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Future transportation will replace the current mechanical combustible engines with chargeable electric vehicles (EVs). The DC-Dc boost converter is an essential part of such systems that not only helps to generate the required level but also helps to regulate the load voltage. In conventional boost converter topologies, their gain, switching losses, and high voltage stress across switches are the main reason for limiting the output power. Coupled inductor-based isolated converters increase the system weight and cost. Therefore, in this paper, a transformerless adjustable gain and non-isolated DC-DC boost converter with multi-port flexible power supply, reduced switch voltage stress, and considerable good range efficiency is proposed. The proposed converter is tested with the 100 W resistive load to test the desired characteristics. [ABSTRACT FROM AUTHOR]

This paper presented an analytical and closed-form solution for the harmonic contents that were injected in the five-level inverters from asymmetrical DC sources or batteries which were suitable for renewable energy sources. In the five-level inverters, two DC sources V1 and V2 were used to synthesize the output voltage. Therefore, two transcendental equations were formulated for the fundamental and the third harmonic orders based on the unequal DC sources V1 and V2. These transcendental equations were solved analytically for low switching control technique. The proposed solution included the modulation index change which resulted in changing the fundamental component. Therefore, two switching angles are formulated and solved analytically to control the amplitude of the fundamental voltage and cancel the third order harmonic. A well-known third order equation was generated. Thus, a closed-form solution for the above two switching angles will be generated in terms of the modulation index. The proposed solution was tested for a wide range of V1/V2 ratio. Some selected simulation and experimental results were provided to validate the proposed method for wide ranges of both modulation index and V1/V2 ratio. [ABSTRACT FROM AUTHOR]

The aim of this work was to study the application of design of experiment (DoE) approach in defining design space for granulation and tableting processes using a novel gentle-wing high-shear granulator. According to quality-by-design (QbD) prospective, critical attributes of granules, and tablets should be ensured by manufacturing process design. A face-centered central composite design has been employed in order to investigate the effect of water amount (X1), impeller speed (X2), wet massing time (X3), and water addition rate (X4) as independent process variables on granules and tablets characteristics. Acetaminophen was used as a model drug and granulation experiments were carried out using dry addition of povidone k30. The dried granules have been analyzed for their size distribution, density, and flow pattern. Additionally, the produced tablets have been investigated for; weight uniformity, breaking force, friability and percent capping, disintegration time, and drug dissolution. Results of regression analysis showed that water amount, impeller speed and wet massing time have significant (p < .05) effect on granules and tablets characteristics. However, the water amount had the most pronounced effect as indicated by its higher parameter estimate. On the other hand, water addition rate showed a minimal impact on granules and tablets properties. In conclusion, water amount, impeller speed, and wet massing time could be considered as critical process variables. Thus, understanding the relationship between these variables and quality attributes of granules and corresponding tablets provides the basis for adjusting granulation variables in order to optimize product performance. [ABSTRACT FROM AUTHOR]

In this article, a new single-stage high boosting ratio converter for grid-connected photovoltaic systems is proposed. The proposed system consists of a high voltage gain switched inductor buck-boost inverter that employs a folded cascade H-bridge circuit and operates at line frequency. The proposed system has a single switch operated with a sine wave modulation control. This applied control achieves maximum power point tracking of the input photovoltaic system in addition to the required injected sinusoidal grid current. The proposed system achieves the highest voltage boosting ratio of transformer-less topologies to the authors' best knowledge—more than ten times. In addition, it lowers switching losses and reduces the ground leakage current. A 150-W prototype with input voltage of 20 V and output voltage of 240 V has been developed with the purpose of obtaining experimental results and validating the proposed topology. Results report a boosting voltage gain of about ten times and system efficiency above 85%. [ABSTRACT FROM AUTHOR]