A New Fifth-Order Boost Converter With Dual Operating Modes and Wider Conversion Ratios for Renewable Energy Applications

Conventional DC-DC converters for renewable energy systems work in large duty cycle conditions, which will lead to the inductor saturations and decrease the system efficiencies and stabilities. In this brief, a new fifth-order boost converter, which can work in dual operating modes when different control technologies are adopted, is proposed. To obtain a wider conversion ratio, the required duty cycle for the proposed converter with synchronous controller is smaller than 0.333 while with interleaved controller is smaller than 0.5. Also, dual modes of this converter both have lower switches voltage stress. Then, the inductor saturation issues can be avoided and the system efficiencies and stabilities can be improved. Besides, the lower topological order and simple grounded structure of this converter are benefit to reduce the modeling complexity, topology volume and system noises. Detailed analyses, comparisons and prototype are implemented to study the improved conversion ratio, efficiency and power density of the proposed converter in-depth, and to validate its feasibilities for renewable energy applications.