Design and analysis of coupled-inductor Cockcroft–Walton-switched-capacitor boost DC–AC inverter

ABSTRACT

The objective of this study is to present a novel simple structure of coupled-inductor Cockcroft–Walton-switched-capacitor (CICWSC) inverter for DC–AC conversion/closed-loop regulation. In structure, the power part is contained by three units: coupled–inductor booster, Cockcroft–Walton-switched-capacitor doubler, and half-bridge DC-link, working together for providing the DC–AC gain range as $+\left(n+1\right)/(1-Dgt)\sim -\left(n+1\right)/\left(1-D\right)$ (n: turn ratio, $D$: ratio cycle). In control, for the time sequence (to different topologies) and output regulation/robustness (to various desired output/loading variation), the control part is made of phase generator and sinusoidal pulse-width-modulation (SPWM) block, and its chip internal circuit is designed through pre/post-layout procedure via CADENCE. By the assistance of Chip Design and Implementation Center (CIC) and TSMC, this control part is practically fabricated on a real chip (D35-104B-E0013, TSMC 0.35μm, 2P4M, 3.3V, 3.889mW). In analysis and design, the quantitative mathematical modeling of CICWSC is carefully derived, and the relevant system analysis/ design is also presented (e.g. steady-state response, conversion ratio, power efficiency, parameter selection, stability, and control design). In implementation, it contains several cases of simulation and experiment (via testing on prototype circuit) so as to examine the validity of the analysis/design and check the efficacy of the proposed structure.

KEYWORDS:

• Coupled-inductor
• Cockcroft-Walton-switched-capacitor
• boost DC-AC conversion
• closed-loop regulation
• sinusoidal pulse-width-modulation

Acknowledgments

The study of converter theory and application has the funding support from the Ministry of Science and Technology (MOST) of Taiwan, R.O.C., under Grant MOST 109-2221-E-324-027.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Ministry of Science and Technology (MOST) of Taiwan [MOST 109-2221-E-324-027].