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Nomenclatura Unesco > (33) Ciencias Tecnológicas > (3306) Ingeniería y tecnología eléctricas > (3306.03) Motores eléctricos

Mostrando recursos 1 - 20 de 1,125

1. Diagnosis of dynamic systems does not necessarily require simulation - Andreas Malik; Peter Struss
We present a paradigmatic example of a feedback-controlled system: an electric motor with sensor and controller. Diagnosis of this system is performed based on a qualitative model that reflects deviations of parameters and behavior from a fixed reference state. The hypothesis that has been examined in this case study is that detection of behavior discrepancies does not necessarily require simulation of behavior, but can be done by checking (qualitative) states only. The qualitative models and the state-based diagnosis algorithm proved to establish a basis sufficient for fault detection and fault identification in the motor example. Some of the general preconditions...

2. Readhesion Control of Single-Inverter-Multiple-Motor AC Traction Drives for Electric Railways by Using Multirate Sampling Observer - Lilit Kovudhikulrungsri; Daisuke Tateishi; Takafumi Koseki
This paper proposes an effective way to realize fast readhesion control of single-inverter-multiple motor traction drives. To do this, multirate sampling observers are introduced to all axles in order to estimate precise speed and load torque at every sampling instant. The slip-slide is detected by using the amount of the load torque correction estimated from the multirate sampling observer, which is insensitive to the effect of slope. The performance of the proposed control scheme is verified by comparing with the conventional method.

3. Multilevel Inverters for Electric Vehicle Applications - Leon M. Tolbert
Abstract This paper presents multilevel inverters as an application for all-electric vehicle (EV) and hybrid-electric vehicle (HEV) motor drives. Diode-clamped inverters and cascaded H-bridge inverters, (1) can generate near-sinusoidal voltages with only fundamental frequency switching; (2) have almost no electromagnetic interference (EMI) and common-mode voltage; and (3) make an EV more accessible/safer and open wiring possible for most of an EV’s power system. This paper explores the benefits and discusses control schemes of the cascade inverter for use as an EV motor drive or a parallel HEV drive and the diode-clamped inverter as a series HEV motor drive. Analytical, simulated,...

4. Development of a three-phase three-level inverter for an electric vehicle - Xiaoming Li; Richard Duke; Simon Round
The development of variable speed AC induction motor drive systems for electric vehicles has been carried out at the University of Canterbury for more than 20 years. A three-phase three-level IGBT inverter has been developed for the University of Canterbury electric vehicle propulsion system. This paper deals with the three-phase three-level inverter switching device selection and inverter construction details. Experimental testing has been undertaken to examine the operating characteristics of the completed three-phase three-level inverter driving one of the electric vehicle motors. 1.

5. Reliability Estimation of Complex Technical Systems with Dependency Modelling: A Fuzzy Approach - Edwin Vijay Kumar; S. K. Chaturvedi
Complex technical systems may fail unexpectedly leading to process disruption and may bring a safety-hazard situation. The system failure is an outcome of failure dependency among subsystems where the degradation process of subsystems/components is random and uncertain process. Hence, reliability assessment of complex systems is of paramount importance. Quantitative reliability assessment needs failure data, which is scarce and/or not well-recorded, thus statistically inconsistent in process industry. Most often, in such industries, the reliability is expressed linguistically (like Good, OK, Bad, etc.,) rather than quantitatively. This paper proposes an approach for quantitative reliability estimation considering failure dependency among subsystems using fuzzy...

6. Wireless power transmission system for a Micro Aerial Vehicle - Eri Shimane; Alseny Diallo; Takashi Komaru; Kimiya Komurasak; Yoshihiro Arakawa
Wireless power transmission system for a Micro Aerial Vehicle using microwave has been studied. In a transmitter system a microwave beam was formed and steered from-9deg to +9deg. In a rectenna system, eight rectennas were arrayed and connected in parallel to drive an electric motor on an MAV model at the altitude of 80cm from the transmitter emitting 3.5W power in total. In a tracking system, two pairs of receiver patch antennas with a leaf pattern were set in rectangular coordinates to detect the position of the MAV while it is circling over the transmitter. 1.

7. $rec.titulo
The reliability and performance of the AC drives depends on the progress in power electronics, microelectronics, control methods, artificial intelligent techniques and so on. Fuzzy Logic Concept (FLC), one of the Artificial Intelligent methods has found high applications in most of the nonlinear systems like the electric motor drives. FLC can be used as controller for any system without requirement of the system mathematical model unlike that of the conventional electrical drive control, which uses the mathematical model. Due to the usage of the FLC concept, the efficiency, reliability & performance of the AC drives increases. In view of the...

8. Diagnosis of dynamic systems does not necessarily require simulation - Andreas Malik; Peter Struss
We present a paradigmatic example of a feedback-controlled system: an electric motor with sensor and controller. Diagnosis of this system is performed based on a qualitative model that reflects deviations of parameters and behavior from a fixed reference state. The hypothesis that has been examined in this case study is that detection of behavior discrepancies does not necessarily require simulation of behavior, but can be done by checking (qualitative) states only. The qualitative models and the state-based diagnosis algorithm proved to establish a basis sufficient for fault detection and fault identification in the motor example. Some of the general preconditions...

9. A Structural Empirical Model of R&D, Firm Heterogeneity and Industry Evolution,” Working Paper - Daniel Yi Xu
This paper develops and estimates a dynamic industry equilibrium model of R&D, R&D spill-overs, and productivity evolution of manufacturing plants in the Korean electric motor industry from 1991 to 1996. Plant-level decisions for R&D, physical capital investment, entry, and exit are integrated in an equilibrium model with imperfectly competitive product market. Estimates of the structural parameters explains observed heterogeneity in plant R&D choice, size, and turnover, and quantifies how R&D and R&D spill-overs drive the change of plant productivity and industry structure. Given the structural estimates, I study an important policy question: how does product market competition affect individual firm...

10. Test Methods for Determining the Impact of Motor Condition on Motor Efficiency and Reliability - Dr Howard; W. Penrose; Ph. D
This article discusses the financial impact of motor condition on electric motor efficiency and reliability by reviewing a combination of Motor Circuit Analysis (MCA) and vibration techniques. Cost impacts on energy, production and maintenance will be outlined. The topic will surround a utility study and US Department of Energy market transformation success during 2000 and 2001. The primary areas of concern are phase balance, rotor bars, cleanliness and bearing issues.

11. Comparison of some Techniques for Learning-Based Pattern Classification in Technical Diagnosis - Einar Lihovd; Magnus RASMUSSEN
This paper reports a comparison study of 5 selected techniques for learning-based pattern classification. The techniques are the Linear Discriminant, the k-Nearest Neighbour Rule, the Classification Tree, and the 2 types of feed-forward artificial neural networks called the Backpropagation network and the Cascade-Correlation network. Each technique is briefly introduced and a test case involving a centrifugal pump driven by an electric motor is then presented. An extensive set of vibration and process measurements was collected for the machinery both in healthy and faulty conditions, and this was then used for training and testing the different classifiers. Key Words: Learning-based pattern...

12. Casa aïllada energèticament sostenible: subministrament elèctric i optimització d'energia tèrmica - RIPOLL MONTELL, JORGE
[VAL] Al present treball s’estudien dos sistemes que aprofiten la radiació solar per generar energia tèrmica i elèctrica, minimitzant l’ús de combustibles fòssils. Per aconseguir-ho, s’ha dimensionat una instal·lació completa de captació solar tèrmica amb emmagatzemament d’aigua, per a ser consumida quan així ho requereix la demanda, a més, d’una instal·lació solar fotovoltaica capaç de generar energia elèctrica per consum directe dels receptors existents a la vivenda, tot amb l’estudi de la possible demanda energètica dels usuaris i en funció de l’època de l’any d’utilització. El projecte valora les opcions possibles d’instal·lació i les decisions es prenen pensant en la cobertura energètica...

13. 1 - Mário Cesar; E. S. Ramos; Geraldo F. Burani; Mário Cesar; G. Ramos
Abstract:- This paper shows a methodology for assessment and optimization of induction electric motors aiming energy conservation, through substitution of older electric motors by high-efficiency ones, including motor resizing, aided by computer simulation. Energy Diagnosis aims to provide the client with a decrease in electric energy costs, not only a decrease in demand, but as well as a decrease in consumption. This study and its application were carried out through the Electric Energy Efficiency Program promoted by the Brazilian Electric Energy Agency. These programs, which can be financed by the utilities, arouse the interest for the implementation of energy efficiency...

14. $rec.titulo - High-speed Low; Power Radial; Free Heatpumps; Jurg Schiffmann; Daniel Favrat
The presence of oil in domestic heat pumps is a hindrance, particularly for enhanced surface evaporators and for advanced concepts based on two-stage cycles. Very compact oil-free dynamic compressor directly driven by high speed electric motors and supported on refrigerant vapor bearings represent a promising alternative. This paper presents a design analysis of the first stage prototype with the various tradeoffs between the impeller characteristics to follow the seasonable heat demand, the bearing and rotor stability and the constraints linked with the high speed electric motor. Refrigerant chosen for the first experimental approach is HFC 134a with a 20 mm...

15. Optimizing Voltage-Frequency Control Strategy for Single-Phase Induction Motor Drives - N. Naewngerndee; C. Sukcharoen; T. Kulworawanichpong
Abstract:- Single-phase induction motors are widely used in household electric motor applications. Although most electric appliances require a few amount of kilo-watt input, minimizing power losses during their operation gives a great benefit resulting in nationwide electric energy used by householders. In this paper, a model-based simulation for loss minimization using the space-phasor theory is proposed. Instead of a fixed 220 V, 50 Hz AC power source, a variable-voltage,variable-frequency (VVVF) control scheme is assumed to function the AC supply. By formulating and solving a constrained optimization of single-phase induction motor drives with VVVF, operation of the single-phase induction motor with...

16. Propulsion Electric Grid Simulator (PEGS) for Future Turboelectric Distributed Propulsion Aircraft - Choi, Benjamin B.; Morrison, Carlos; Brown, Gerald V.; Dever, Timothy
NASA Glenn Research Center, in collaboration with the aerospace industry and academia, has begun the development of technology for a future hybrid-wing body electric airplane with a turboelectric distributed propulsion (TeDP) system. It is essential to design a subscale system to emulate the TeDP power grid, which would enable rapid analysis and demonstration of the proof-of-concept of the TeDP electrical system. This paper describes how small electrical machines with their controllers can emulate all the components in a TeDP power train. The whole system model in Matlab/Simulink was first developed and tested in simulation, and the simulation results showed that...

17. Improving the performance of μ-ORC systems - Declaye, Sébastien
This thesis contributes to the knowledge and the characterization of micro Organic Rankine Cycles (ORC). It is based on experimental data and simulation models. An oil-free scroll expander is tested in a wide range of operating conditions in order to better characterize its performance. Particular attention is paid to the tightness of the machine which is obtained using a magnetic coupling. The measured isentropic efficiency reaches 75% which is higher than typical values reported in the literature. From the experimental results, a performance map of the expander is generated. This performance map can be used to provide fast and accurate calculation...

18. Cálculo y diseño de un reductor de velocidad de 11 kw para el accionamiento de una cinta transportadora de granulado de biomasa - BLASCO NAVARRO, PABLO
El presente proyecto marca como objetivo el diseño y cálculo de un reductor de velocidad que permita el accionamiento de una cinta transportadora para el granulado de pelets. Su función consistirá en transmitir una potencia proporcionada por un motor eléctrico a la cinta mediante un mecanismo que permite el giro. Los materiales de construcción del reductor estarán de acuerdo con la potencia a transmitir y su par. Lo normal es la fabricación con acero en sus diferentes tipos o aleaciones. La necesidad de introducir un reductor viene a partir del requerimiento indispensable de adecuar la velocidad de giro y par aportados por el motor eléctrico, consiguiendo el funcionamiento del equipo...

19. Diseño de reductor de velocidad para máquina de cortar madera - LÓPEZ IBÁÑEZ, JACOBO
El objeto de este proyecto es el de diseñar y dimensionar un aparato reductor de velocidad con dos etapas accionado por un motor eléctrico. Dicho reductor será utilizado para mover los rodillos de una cinta transportadora de viruta situada a la salida de una sierra de corte. La potencia a transmitir es de 300 w. a una velocidad de 175 r.p.m.. El reductor deberá funcionar de forma continua durante 24 h/día. Se utilizarán engranajes cilíndricos de dientes rectos y ejes paralelos. Teniendo en cuenta que el reductor es accionado por un motor eléctrico a 1400 r.p.m., obtenemos una relación total de transmisión a conseguir i = 8. El...

20. Diseño y simulación de un vehículo híbrido eléctrico de alta eficiencia y bajas perdidas - MARTÍNEZ FERNÁNDEZ, JAVIER
[EN] With fossil fuels price rising and the air quality lowering, the need for new propulsion schemes becomes clear, especially in big cities. Facing the rising needs of viable alternatives, this project aims at developing and realizing a new hybrid propulsion system which is capable of merging efficiency, low fuel consumption and good performance. This Master Thesis describes the design of a hybrid automobile and shows that good performance can be achieved together with high efficiency and low fuel consumption. To achieve this goal, a high power electric motor is used in conjunction with a light weight and aerodynamic chassis, an efficient...

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