An Overview of High-Conversion High-Voltage DC-DC Converters for Electrified Aviation Power Distribution System

This article presents the state-of-the-art review of high-conversion high-voltage (HCHV) dc-dc converters for a modern aerial vehicle's power distribution system. Higher dc bus voltages have become a trend in recent aerial vehicle development because of the potential reduction in size and weight of the rest of the power system and an increase in power density. Some front-end dc energy sources, such as fuel cells, batteries, and supercapacitors, may level at a low voltage and require HCHV dc-dc converters to integrate with the high-voltage dc bus. On the other hand, high-conversion step-down converters are required between the dc bus and various low-voltage electronic loads. A detailed review of HCHV dc-dc converters for an aviation power distribution system is limited in the literature. This article presents two main architectures of such converters. Architecture-I employs individual two-port dc-dc converters to link each source to the dc bus, and Architecture-II uses a single multiport converter (MPC) to connect all the sources to the dc bus. Architecture-I categorizes the two-port dc-dc converter topologies into unidirectional and bidirectional converters, followed by further classifications based on isolation and control schemes. Multiport dc-dc converters for Architecture-II are categorized based on port numbers and then source connection methods. This review investigates multiple topologies within each category or classification, highlighting selected circuit diagrams and their features and shortcomings. This article presents several insightful comparisons, among various bidirectional converters for Architecture-I, and MPCs for Architecture-II, for a designer to choose a proper converter. In terms of converter characteristics, this article focuses on dc voltage gain, power density, efficiency, and reliability, as these qualities are of utmost importance in an aviation application.