and efficient electronics. Concurrently, there is also a shift towards higher voltages as mass adoption of EVs and renewable energy sources continues. This paper presents a multilevel PPPC topology, aimed to satisfy the demand for both higher voltages and higher efficiencies. Analysis is provided in the context of the Manhattan topology, a multilevel converter topology defined by a set of series stacked capacitors where there exists a scheme to transfer power between each capacitor in the stack. Governing dynamic equations are derived alongside a feedforward dominated control scheme. The work is experimentally validated with an 8-level, 800V input, 6.5kW 98.7% peak efficiency converter implemented in GaN with a switching frequency of 1MHz. Partial power processing and controlled distribution of the input voltage amongst the eight levels are experimentally proven. Lastly, transient, steady-state, and efficiency results for a range of operating points are provided.