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The enhanced power quality provided by multilevel inverters (MLIs) has made them more appropriate for medium- and high-power applications, including photovoltaic systems. Nevertheless, a prevalent limitation involves the necessity for numerous switches and increased voltage stress across these switches, consequently increasing the overall system cost. To address these challenges, a new 17-level asymmetrical MLI with fewer components and low voltage stress is proposed for the photovoltaic system. This innovative MLI configuration has four direct current (DC) sources and 10 switches. Based on the trinary sequence, the proposed topology uses photovoltaics with boost converters and fuzzy logic controllers as its DC sources. Mathematical equations are used to calculate crucial parameters for this proposed design, including total standing voltage per unit (TSVPU), cost function per level (CF/L), component count per level (CC/L) and voltage stress across the switches. The comparison is conducted by considering switches, DC sources, TSVPU, CF/L, gate driver circuits and CC/L with other existing MLI topologies. The analysis is carried out under various conditions, encompassing different levels of irradiance, variable loads and modulation indices. To reduce the total harmonic distortion of the suggested topology, the phase opposition disposition approach has been incorporated. The suggested framework is simulated in MATLAB®/Simulink®. The results indicate that the proposed topology achieves a well-distributed stress profile across the switches and has CC/L of 1.23, TSVPUof 5 and CF/L of 4.58 and 5.76 with weight coefficients of 0.5 and 1.5, respectively. These values are notably superior to those of existing MLI topologies. Simulation results demonstrate that the proposed topology maintains a consistent output at varying irradiance levels with FLCs and exhibits robust performance under variable loads and diverse modulation indices. Furthermore, the total harmonic distortion achieved with phase opposition disposition is 7.78%, outperforming alternative pulse width modulation techniques. In summary, it provides enhanced performance. Considering this, it is suitable for the photovoltaic system.A 17-level asymmetrical multilevel inverter with fewer components and low voltage stress is proposed for a photovoltaic system. The topology uses photovoltaics with boost converters and fuzzy logic controllers as its DC sources. The analysis is carried out under different levels of irradiance, variable loads and modulation indices.Graphical Abstract

This article studies the bio-convection impacts on Williamson nanofluid flow and covers the nonlinear thermal radiation and chemical reaction effects on stretching sheet. The fundamental focus is to enhance heat transfer. Nanofluids are the most important source of effective heat source, having many applications in scientific and technological processes. Nanomaterials with superior thermal characteristics offer a wide range of uses in medicine, energy generation, heat exchange, and electronic cooling systems, among others. The present physical problem involving this flow is contained the nonlinear partial differential equations (PDEs). An appropriate transformation is used to convert the partial differential equations (PDEs) to ordinary differential equations (ODEs), which are then numerically settled utilizing bvp4c method in MATLAB. The physical features of nanofluids such as fluid velocity, volumetric concentration, temperature, and profiles of motile organisms are studied in relation to various factors. Additionally, the skin friction coefficient, Nusselt number, Sherwood number as well as motile microorganism number are calculated numerically using tables. It is found that the velocity profile decreases for the boosted values of Walliamson fluid parameter, magnetic parameter, angle of inclination and buoyancy ratio parameter. The temperature grows by increasing the values of thermophoresis parameter, exponential space and thermally based heat source/sink parameter. A survey of the available literature corroborates the aforementioned results.