Search results for "Stator"
showing 10 items of 123 documents
On the Detection of Distributed Roughness on Ball Bearings Via Stator Current Energy: Experimental Results
2009
S1/3 The stator stalk of Escherichia coli ATP synthase
2008
Neatņemamās daļas tiesīgie un to atstumšana no mantojuma
2016
Neatņemamā daļa, neatņemamās daļas tiesīgie un to atstumšana- šie tiesību institūti Latvijas Republikas Civillikumā regulēti ir diezgan sarežģīti. Svarīgi ir saprast šo institūtu nozīmi un vēsturisko attīstību. Šī iemesla dēļ tika apkopota pieejamā literatūra, tiesu prakse un ārvalstu tiesību normas par šo tematu.Darba mērķis ir identificēt problēmjautājumus saistībā ar šiem institūtiem, kā arī piedāvāt labojumus vai papildinājumus Latvijas Republikas Civillikumā, lai tas būtu vieglāk pieņemams Latvijas sabiedrībai, un cilvēkiem, kuri nav apmācīti juristi, nerastos nevajadzīgi pārpratumi un strīdi.Šo institūtu mērķis ir noteikt tiesības testatora tuvākajiem radiniekiem, kas ir neatņemamās d…
Notes per a un exemplar de La conquesta de València (València, Diego de Gumiel, 1515)
2008
En aquest treball s’ofereix una descripció de l’exemplar de l’Aureum opus regalium privilegiorum civitatis et Regni Valentiae cum historia cristianissimi Regis Iacobi ipsius primi conquistatoris conservat a la Casa del Libro (San Juan, Puerto Rico), una de les darreres aventures editorials de l’impressor Diego de Gumiel (30 d’octubre de 1515).
Oro-gustatory perception of dietary lipids and calcium signaling in taste bud cells are altered in nutritionally obesity-prone Psammomys obesus.
2013
Since the increasing prevalence of obesity is one of the major health problems of the modern era, understanding the mechanisms of oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. We have conducted the present study on Psammomys obesus, the rodent desert gerbil which is a unique polygenic natural animal model of obesity. Our results show that obese animals exhibit a strong preference for lipid solutions in a two-bottle test. Interestingly, the expression of CD36, a lipido-receptor, in taste buds cells (TBC), isolated from circumvallate papillae, was decreased at mRNA level, but remained unaltered at protein level, in obese animals. We further st…
Tuning of Extended Kalman Filters for Sensorless Motion Control with Induction Motor
2019
This work deals with the tuning of an Extended Kalman Filter for sensorless control of induction motors for electrical traction in automotive. Assuming that the parameters of the induction motor-load model are known, Genetic Algorithms are used for obtaining the system noise covariance matrix, considering the measurement noise covariance matrix equal to the identity matrix. It is shown that only stator currents have to be acquired for reaching this objective, which is easy to accomplish using Hall-effect transducers. In fact, the Genetic Algorithm minimizes, with respect to the system covariance matrix, a suitable measure of the displacement between the stator currents experimentally acquir…
Validation of a New Method for the Diagnosis of Rotor bar Failures via Wavelet Transformation in Industrial Induction Machines
2006
[EN] In this paper, the authors propose a method for the diagnosis of rotor bar failures in induction machines, based on the analysis of the stator current during the startup using the discrete wavelet transform (DWT). Unlike other approaches, the study of the high-order wavelet signals resulting from the decomposition is the core of the proposed method. After an introduction of the physical and mathematical bases of the method, a description of the proposed approach is given; for this purpose, a numerical model of induction machine is used in such a way that the effects of a bar breakage can clearly be shown, avoiding the influence of other phenomena not related with the fault. Afterward, …
The Use of the Wavelet Approximation Signal as a Tool for the Diagnosis of Rotor Bar Failures
2005
[EN] The aim of this paper is to present a new approach for rotor bar failure diagnosis in induction machines. The method focuses on the study of an approximation signal resulting from the wavelet decomposition of the startup stator current. The presence of the left sideband harmonic is used as evidence of the rotor failure in most diagnosis methods based on the analysis of the stator current. Thus, a detailed description of the evolution of the left sideband harmonic during the startup transient is given in this paper; for this purpose, a method for calculating the evolution of the left sideband during the startup is developed, and its results are physically explained. This paper also show…
An Analytical Comparison between DWT and Hilbert-Huang-Based Methods for the Diagnosis of Rotor Asymmetries in Induction Machines
2007
In the paper two alternative tools are applied and compared in order to diagnose the presence of rotor asymmetries in induction machines. Both tools are applied to the stator startup current. The objective is to extract the evolution during the startup transient of the left sideband harmonic associated with the asymmetry, which constitutes a reliable evidence of the presence of the fault. The first tool is the discrete wavelet transform (DWT) and its validity for the diagnosis was proven by the authors in previous works, even in cases where the classical Fourier approach does not lead to correct results. Despite its good results, some constraints remained, such as the selection of an optima…
A general procedure for the construction of Gorges polygons for multi-phase windings of electrical machines
2018
This paper presents a simple and effective procedure for the determination of the Gorges polygon, suitable for all possible winding configurations in electrical machines. This methodology takes into account the determination of a Winding Distribution Table (WDT), in which all the information about the distribution of the currents along the stator periphery is computed and from which the Görges polygon are easily derived. The proposed method can be applied to both symmetrical and asymmetrical multi-phase windings, including concentrated, fractional, reduced and dead-coil ones. The examples provided in this paper demonstrate the versatility of the proposed method.