This paper presents a comprehensive feasibility study of an interleaving approach for a quasi-Z-source inverter. The state-of-the-art approach revealed that an interleaving approach is often used to improve the efficiency and power density that can overcome the problem of oversized passive elements of quasi-Z-source-based converters. The focus is on the application of the interleaving approach in terms of the comparison of several important parameters of a quasi-Z-source inverter. Our analysis includes losses, capacitor and inductor sizes, as well as semiconductor costs. The theoretical comparison is based on the quasi-Z-source inverter model and the losses model. Simulation and experimental verification of theoretical statements are provided. It was found that a 40% reduction of inductor volume, along with 15–20% of efficiency improvements, are achievable. The results are discussed in the conclusion.

No abstract

Постановка проблеми. Із усвідомленням людством своєї відповідальності за погі-ршення стану навколишнього середовища зростає роль відновлюваних джерел енергії. Значне місце серед таких джерел посідає сонячна енергетика. Водночас нагальною стає необхідність збереження електричної енергії. Для її вирішення застосовуються акуму-лятори різноманітних типів. Широкий вибір існуючих на сьогодні акумуляторних бата-рей (АКБ) призводить до необхідності вибору конкретного їх типу для кожного специ-фічного рішення, з урахуванням їх переваг на недоліків.На рис. 1 схематично зображено автономну систему електроживлення. Таку систе-му можна поділити на такі функціональні частини: сонячний модуль, контролер заряду акумуляторної батареї, акумуляторна батарея (АКБ), інвертор напруги та споживач.

Increasing converter power density is a problem of topical interest. This paper discusses an interleaved approach of the efficiency increase in the buck-boost stage of an inverter with unfolding circuit in terms of losses in semiconductors, output voltage ripples and power density. Main trends in the power converter development are reviewed. A losses model was designed and used for the proposed solution to find an optimal number of interleaved cells. It describes static and dynamic losses in semiconductor switches for buck and boost mode. The presented calculation results demonstrate the efficiency of the interleaved approach for photovoltaic system. 1 kW power converter prototype was designed with two parallel dc-dc cells for experimental verification of obtained theoretical results. The experimental results confirm theoretical statements.

The focus of this paper is to provide a comparative analysis of various common-ground converters that serve as dual-purpose power electronic interfaces. These interfaces are designed to be used in both DC and single-phase AC grids, utilizing the same terminals for both modes of operation. The idea lies in the utilization of the same semiconductors in the DC-DC and DC-AC configurations, resulting in minimal redundancy. Particular attention is focused on the comparative evaluation approach. A novel Flying Inductor (FI)-based converter was selected for experimental verification. The design example and experimental prototype of a dual-purpose DC-DC/AC power electronic converter is capable of providing 2 kVA of power in AC mode and 4 kW in DC mode. The experimental results indicate that the converter can operate in both AC and DC grids according to their respective modes. The conclusion of the study highlights the potential applications and main benefits of this technology.