Modular multilevel converter-based microgrid : a critical review

Recently, the Modular Multilevel Converter (MMC) has drawn significant attention due to its diverse merits and its applicability to a wide range of medium to high-power applications. The growing interest in the MMC can be attributed to its attractive features such as modularity, reliability, and high voltage capability. Significant research has been conducted on the MMC over the last few years to develop its operation and control in various applications. However, the application of MMCs in microgrids remains a largely unexplored topic. Therefore, this paper aims to address this research gap by offering an in-depth review of the latest developments concerning circuit topologies, control schemes, and fault-tolerance strategies of MMC within microgrid applications. This comprehensive review not only provides a synthesized overview of the current state of the art but also paves the way for future investigations in this promising field. The outcomes from this study are expected to stimulate further advancements in MMC applications in microgrid systems, thus contributing to the continuous improvement and evolution of microgrids.University of Sharjahhttps://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=6287639Electrical, Electronic and Computer Engineerin

Energy and exergy assessment for a University of Sharjah’s PV grid-connected system based on experimental for harsh terrestrial conditions

Solar PV technology’s growth is fast and widespread in the United Arab Emirates (UAE), even though UAE has harsh climate conditions, ambient temperature, irradiance, and humidity are very high during most of the year. These conditions affect the performance and lifespan of the PV systems installed in the UAE. The current work aims to comprehensively assess the performance of a PV system installed in Sharjah city in UAE in different year seasons. A complete experimental setup for a 2.88 kW PV grid-connected system under the terrestrial conditions of Sharjah city is established. Exergy analysis procedure are performed based on the second law of thermodynamics which presents a different and informative means of evaluating and comparing PV systems reasonably and implicitly. Exergy analysis yields efficiencies that show how nearly actual performance methods recognize more clearly than energy analysis the causes and locations of thermodynamic losses. The results show that January has the highest efficiency while July has the lowest efficiency due to the highest ambient temperature in July. Furthermore, the lowest PV module temperature and highest electrical efficiency obtain at low and high ambient temperatures and highest wind speed. At the same time, the highest electrical power exists at low ambient temperature and the high irradiance value. The highest average PV exergy of 15.34% and lowest average PV exergy of 11.80% were detected in January and July, respectively. The low ambient temperatures in January courses reduced low thermal losses and kept the PV model temperature. However, the low solar radiation limited the conversion yield of the PV system

Experimental and numerical simulation of a 2.88 kW PV grid-connected system under the terrestrial conditions of Sharjah city

Solar PV technology is rapidly and widely expanding throughout the world, particularly in the United Arab Emirates (UAE). The UAE has harsh climate conditions, with high ambient temperature, irradiance, and humidity for most of the year. In this study, three-dimensional numerical simulations were run for a 2.88 kW PV grid-connected system in Sharjah, UAE, under actual conditions. The experimental and mathematical results for PV module temperature and electrical power are compared. The parametric study looks at how weather conditions affect system temperature, electrical efficiency, and power. Furthermore, the current research determined the cooling requirements for such PV systems in a variety of terrestrial conditions. To determine how ambient temperature and wind speed affect PV module temperature, electrical efficiency, and electrical output under various irradiance levels, a parametric study was conducted. The findings demonstrate that at low irradiance, low and high ambient temperatures and wind speeds, respectively, yield the lowest PV module temperature and maximum electrical efficiency. High irradiance values have no effect on wind speed, but low ambient temperatures have the most electrical power. Back cooling must be at least 200 W/m2 K to maintain an electrical efficiency of roughly 14.75%. The reduction of the highest temperature at the center of the cell of the 2.88 kW PV grid-connected system by using back cooling reduces by 26 °C for the worse case season where the highest temperature occurs

Experimental investigation of the effect of optical filters on the performance of the solar photovoltaic system

Researchers are becoming more interested in renewable energies as a viable answer for today’s energy needs due to the rising demand for energy and climate changes brought on by the use of fossil fuel resources. One of the most significant sources of renewable energy is solar energy. Photovoltaic systems are used to convert the received solar radiation to electricity. Low overall performance throughout the operational time caused by raising the solar cells’ temperature is one of the most significant problems with the use of photovoltaic systems. In this experimental work, the influence of optical filters on the performance of photovoltaic panels was studied under Sharjah meteorological conditions. In this study, a 50 W solar PV module’s outdoor performance characteristics were analyzed. This case study employed a Plexiglas sheet, a box filled with air and water, and affixed it directly to the top surface of the PV panel to demonstrate the impact of the Plexiglas as an optical filter on the electrical productivity of the PV panel in relation to the variation in temperature caused by the filters. By imposing optical filters, and therefore lowering the temperature of the system, this work shows promising results in boosting the performance of the PV module. Module current drops dramatically as solar irradiance is blocked, yet panel voltage rises for filter-covered panels compared to the reference panel. In terms of fill factor and electrical efficiency, there has been a noticeable improvement. The voltage at maximum power, electrical efficiency, and maximum output power increased significantly. The average efficiencies of a reference PV module, a plexiglass-sheet-covered PV module, and a plexiglass-air-box-covered PV module are 7.02%, 7.5%, and 8.12%, respectively. In comparison to the reference module’s average efficiency of 6.66%, the covered PV module with plexiglass water box averages 6.74