Search results for " drive"
showing 10 items of 286 documents
Practical Implementation of a Synchronous PWM Strategy for Low Switching Frequency FOC of im Drives with ATSAM3X8E Microcontroller
2021
This paper presents a practical implementation of synchronous PWM modulation algorithm for an induction motor field oriented control powered by a DC/AC inverter and implemented on a low-cost microcontroller, the ATSAM3X8E. In particular, a simple algorithm, capable to calculate automatically an optimized set of frequency modulation indexes will be presented. Hysteresis bands are also introduced in the algorithm in order to avoid multiple changeovers during modulation index transitions. Experimental tests and their results will be shown and discussed, highlighting the benefits of the present algorithm, such as reduction of current harmonic content, reduction of current ripple and, consequent…
Diagnostics of stator winding failures in wind turbine pitch motors using Vold-Kalman filter
2019
Pitch systems are among the most failure-prone components in wind turbines. Winding failures in pitch motors are common due to high start-up loads and poor ventilation. This article presents a diagnostics scheme that can detect the stator winding failures in the pitch motors under time-varying speed and load conditions. The proposed approach based on three-phase motor currents can be directly integrated into the motor drive and can be used for induction as well as permanent magnet synchronous machines. The extended Park's vector calculated on the motor currents is order tracked based on the supply frequency from the drive using Vold-Kalman filter. The approach is shown to be robust under ar…
La cultura ci salverà? Processi di touristification a base culturale nel centro storico di Palermo
2023
Negli ultimi tre decenni la cultura ha avuto un ruolo chiave nella costruzione delle politiche urbane, divenendo uno strumento decisivo nella definizione delle strategie di sviluppo economico e nell’accesso alla competizione globale che caratterizzano l’attuale regime di neoliberismo urbano (Miles e Paddison 2005). Anche nel sud Europa la cosiddetta rigenerazione a base culturale ha rappresentato e continua ancora oggi a rappresentare una vera e propria ortodossia urbana, che trova nel turismo tanto una ragione di esistenza quanto un campo di attuazione. In particolare, negli ultimi anni i centri storici di molte città sudeuropee sono stati oggetto di trasformazioni profonde in cui pratiche…
Aspects Regarding the Modelling of Geometric and Strength Calculations of Worm Gears Using CAD Applications
2020
The new processes of plastic deformation of the gears eliminate some of the shortcomings of the old methods of their manufacture, while reducing the production costs and the time of production in series. This scientific paper addresses the issue of worm gears. The focus has been on geometric and strength calculations for this type of gear, using different CAD applications. The use of these applications substantially reduces the time before the actual development of the processing activities, as well as the early encounter of possible problems.
BaGaTel: an ontology driven database to ecodesign food products taking into account their nutritional and sensory qualities
2020
International audience
Relationship between cognitive and driving self-assessments in older drivers. Result of epidemiological and experimental on-road studies in france
2015
TRANSED 2015 - 14th International Conference on Mobility and Transport for Elderly and Disabled Persons, LISBONNE, PORTUGAL, 28-/07/2015 - 31/07/2015; Most older drivers are able to efficiently self-regulate their own driving practices, that means reducing driving exposure and avoiding the most challenging driving conditions such as driving at night or in poor weather or at complex intersections. We hypothesized that this self-regulation might exist only if older drivers have accurate insight into their own age-related functional and cognitive decline. This study aims to evaluate how well self-estimation of cognitive ability of older corresponds to their actual driving performance, as asses…
Software architectures for cloud robotics : the 5 view Hyperactive Transaction Meta-Model (HTM5)
2015
Software development for cloud connected robotic systems is a complex software engineeringendeavour. These systems are often an amalgamation of one or more robotic platforms, standalonecomputers, mobile devices, server banks, virtual machines, cameras, network elements and ambientintelligence. An agent oriented approach represents robots and other auxiliary systems as agents inthe system.Software development for distributed and diverse systems like cloud robotic systems require specialsoftware modelling processes and tools. Model driven software development for such complexsystems will increase flexibility, reusability, cost effectiveness and overall quality of the end product.The proposed …
Towards low-energy-light-driven bistable photoswitches : ortho-fluoroaminoazobenzenes
2021
AbstractThermally stable photoswitches that are driven with low-energy light are rare, yet crucial for extending the applicability of photoresponsive molecules and materials towards, e.g., living systems. Combined ortho-fluorination and -amination couples high visible light absorptivity of o-aminoazobenzenes with the extraordinary bistability of o-fluoroazobenzenes. Herein, we report a library of easily accessible o-aminofluoroazobenzenes and establish structure–property relationships regarding spectral qualities, visible light isomerization efficiency and thermal stability of the cis-isomer with respect to the degree of o-substitution and choice of amino substituent. We rationalize the exp…
Hypotheses engineering : first essential steps of experiment-driven software development
2019
Recent studies have proposed the use of experiments to guide software development in order to build features that the user really wants. Some authors argue that this approach represents a new way to develop software that is different from the traditional requirement-driven one. In this position paper, we propose the discipline of Hypotheses Engineering in comparison to Requirements Engineering, highlighting the importance of proper handling hypotheses that guide experiments. We derive a set of practices within this discipline and present how the literature has tackled them up to now. Finally, we propose a set of research questions that could guide future work towards helping practitioners. …
Neural contribution to postactivation potentiation
2015
The current study was designed to investigate the contribution of neural factors to postactivation potentiation (PAP). Neuromuscular function (i.e. twitches, H-reflexes, motor evoked potentials, and voluntary isometric ballistic contractions) of 8 power-trained (POW) and 8 endurance-trained (END) athletes was recorded before and after a 8-second maximal isometric conditioning contraction (CC) to induce PAP, to elucidate discriminating neural factors in exploiting PAP that might arise from the former training background compared to the latter. After CC, twitch peak force and rate of force development were significantly increased, with higher potentiation in POW (29 ± 11% and 64 ± 24%) than E…