Search results for " Macchine E Azionamenti Elettrici"
showing 10 items of 466 documents
Design and simulation of a fast DC recharging station for EV
2017
In this paper a detailed description of the design and simulation of a DC ultra-fast recharging station for Electric Vehicles is carried out. The system consist of a single AC/DC grid connected inverter, a DC-Bus and two DC/DC converter to recharge the batteries of the EVs. The system also has the vehicleto- grid (V2G) capability. The design of the components of the system and the control schemes are explained and a simulation of the system, performed in Matlab/Simulink environment is presented.
Nexus Water & Energy: A Case Study of Wave Energy Converters (WECs) to Desalination Applications in Sicily
2016
The recent studies about interactions among energy and water are considered as a new field of research. As almost all energy generation processes require significant amounts of water, and water requires energy for treatment and transport, so these two resources are inextricably linked. The main aim of this work is a presentation of the use of renewable energy for desalination plants in Sicily: in particular exploitation of wave energy into electrical energy necessary for water treatment. Desalination is the most energy intensive water treatment technology but it could be solution for many problems in water supply for areas with chronic debt of water. In this study we find three section: in …
Leading the way toward fuel parity in photovoltaics: The utility-scale market in Sicily, Italy
2016
The global photovoltaic (PV) market has been growing exponentially since almost twenty years. This huge demand for photovoltaic systems has been mainly driven by public subsidies in the form of a variet y of national incentive schemes. However, in Countries where successful incentive schemes have been pioneered and are now – as planned - being brought to an end, the PV market is called to the challenge of surviving without any incentive to the end user. Grid and fuel-parity represent the keystone of this emerging new phase in the history of this renewable energy technology. In this paper we present a sensitivity analysis showing that in Sicily, Italy, the Levelized Cost of Energy from utili…
Dead-time impact on the harmonic distortion and conversion efficiency in a three-phase five-level Cascaded H-Bridge inverter: mathematical formulatio…
2023
To avoid leg short-circuit in inverters, dead time must be introduced on leg gate signals. Dead time affects the inverter output voltage fundamental harmonic amplitude, voltage harmonic distortion and inverter efficiency by introducing additional voltage drops. In this regard, dead time effects have been widely investigated for traditional two-level three-phase voltage source inverters in the literature but not extensively for multilevel topology structures. This paper provides a detailed analysis of dead time impact on the harmonic distortion and efficiency of Cascaded H-Bridges Multilevel Inverters (CHBMIs). For this purpose, a general mathematical formulation to determine voltage drop du…
Minimization of detent force in a 1 kW linear permanent magnet generator for the conversion of sea waves energy: Numerical and experimental validation
2015
Linear permanent magnet generators are widely considered for the direct conversion of energy contained in sea waves [1-3]. Both planar and tubular structures have been proposed [4-6] and all these structures present several advantages: relative high efficiency, simplicity of the structures, high sturdiness. However, as all other linear machines they present some drawbacks: oscillations in the movement, distortion in the generated electromotive force (emf), etc. In this paper we focus our attention on the parasitic oscillations of the translator which are caused by the presence of a high detent force. Detent force is generated by the fact that magnetic energy presents a minimum when the leng…
High-Speed Machines: Typologies, Standards, and Operation under PWM Supply
2018
This paper presents an overview of the most recent state of the art in the field of high-speed electric machines fed through high-frequency converters. This type of systems is rapidly wide spreading in aeronautical and automotive applications, as well as microturbines. Each typology has its own advantages and downsides, which are analytically presented in this paper. Some types of high-speed electric machines require high-frequency voltage supply, highly stressing the dielectric materials of the winding insulation system. For this reason, in high-speed electric drives, premature failure may occur and a reduction of the total system reliability has been observed in the past years. Such issue…
Rainfall energy harvester
2015
This chapter provides a detailed study on the harvest of the energy contained in raindrops by means of piezoelectric transducers. The energy harvester has the role of an electric source, able to recharge storage devices of small electronic components, such wireless sensors, by using the vibrational energy released by the drops hitting the transducer, reducing in such a way the chemical waste of conventional batteries. In technical literature, diverse studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, also to limit optimistic forecast…
Incidence of PV module rated power tolerances on PV system energy production
2016
Discussing the electrical energy production of a PV system realized by PV modules with a large range of tolerance for the rated power values is the aim of this paper. In particular, the paper shows how the incidence of tolerance can be significant, in terms of output power reduction, when the PV system works in partial shading condition. For this issue, using a tool developed for this purpose, several simulations have been run, which consider different tolerance values for the module rated power and different shading patterns for the PV array. The authors quantify the peak power values of the different system configurations, showing the importance of the choice of modules with reduced toler…
Hydrogen Supplied Wireless Charging System for Electric Vehicles
2020
The aim of this work is the experimental characterization of a Wireless Charging System based on IPT (Inductive Power Transfer) supplied by a PEMFC (Proton Exchange Membrane Fuel Cell) in order to verify the possibility of its installation in not electrified areas. A hydrogen-based supply system is designed and assembled with the purpose of having an EV (electrical vehicle) charging station not connected to the main power grid. An efficiency analysis of the wireless transmission system is carried out taking into account external parameters such as distance and misalignment between the transmitter coil and the receiver coil, verifying the integration potentialities of both IPT and fuel cell …
Effects of post-filtering in grid-synchronization algorithms under grid faults
2018
Abstract The spread of distributed generation systems has reinforced concerns and requirements on grid-tied power converters. The synchronization with the utility voltage vector is a major concern. In the literature, algorithms based on Phase Locked Loops are extensively presented. In spite of adequate performances under ideal and balanced grid conditions, under grid faults great inaccuracies arise. Shortcomings are overcome by advanced algorithms at the expenses of the complexity and computational cost. In this paper, grid synchronization algorithms are addressed. A solution is proposed by introducing a new post-filter stage in a Decoupled Double Synchronous Reference Frame not affecting, …