Dual-Output Hybrid Direct AC–AC Converter Based on Boost Converter and Switched-Capacitor With Voltage Doubling Capability

A dual-output hybrid direct AC-AC converter with output voltage-doubling capability is outlined in this article. The main idea of proposed topology is the combination of a boost converter and symmetrically configured switched-capacitor cells. It not only inherits the superiority of high output voltage gain from the switched-capacitor, but also retains the benefit of wide range adjustable output voltage from the boost converter. Operating as an AC-AC solid-state autotransformer, the converter exhibits greater advantages in volume and copper consumption compared to bulky traditional autotransformers. The converter with direct energy conversion relies on neither bidirectional switches nor electrolytic capacitors, and it can achieve steady-state operation through simple PWM modulation. The other advantages of the proposed converter are the low voltage stresses across the components and self-balancing ability of capacitor voltages. The operating principles of this converter, the quantitative analysis, and the design considerations for the key parameters are described in detail. Finally, the feasibility of the proposed topology is corroborated by experimental results of the single-phase prototype with dual-output ports and 1.5-kW rated power at 50 Hz.