In this study, the authors present a 5 W wireless battery charger for handheld devices. Efficiency-related issues are addressed. A power receiver architecture which improves power conversion efficiency is proposed. Design hints are provided for further applications. Comparison with a conventional architecture is provided as well. Laboratory prototypes of both the proposed and the conventional architectures have been realised. Both prototypes are tested by using the same power transmitter to perform a valuable comparison. As shown by the experimental results, in the receiver side power conversion efficiency is increased up to 99% thanks to the proposed solution.

Sustainability of current energy policies and their mid-term outlooks are investigated. First, an overview is given about the trend of global energy demand and energy production. The share of energy sources and the geographic distribution of demand are analysed on the basis of the statistics and projections published by major agencies. Sustainability of selected renewable energy sources is then explored. Finally, potential use of Hydrogen for energy storage in systems with high share of renewable sources is investigated.

A dynamic dead time controller is presented, specifically intended to operate in synchronous boost converters based on GaN field-effect transistor switches. These transistors have a reduced stored charge with respect to silicon metal-oxide-semiconductor field-effect transistors with similar breakdown voltage and series resistance, and can operate at higher frequencies with reduced switching losses. On the other hand, the voltage drop in reverse conduction is typically more than doubled with respect to silicon devices resulting in relevant power losses during the free-wheeling phases. Therefore, dynamic control of dead time can be profitably applied even in converters operating in the tens of volts range. The device presented in this study controls the switching delays taking into account both variations of the fall/rise times and of the turn-off/on delays, in order to keep dead time within a range of a few nanoseconds above its minimum value. A discrete-component prototype was designed, built in a synchronous boost converter and extensively tested at 1-2MHz switching frequency, in a range of operating parameters corresponding to significant variations of the switching times (currents in the 1-6A range, output voltage up to 50V). The prototype demonstrated the capability to match dead time to actual operating conditions with a smooth and fast transient response

The diffusion of electric vehicles in Italy has started but some complications weight its spread. At present, hybrid technology is the most followed by users, due particularly to socioeconomic factors such as cost of investment and range anxiety. After a deep discussion of the Italian scenario, the aim of the paper is to recognize whether fuel cell technology may be an enabling solution to overcome pollution problems and respect for the environment. The opportunity to use fuel cells to store electric energy is quite fascinating—the charging times will be shortened and heavy passenger transport should be effortless challenged. On the basis of the present history and by investigating the available information, this work reports the current e-mobility state in Italy and forecasts the cities in which a fuel cell charging infrastructure should be more profitable, with the intention of granting a measured outlook on the plausible development of this actual niche market.

Charging equipment for all-Electric Vehicles (EVs) is classified by the rate at which the batteries are charged. Charging times vary based on how depleted the battery is, how much energy it holds, the type of battery, and the type of Electric Vehicle Supply Equipment (EVSE). In this paper, a review of the innovative charging stations is reported