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Recently, the improvement of the semiconductor devices to achieve higher efficiency and higher power density has risen to interest. Si carbide and gallium nitride offer faster switching frequency and lower losses; however, the knowledge of the behaviour of these devices is not mature. In this paper, a system for fast charging of batteries for electric vehicles based on an isolated DC-DC converter equipped with both SiC and GaN devices is presented and an interesting experimental comparison among these two technologies will be given in terms of dynamic performances, electromagnetic compatibility, stability, efficiency, and so on.

During the last few years, single-stage power conversion systems has undergone a fast evolution to replace the conventional two-stage architecture, which includes a front-end dc-dc boost converter (BC) and an output voltage source inverter (VSI) [1]. This evolution has grown up to improve the overall system performance in terms of reducing its size, weight, and complexity. Most of these single-stage topologies and their different modulation schemes have been reviewed in [1]. Among these different single-stage options, the split-source inverter (SSI), shown in Figure 1, has been recently proposed in [2] as a single-stage dc-ac power converter topology to overcome some demerits in the other single-stage topologies, like the discontinuity of the input current and the dc-link voltage. According to [1], the SSI has the following merits: continuous dc-link voltage; continuous input current; lower switch voltage stresses with higher voltage gains, i.e. for lower input dc voltages, compared to the other equivalent topologies; lower passive component-count; no need for additional active switches compared to the standard VSI; same standard modulation schemes as the VSI for basic operation; same switching states as the VSI. Meanwhile, it suffers from the following demerits: higher current stresses of the lower switches; higher voltage stresses and higher THD of the output voltage for lower voltage gains, i.e. for higher input dc voltages; high frequency commutations of the input diodes. Several research works have been done on the SSI, as in [3]-[6], where the authors in [3]-[5] are discussing its three-level operation using the diode-clamped and flying capacitors bridges, while its single-phase operation is discussed in [6]. Meanwhile, its control scheme in grid-connected mode of operation has not been investigated yet. The SSI is modulated using the same eight standard states of the VSI, unlike the ZSI that utilizes an additional state, called the shoot-through state, to achieve the boosting capability. Such additional state gives an additional degree of freedom to control its dc side independently from the ac one, in which the two-stage conventional control method is utilized. Hence, it is of paramount importance to investigate the possibility of using the conventional synchronous reference frame control technique, that is commonly used with the two-stage architecture, with the so-called SSI, which is convenient for many applications. Accordingly, this paper models the SSI dc side and proposes a modified modulation scheme combined with the synchronous reference frame control technique, which is shown in Figure 2, to achieve a decoupled control scheme of the SSI in grid-connected mode, i.e. the dc and the ac sides of the SSI can be controlled independently. In this decoupled control scheme, the common mode term of the ac modulating signals is used to regulate the dc side, leading to an additional degree of freedom of having two control parameters like the two-stage architecture.

In this paper, we present an experimental comparison of two LiDAR systems, employing the SiPM and the APD as photodetectors, in terms of TOF measurements differing for the distance of the target and at different intensities of ambient light. The use of the APD represents the conventional approach, while the implementation of the SiPM is innovative. The performed measurements achieved very promising results, thus demonstrating the effectiveness of our LiDAR based on SiPM.

The extraction of biomedical parameters, for early disease detection, is assuming today an ever increasing and fundamental importance. In particular, in the cardiologic field, the preejection period (PEP) is the duration of the iso-volumetric left ventricle contraction until the aortic valve opening. This parameter is a non-constant additive delay, which rapidly changes in response to stress, emotion and physical effort. To estimate this period, several wearable electronics devices have been developed in literature, and among them the Impedance Cardiogram equipment is the most used. However, these systems are often expensive and bulky. In this paper, we propose a cost-effective and easy to employ ECG+PPG combo system able to measure pre-ejection period in a cardiac cycle. The employed system is composed of an ECG acquisition board able to host two PPG probes too.

In this paper, we measure the main photoelectrical parameters of Dye Sensitized Solar Cells (DSSCs) based on ruthenium complexes at different irradiance levels, incident wavelengths, temperatures and hours of light soaking

In this paper, we present an innovative way to measure some physiological parameters (such as the pre-ejection period, the pulse transit time, the blood pressure) in a cardiac cycle. A combo PPG-ECG system has been developed and employed to extract both the ECG signal from standard limb leads and simultaneously the photoplethysmography signal from the wrist and the forearm, to calculate the pre-ejection period. This system represents an easy and non-invasive technique to determine these biomedical parameters without using expensive impedance cardiography equipment.

In this paper, we measure the main photoelectrical parameters of Dye Sensitized Solar Cells (DSSCs) based on ruthenium complexes at different irradiance levels, incident wavelengths, temperatures and hours of light soaking.

This paper deals with a novel class of optical sensors for ethanol vapor, based on polystyrene opals infiltrated with a hydrogel sensitive to ethanol. Optical characterization of such opals has been performed, proving their effectiveness as sensors

In this paper, the authors, present last results on a low cost method to monitoring Passive-Optical-Network, which it uses Fiber-Bragg-Gratings and a modified Optical-Time-Domain-Reflectometer, and a remote power supply of Optical-Network-Terminals by a bivalent-use cable.