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High step-up dc–dc converters are widely used in new energy applications such as photovoltaic cell, fuel cell, dc microgrid, etc. Active switched-inductor (ASL) converter has simple operation and low stress on switches. To further increase the voltage gain, some SC (switched-capacitor)/ASL step-up converters have been proposed recently. However, these SC/ASL step-up converters have voltage oscillation on switches, which leads to the voltage stress on switches is higher than the theoretical value. In this article, a novel high step-up SC/ASL converter is proposed. Compared with other SC/ASL step-up converters, the proposed converter has lower voltage stress on the switches, output diodes, and output filter capacitors, and the efficiency is higher. In addition, the proposed converter can achieve self-voltage balancing on switches. This article analyzes the proposed converter from operation principle, continuous conduction mode (CCM) analysis, CCM operation with unbalanced inductors, input current ripple analysis, discontinuous conduction mode and boundary conduction mode analysis, switches self-voltage balancing characteristic, voltage stress, current stress, comparison analysis, and design considerations. Finally, a 200 W, 25–45 V/380 V, 50 kHz experimental prototype has been established in the laboratory to evaluate the proposed converter, which reached a peak efficiency of 97.3%. [ABSTRACT FROM AUTHOR]

Passive daytime radiant cooling (PDRC) technology is an energy-free and ecologically beneficial cooling solution compared to conventional electric cooling. The limited cooling efficiency and impossibility of mass manufacture, however, severely restrict its popularization and application. This study uses a combination of template and etching techniques to construct a hierarchically porous Poly (vinylidene fluoride-co-hexafluoropropene) (P(VDF-HFP) coating with controlled pore size and porosity. Coated textiles have strong solar reflectances (0.93) and infrared emittances (0.98) thanks to the organization of specific micro-nano multi-level pore size and high porosity, which results in a subambient temperature drop of around 9.0 °C. Due to its porous structure, the coated textile possesses a considerable bit of flexibility and self-cleaning capabilities. The present work paves a new way for the mass production of radiate cooling textiles with a controlled coating structure and exceptional cooling performance. [Display omitted] • Radiation cooling textiles are prepared by stencilling and etching to form layered porous structures. • The coated textile has a solar reflectivity of 93% and an ultra-high atmospheric transparent window emissivity of 98%. • Sub ambient cooling of 9.3 °C can be achieved during daylight hours with the coated textile. • In addition to the radiative cooling properties, the coated textiles are also self-cleaning. [ABSTRACT FROM AUTHOR]