Search results for "Stator"
showing 10 items of 123 documents
Questioni cronologico-attributive e tecnica compositiva del «Carmen de Hastingae proelio» di Guy d’Amiens
2018
In questo studio il «Carmen de Hastingae proelio» assegnato a Guy d’Amiens viene sottoposto a una lunga disamina, con la rassegna delle principali questioni cronologiche e attributive susseguitesi dalla prima metà dell’Ottocento fino ai nostri giorni, l’analisi e la discussione dei più rilevanti problemi storico-letterari e interpretativi e, nella seconda e più ampia parte, l’esame di tre passi del poemetto a loro modo altamente significativi (il proemio, la geste di Taillefer e l’incoronazione di Guglielmo il Conquistatore). Tale disamina mira, in primo luogo, a rimettere in discussione un’impostazione e un livello di lettura dell’opera vòlti, in maniera preponderante se non esclusiva, a …
A Saturation Model of the Synchronous Reluctance Motor and its Identification by Genetic Algorithms
2018
This paper proposes a complete saturation model of the Synchronous Reluctance Motor (Syn1231), accounting for both the self-saturation and cross-saturation effects. This model is based on an analytical relationship between the stator flux and current components, and is characterized by parameters presenting an interesting physical interpretation, differently from many other saturation model in the scientific literature. It proposes also an identification technique of such a model based on stand-still tests, without the need of locking the rotor. The proposed saturation model permits the complete description of the magnetic behaviour of the machine with 8 parameters, fewer than those require…
Extended complex Kalman filter for sensorless control of an induction motor
2014
Abstract This paper deals with the design of an extended complex Kalman filter (ECKF) for estimating the state of an induction motor (IM) model, and for sensorless control of systems employing this type of motor as an actuator. A complex-valued model is adopted that simultaneously allows a simpler observability analysis of the system and a more effective state estimation. The observability analysis of this model is first performed by assuming that a third order ECKF has to be designed, by neglecting the mechanical equation of the IM model, which is a valid hypothesis when the motor is operated at constant rotor speed. It is shown that this analysis is more effective and easier than the one …
Evaluation of the power quality from a seawave power farm for different interconnection schemes
2007
In this paper we present an approach to the interconnection of a seawave power farm to the grid The generator type used in the farm is a Permanent Magnet (PM) linear generator driven from the seawaves that generates, therefore, highly distorted emfs. We propose and compare two possible ways to interconnect the farm to the grid. One is based on an approach where for each generator there is a conversion subsystem that permits the direct connection of each generator to the a.c. network, the other one is based on an ac.-d.c. converter that is connected to the generator, the converter is connected to a dc link that can receive the power from every unit and that can supply a dc-ac converter direc…
Solid rotor induction machines for use in electrically-assisted turbochargers
2006
The stator leakage reactance has a major influence on the performance of a solid rotor induction machine. It is larger and it is more difficult to define and calculate than in a cage-rotor machine. When the higher leakage reactance is taken into account, the equivalent circuit model gives predictions of sufficient precision for design purposes. The airgap, normally chosen to be quite small, is preferably quite large by general standards. The torque varies as (V/f) 3 which makes it difficult to provide a wide range of constant power operation in a variable speed application. Slitting the rotor helps to improve the characteristic for variable-speed duties.
A new solution for the sea wave exploitation. A linear ironless generator
2019
The exploitation of sea wave represents an important frontier for the energy sustainability in the next future. Despite the proposal of several techniques and solutions, commercial devices are not available. In this context, the Department of Engineering is investigating an innovative solution based on linear energy generators. This machine can be adopted as the main component in a wave energy converter, that is the device for the energy extraction of sea wave. Starting from an existing prototype, the paper examines the replacement of the iron stator with a non-magnetic material, in order to solve several common problems of linear generators, such as the cogging force. Results are reported,…
Design and Low-Cost Implementation of an Optimally Robust Reduced-Order Rotor Flux Observer for Induction Motor Control
2007
The aim of this paper is to design and analyze reduced-order observers of the rotor flux of induction motors. The design is carried out in two steps. In the first step, a boundary of the stability region of the observation error is obtained corresponding to a chosen Lyapunov function. In the second step, the boundary is translated into a performance index that is minimized with respect to stator and rotor resistance variations and differences of voltages supplying the motor and those supplying the observer in order to obtain the largest stability region. Implementation of the observer on a low-cost fixed-point digital signal processor using look-up tables is described. Experimental results …
A nonlinear observer for rotor flux estimation considering magnetic saturation effects in induction motor drives
2015
This paper proposes a non-linear observer for In- duction Machine (IM) drives which takes into consideration the saturation effects. The non-linear observer is based on an original formulation of the dynamic model of the IM taking into consideration the magnetic saturation of the iron core. A Lyapunov based convergence analysis is proposed in order to suitably compute the observer gain guaranteeing the stability of the observer. The proposed non-linear observer has been tested in numerical simulation and experimentally on a suitably developed test set-up. Its behaviour has been compared to that obtained with a classic Full-Order Luenberger Observer (FOLO) in variable flux working conditions…
Salt content impacts food preferences and intake among children
2012
This work was supported by a PhD grant from the Nutrition, Chemical Food Safety and Consumer Behavior Division of INRA (French National Institute for Agronomical Research, France) and the Regional Council of Burgundy (France) received by SB; and by a research grant (Gustolf) from Regional Council of Burgundy (France) received by SN. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.; Decreasing dietary sodium intake, which can be achieved by reducing salt content in food, is recommended. Salt contributes to the taste of foods and makes them more enjoyable. Whether a food is liked or disliked is an important determina…
Peripheral, central and behavioral responses to the cuticular pheromone bouquet in Drosophila melanogaster males.
2011
International audience; Pheromonal communication is crucial with regard to mate choice in many animals including insects. Drosophila melanogaster flies produce a pheromonal bouquet with many cuticular hydrocarbons some of which diverge between the sexes and differently affect male courtship behavior. Cuticular pheromones have a relatively high weight and are thought to be -- mostly but not only -- detected by gustatory contact. However, the response of the peripheral and central gustatory systems to these substances remains poorly explored. We measured the effect induced by pheromonal cuticular mixtures on (i) the electrophysiological response of peripheral gustatory receptor neurons, (ii) …