Modeling and Implementation of Serial-Parallel-Switched-Capacitor Coupled-Inductor DC-AC Inverter

Abstract

The modeling and implementation of a serial-parallel-switched-capacitor coupled-inductor inverter (SPSCCI) is presented by incorporating sinusoidal pulse-width-modulation-based (SPWM) controller for realizing high-gain DC-AC conversion/closed-loop regulation. Its power part consists of 2 cascaded blocks: SPSCCI booster (coupled inductor with turn ratio n, 4 pumping capacitors, 5 switches) and half-bridge DC-link (HBDL) inverter (2 bridge capacitors, 2 switches), so as to boost a voltage gain range into: +0.5[4(n+1) + (nD + 1)/(1-D)] ~ 0.5[4(n+1)+(nD + 1)/(1-D)] (D: ratio cycle). When n = 4, D = 0.5, AC output can be boosted into +13~13 times voltage of DC supply. Its control part consists of an SPWM compensator and a phase generator, implemented mainly on a full-custom chip: D35-105B-E0008, TSMC 0.35μm 2P4M, 1500μm×1500μm, 5V, 2.68mW, max. 200kHz. Here, the related modeling and analysis are discussed. Finally, the simulation/experiment results of SPSCCI are presented and verified on a prototype board to demonstrate the practicality of this scheme.