Search results for "Tito"
showing 10 items of 719 documents
Experimental Implementation of an Enhanced Field Oriented Control Strategy for Induction Motors Using a Low-Cost ATSAM3X8E Microcontroller
2020
This paper presents a low-cost Micro Controller Unit (MCU) implementation of an enhanced Field Oriented Control (FOC) technique that takes into account the non-linearity of the ferromagnetic material. The algorithm is applied to a three-phase 5.5 kW Induction Motor (IM) and experimentally carried out by means of an ATMEL ATSAM3X8E microcontroller. The effectiveness of the enhanced control strategy is verified by comparing the dynamic performances of the electric drive with those obtained by means of a traditional FOC technique. For this purpose, an experimental test bench is set up for the implementation of the enhanced FOC technique. Finally, the technical and economic features of the simp…
Interior Permanent Magnet Synchronous Machine Drive Powered by Fuel Cell for Automotive Applications
2020
Electric vehicles represent an optimal solution for the reduction of pollution in urban areas. In particular, the Fuel Cell (FC) technology is a promising solution especially for its charging times and zero CO2 direct emissions. The paper addresses the design and performance study of an Interior Permanent Magnet Synchronous Machine (IPMSM) drive powered by fuel cell for automotive applications. The IPMSM drive is powered by the use of 5,5 kW FC unit and it is composed of two DC-DC power converters and one inverter. In detail, a test bench has been carried out for the evaluation of the performances of each IPMSM drive conversion stage. Moreover, in order to simulate automotive working condit…
Influence of drying to the structure of lactitol monohydrate
1997
The purpose of this study is to find out the effect of the crystal water content on the crystal structure of lactitol monohydrate. Crystal water was removed by drying over silicagel at 40°C and by using phosphorus pentoxide as drying agent at 20°C. The amouts of water removals were identified by thermogravimetry, the melting points and the heat of fusions were calculated from the results of differential scanning calorimetry measurements and the structure of samples were identified by X-ray powder diffraction method. Over 23 w/w% of total water content could removed by gently drying until significant structural changes could be detected. The melting point of anhydrous lactitol obtained by dr…
Implementation on NI-SOM sbRIO-9651 and Experimental Validation of Multi-Carrier PWM Techniques for Three-Phase Five Level Cascaded H-Bridge Inverter
2021
Multilevel Power Inverters (MPIs) represent a valid solution to improve the performances of energy production systems from renewable energy sources. Furthermore, the use of novel FPGA control systems allows simplifying the implementation of multicarrier PWM techniques for MPIs with computational benefits. This paper describes the implementation of several multicarrier PWM techniques on NI-SOM sbRIO-9651 for the control of a three-phase five-level cascaded H-bridge inverter. In detail, sbRIO-9651 is a control system in the field of Power Electronics and Drives (PED) programmable in the LabVIEW graphical programming environment. The paper is focused on modulation techniques implementation, te…
Recens. a: Tito Livio Frulovisi, Hunfreidos, a cura di C. Cocco, Firenze, SISMEL-Edizioni del Galluzzo, 2014, in «Bollettino di Studi Latini» 46,1 (2…
2016
Recensione alla prima edizione dell'Hunfreidos di Tito Livio Frulovisi, poemetto epico-encomiastico scritto nel 1436 in onore del duca Humphrey di Gloucester, fratello di re Enrico V d'Inghilterra. L'edizione è stata curata da Cristina Cocco, dell'Università di Cagliari, ed è apparsa nel 2014, pubblicata dalla SISMEL-Edizioni del Galluzzo di Firenze.
L’«archivio della memoria» tra 'biografia' e ‘diario’
2018
Donatella La Monaca si inoltra nell’intrinseco rapporto tra la scrittura epistolare, saggistica ed inventiva di Tomasi di Lampedusa soffermandosi sulle modalità con cui l’invenzione e il ricordo si fondono nell’azione trasfigurante della memoria, nel suo valore cognitivo e poetico. Ci si spinge da ultimo a ricostruire i termini di un dibattito sul caso Gattopardo di cui si pongono in risalto alcuni snodi cruciali tra cui quello, che, proprio nel contesto di tale dibattito, approfondisce le fasi evolutive di un suo episodio nevralgico, ovvero la lettura, animata da tensioni etiche e civili, di Leonardo Sciascia,dall’iniziale diffidenza alla matura comprensione.Si compone così un itinerario c…
The role of the effect of manufacturing tolerances on a tubular linear ferrite motor
2015
Electric machines are often designed without considering workmanship and materials tolerances. Their manufacturing process involves a series of steps, starting with raw materials and ending with the machine assembly. In each of these steps occur deviations due, for instance, to mistakes in positioning tools or to the tolerances in the electrical and magnetic characteristics of the materials. These deviations may cause unwanted parasitic effects such as torque ripple, losses or acoustic noise. Such effects have to be considered especially in machines used in industrial drives for high performance applications. Moreover the tolerances in the magnetic materials have a considerable effect on th…
Mathematical formulation of pulse amplitude modulation selective harmonic elimination in multilevel three phase inverters
2022
In this paper multilevel cascaded H-bridges (CHB) three phase inverters with 2n dc sources, n=1,2,3,... are considered and a mathematical formulation providing both 2n switching angles and dc voltage source to eliminate n+1 harmonics and their respective multiple from their output voltage waveform, is proposed. The computed angles don't depend on modulation index and the source voltages linearly vary with it. The proposed procedure finds the solution through an analytical formula that avoids to solve transcendental systems and presents very low computational cost. A lot of low order harmonics are eliminated, returning a very low total harmonic distortion (THD). Particularly for 9-level conf…
Experimental Comparative Analysis of Efficiency and THD for a Three-phase Five-level Cascaded H-Bridge Inverter Controlled by Several MC-PWM Schemes
2021
Cascaded H-Bridges Multilevel Inverters are an innovative and promising solution in different application fields. This topology allows obtaining an improvement in the performance (e.g. reduced harmonic content, the low voltage stress on power components, and high efficiency) in respect to the traditional two-level inverters. In this context, the Multicarrier-PWM strategies play an important role thanks to their features. This paper presents an experimental investigation on the performance of a three-phase five-level Cascaded H-Bridge inverter by using different PWM modulation strategies. In particular, the paper is focused on the experimental validation of the main features of Multicarrier …
French firms’ strategies for protecting their intellectual property
2012
In attempting to protect their innovations, firms can choose from a range of mechanisms, which may be either non-statutory (trade secrets, design complexity, and lead-time advantage over competitors) or statutory (patent, design registration, trademark, copyright). Yet, little is known about how firms do actually make their choices from among these different appropriability mechanisms. The aim of this paper is to determine how French firms’ use of intellectual property protection mechanisms relates to the type of innovation, the characteristics of the market sector in which they operate, the firms’ characteristics, and their human resources strategies. Our empirical model draws on four Fren…