The application of a low-complexity current generator circuit and multisine signals for Electrochemical Impedance Spectroscopy (EIS) of Li-Ion batteries is presented. The proposed system is comprised of a Howland current pump driven by a general-purpose multifunction DAQ, which provides the excitation signal and acquires current and voltage waveforms from the battery under test. The presented results show that the proposed system can provide comparable results with respect to a reference instrument and potentially obtain a reduction in measurement time with respect to a single sine excitation method.

High resolution Digital-to-Analog Converters (DACs) are known to be characterized by static testing procedures with a remarkable duration, due to the huge number of employed codes. This paper proposes a method that allows to reconstruct the Integral Non-Linearity through the Compressed Sensing, by measuring the DAC output on a reduced number of codes. The proposed reduced-code test is evaluated for several compression ratios, turning out well performing in terms of Root Mean Square Error.

This work is focused on the arc faults phenomenon in DC photovoltaic (PV) systems. The paper gives an overview of arc detection methods proposed in literature and presents a preliminary experimental characterization of the arcing current, focusing the attention on series arcs, whose detection is particularly challenging. Experimental tests are carried out, both in laboratory and on field, in order to investigate some relevant characteristics in the arcing current, which can be feasible for the arc detection purpose. Both arcing and non-arcing current signals are acquired and compared in both time and frequency domain. On-field measurements are carried out on a real photovoltaic system, in accordance with the tests requirements of UL 1699B Standard for protection devices against arc faults.

Nowadays great interest is placed on the environmental issue. Greenhouse gas emissions are more than 50 % higher than in 1990. European energy policy has been supporting efficient energy management in order to reduce the railway transport emissions by 50 % within 2030. The railway stakeholders are encouraged to adopt technological solutions to foster energy efficiency. The electrodynamic braking combined with the adoption of reversible substations is one of the most promising solutions. In order to evaluate the impact of this innovative technology, a measurement campaign has been conducted on Metro de Madrid where a reversible substation was installed. In this paper, a preliminary analysis on the data acquired is presented. Traceable and accurate on-board train measurements of the energy flows and the losses are fundamental to quantify the impact of these new technologies and to carry out a survey on the efficiencies of the different vehicle components and on the strategies to reduce the energy consumption in the various operation modes.

The liberalization of the railway market and the aim of fostering the interoperability among European countries makes the monitoring of the quality of the power (PQ) exchanged between trains and supply system even more important. At the moment, definitions, procedures and techniques for DC railway systems are under development. In this contest, the paper proposes a reference generation system able to reproduce the voltage and current waveforms experienced at pantograph by a DC 3 kV locomotive. The system is able to generate simultaneously voltage and current signals up to 10 kV peak and 1.2 kA peak respectively. The AC ripple which can be superimposed has a bandwidth of 30 kHz for the voltage and 600 Hz for the current. Moreover, it is able to reproduce several PQ events both with an accuracy, in the worst case of 1 %.