Improved two‐stage boost inverter with integrated control strategy

Abstract

In this study, an integrated control strategy is proposed which can be widely used in two-stage boost inverters, and an improved two-stage boost inverter is taken as an example to present the proposed integrated control idea. The presented inverter can operate in four quadrants, which can realise grid-connected or stand-alone inverter. With improved control strategy, it not only can reduce the number of switching times and improve the efficiency but also can reduce the harmonic contents of bridge arm voltage and further decrease the volume and weight of the filter. Therefore, the presented inverter still has the advantages in efficiency and volume when compared with single-stage boost inverters. The operating principle, harmonic analysis, simulation and experiments are provided in this study. A 500 W prototype is established and tested, and the results of simulation and experiments verify the correctness of the theoretical analysis.

Two‐stage off‐grid system for catering household AC appliances with reduced switches

“…For off‐grid appliances, the dc output of the PV has to be converted into ac at the desired output voltage and frequency. The major challenges to be addressed during the implementation of PV‐based off‐grid schemes are as follows [5–10]: (i) efficient dc to ac power conversion from PV and/or battery with voltage boosting; (ii) maximum power point tracking (MPPT) control of the PV array; (iii) proper protection of the battery and charge control; and (iv) regulation of ac voltage and the frequency at the load side.…”