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© The Institution of Engineering and Technology 2020. A new simplified control scheme is proposed for AC–DC electrolytic capacitor-less converters operating in continuous conduction mode (CCM). The proposed method has a single-loop controller responsible for both regulation and power factor correction (PFC). In comparison with the two-loop conventional CCM current mode controller, the proposed scheme does not need a multiplier or extra sensors hence simplifying the control circuitry and its design procedures. Modelling of the closed-loop converter is addressed and experimental results are provided to show the feasibility of the control scheme.

© 2020 by the authors. Microinverters are an essential part of the photovoltaic (PV) industry with significant exponential prevalence in new PV module architectures. However, electrolyte capacitors used to decouple double line frequency make the single-phase microinverters topologies the slightest unit in this promising industry. Three-phase microinverter topologies are the new trend in this industry because they do not have double-line frequency problems and they do not need the use of electrolyte capacitors. Moreover, these topologies can provide additional features such as four-wire operation. This paper presents a detailed discussion of the strong points of three-phase microinverters compared to single-phase counterparts. The developed topologies of three-phase microinverters are presented and evaluated based on a new classification based on the simplest topologies among dozens of existing inverters. Moreover, the paper considers the required standardized features of PV, grid, and the microinverter topology. These features have been classified as mandatory and essential. Examples of the considered features for classifications are Distributed Maximum Power Point Tracking (DMPPT), voltage boosting gain, and four-wire operation. The developed classification is used to identify the merits and demerits of the classified inverter topologies. Finally, a recommendation is given based on the classified features, chosen inverter topologies, and associated features.

© 2020 by the authors. The increase in operating temperature of PV generators leads to degradation of their performance. These adverse effects of high temperatures are considered as one of the most important problems that solar panel operation faces in hot weather areas. Alot of research has been undertaken to study this aspect and find ways of limiting the harm caused by such high temperatures. To overcome this harm and to maintain the operating temperature of the PV cells within the optimum range specified by manufacturers, cooling the solar panels often becomes indispensable. This paper discusses the heat transfer through the solar panel layers and studies the effect of high temperature on the solar panel performance in a hot desert environment. It also presents the development of a new solar panel structure viz. by installing an aluminum heat sink to reduce the effect of temperature rise and thus improve the solar panel performance. The study focuses on a pole-mounted solar panel for a street lighting apparatus in extremely hot desert conditions with fluctuating wind speeds. It will be shown that adding an aluminum heat sink to the solar panel bottom mitigates the effect of increased temperature and hence modifies the solar panel operating point by increasing both the efficiency and the lifetime. The solar cell temperature is decreased by 16.4% as a result of the aluminum heat sink installation on the solar panel back sheet and consequently, the accumulated energy produced by the the solar panel is increased by 13.23% per day.

© 2019 by the authors. This paper presents a multi-input Ćuk-derived Buck-Boost voltage source inverter (CBBVSI) for Photovoltaic (PV) systems. The proposed topology consists of a single-stage DC-AC inverter that combines both DC-DC and DC-AC stages. The DC-DC stage is used for stepping-up the voltage from the PV generator. Simultaneously, the DC-AC stage is used for interfacing the PV source with the AC grid. The topology allows three sources to utilize the antiparallel diodes for each inverter leg for transferring the energy. The proposed system exhibits several features such as a reduction of the number of components compared to typical two-stage structures, and Split-Source Inverter (SSI), and Z-Source Inverter (ZSI) topologies. Moreover, the power of each PV source can be harvested either simultaneously or separately since independent Maximum Power Point Tracking (MPPT) is performed. The system was simulated using MATLAB/SIMULINK software and a 1 kW laboratory prototype was implemented to verify the operation of the proposed CBBVSI. The numerical simulations are presented together with the experimental results, showing a good agreement.