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The cost reduction of power-electronic devices, the increase in their reliability, efficiency, and power capability, and lower development times, together with more demanding application requirements, has driven the development of several new inverter topologies recently introduced in the industry, particularly medium-voltage converters. New more complex inverter topologies and new application fields come along with additional control challenges, such as voltage imbalances, power-quality issues, higher efficiency needs, and fault-tolerant operation, which necessarily requires the parallel development of modulation schemes. Therefore, recently, there have been significant advances in the field of modulation of dc/ac converters, which conceptually has been dominated during the last several decades almost exclusively by classic pulse-width modulation (PWM) methods. This paper aims to concentrate and discuss the latest developments on this exciting technology, to provide insight on where the state-of-the-art stands today, and analyze the trends and challenges driving its future. [ABSTRACT FROM PUBLISHER]

This article presents a novel concept of a universal solar converter suitable for application in both in the dc or single-phase ac grids using the same terminals. The idea lies in the utilization of the same semiconductors in the dc–dc and in the dc–ac configuration, resulting in minimal redundancy. Possible semiconductor stages are considered. The particular attention is focused on the output filter design along with proper protection circuit selection for dc and ac grids. The design example and comparative analysis between dc–dc, dc–ac, and universal solutions are given. The experimental prototype of the universal solar converter that is rated for 3.6 kVA power in the ac mode and 5 kW in the dc mode is presented. The experimental results demonstrate the ability of operation in ac or dc grids with main correspondent modes. Possible fields of application along with main benefits are addressed in conclusions. [ABSTRACT FROM AUTHOR]

The article overviews residential and building-integrated photovoltaic (PV) module types. It demonstrates that existing dc–dc converter technologies do not allow building a universal interface microconverter because of wide dispersion of the parameters. However, the absence of universal microconverters limits the widespread adoption of PV modules despite great benefits for energy-efficient buildings and restrains the deployment of residential PV-based dc microgrids. Based on the design requirements formulated, a new approach utilizing a boost half-bridge front-end inverter and a three-mode reconfigurable rectifier (RR) is proposed. The article describes the operating principle of the derived converter. The RR allows keeping the duty cycle of the input side within a favorable range of acceptable efficiencies. An experimental prototype rated for 360 W was assembled and tested in the entire operating range. The experimental results prove the ultrawide input voltage range of over 1:20 and demonstrate the capability of the proposed concept to interface different PV module types while enabling their shade-tolerant operation. [ABSTRACT FROM AUTHOR]