Search results for "Induction"

Experimental investigation on high-efficiency control algorithms for three-phase induction motors

2020

This paper presents an experimental investigation regarding the power losses variations occurring in three-phase induction motors (IMs) as a function of the magnetization level of the machine. More in detail, the power losses identification is obtained by changing in real-time the working operating conditions of the IM drive and the IM reference flux. The sets of measurements are carried out by setting up a test bench and the obtained results confirm that the power losses occurring in induction motors can be minimized by adequately setting the direct axis current component for each IM working condition. This research represents the starting point for the conception of advanced real-time los…

Advanced Motion Control in Induction Motor Systems - Modelling, Analysis and Control

Using a unified notation, this thesis collects and discusses the most important steps and issues in the design of estimation and control algorithms for induction motors. It contains many estimation and control algorithms. Their stability is analyzed and their performance is illustrated by simulations and experiments on the same induction motor. An intense and challenging collective research effort is carefully documented and analyzed, with the aim of providing and clarifying the basic intuition and tools required in the analysis and design of nonlinear feedback control algorithms. This material should be of specific interest to engineers who are engaged in the design of control algorithms f…

MRAS Sensorless Techniques for High Performance Linear Induction Motor Drives.

2010

This paper proposes an MRAS (Model reference Adaptive System) speed observer suited for linear induction motors (LIM). Starting from the dynamical equation of the LIM in the synchronous reference frame in literature, the so-called voltage and current models of the LIM in the stationary reference frame, taking into consideration the end effects, have been deduced. These equations have been used respectively as reference and adaptive model of an MRAS observer. As machine under test, a complete dynamic model, based on the constructive elements of the LIM and taking into consideration the end effects by the definition of a proper air-gap function, has been adopted. This model has been previousl…

Innovative Observers for Induction Motor Control

In this thesis the problem of designing observers and controllers for induction motors has been studied and thoroughly discussed using tools from the nonlinear system theory, both for analysis and control purposes. Useful techniques have been used to identify the machine parameters off-line. In the Introduction was dealt the design a control system for a drive of asynchronous machines that uses a voltage source inverter to generate the currents and voltages which carry the drive by making use of an observer of the state rotor variables. The used control algorithms is the \textit{field oriented control} (FOC). The model of the asynchronous induction motor is described starting from the mecha…

Extracting Structured Knowledge From Sensor Data for Hybrid Simulation

2014

Obtaining continuous and detailed monitoring of indoor environments has today become viable, also thanks to the widespread availability of effective and flexible sensing technology; this paves the way for the design of practical Ambient Intelligence systems, and for their actual deployment in real-life contexts, which require advanced functionalities, such as for instance the automatic discovery of the activities carried on by users. Novel issues arise in this context; on one hand, it is important to reliably model the phenomena under observation even though, to this end, it is often necessary to craft a carefully designed prototype in order to test and fine-tune the theoretical models.

A Structural Approach to Infer Recurrent Relations in Data

2014

Extracting knowledge from a great amount of collected data has been a key problem in Artificial Intelligence during the last decades. In this context, the word "knowledge" refers to the non trivial new relations not easily deducible from the observation of the data. Several approaches have been used to accomplish this task, ranging from statistical to structural methods, often heavily dependent on the particular problem of interest. In this work we propose a system for knowledge extraction that exploits the power of an ontology approach. Ontology is used to describe, organise and discover new knowledge. To show the effectiveness of our system in extracting and generalising the knowledge emb…

Pre-convenzioni: un frammento dello Sfondo

2014

In this paper I argue that there exist conventions of a peculiar sort, which are neither norms nor regularities of behaviour, partaking of both. I proceed as follows. After a sketchy analysis of the meaning of ‘convention’, I give some examples of the kind of phenomena I have in mind: bodily skills, know-how, taste and style, habitus (P. Bourdieu), «disciplines» (M. Foucault). Then I group some arguments supporting my claim: (i) considerations about the identity conditions of precedents (D. Lewis) and about the projectibility of predicates in inductive inference generally (N. Goodman); (ii) thoughts about rule-following (L. Wittgenstein); (iii) an examination of some of J. R. Searle’s ideas…

Pre-conventions. A fragment of the Background

2016

In this paper I argue that there exist conventions of a peculiar sort which are neither norms nor regularities of behaviour, partaking of both. I proceed as follows. After a brief analysis of the meaning of ‘convention’, I give some examples of the kind of phenomena I have in mind: bodily skills, know-how, taste and style, habitus (P. Bourdieu), “disciplines” (M. Foucault). Then I group some arguments supporting my claim: (i) considerations about the identity conditions of precedents (D. Lewis) and about the projectibility of predicates in inductive inference generally (N. Goodman); (ii) thoughts about rule-following (L. Wittgenstein); (iii) an examination of some of J. R. Searle’s ideas ab…

Preconvenciones: un fragmento del Trasfondo

2016

Abstract, In this paper I argue that there exist conventions of a peculiar sort, which are neither norms nor regularities of behaviour, partaking of both. I proceed as follows. After a sketchy analysis of the meaning of ‘convention’, I give some examples of the kind of phenomena I have in mind: bodily skills, know-how, taste and style, habitus (P. Bourdieu), “disciplines” (M. Foucault). Then I group some arguments supporting my claim: (i) considerations about the identity conditions of precedents (D. Lewis) and about the projectibility of predicates in inductive inference generally (N. Goodman); (ii) thoughts about rule-following (L. Wittgenstein); (iii) an examination of some of J. R. Sear…

Online Fault Diagnosis System for Electric Powertrains Using Advanced Signal Processing and Machine Learning

2018

Online condition monitoring and fault diagnosis systems are necessary to prevent unexpected downtimes in critical electric powertrains. The machine learning algorithms provide a better way to diagnose faults in complex cases, such as mixed faults and/or in variable speed conditions. Most of studies focus on training phases of the machine learning algorithms, but the development of the trained machine learning algorithms for an online diagnosis system is not detailed. In this study, a complete procedure of training and implementation of an online fault diagnosis system is presented and discussed. Aspects of the development of an online fault diagnosis based on machine learning algorithms are…