IMPROVING THE VIBRATORY BEHAVIOR OF A FLEXIBLE PLATE USING COMBINED EXPERIMENTAL MEASUREMENTS AND F.E. MODELLING
- F. Mabrouki; M. Thomas; A. A. Lakis
In this paper, we will be combining experimental modal analysis and finite-element modeling to re-design a base plate of a mechanical system made up of steel sheets in order to reduce its level of vibrations, which are responsible for undesirable noises. The new model to be designed must be longer than the current one, and it was agreed with our industrial partner that the solution to be proposed must not generate additional production costs, i.e., we must only modify the shapes of the base plate to rigidify it, without adding any damping materials. To come up with a new design...
Respuesta transitoria de transformadores eléctricos en presencia de variadores de velocidad en instalaciones petroleras de bombas sumergibles
- Pajón Ruíz, Héctor Javier
Resumen: A partir de un modelo teórico se estudia el comportamiento del devanado de un transformador con el objetivo de encontrar la distribución de sobretensiones a lo largo del mismo y así establecer posibles puntos de falla en presencia de transitorios provocados por la onda PWM producida por los variadores de velocidad en instalaciones de extracción de petroleo. En este estudio se incluyen los componentes de la instalación eléctrica de extracción de petroleo como por ejemplo, los conductores primario y secundario del transformador; el motor de la bomba eléctrica sumergible, el variador de velocidad con salida tipo PWM y por...
Life-Cycle Cost Sensitivity to Battery-Pack Voltage of an HEV
- John W. Mckeever; Sujit Das; Leon M. Tolbert; Laura D. Marlino; Ashok Nedungadi
A detailed component performance, ratings, and cost study was conducted on series and parallel hybrid electric vehicle (HEV) configurations for several battery pack and main electric traction motor voltages while meeting stringent Partnership for a New Generation of Vehicles (PNGV) power delivery requirements. A computer simulation calculated maximum current and voltage for each component as well as power and fuel consumption. These values defined the peak power ratings for each HEV drive system’s electric components: batteries, battery cables, boost converter, generator, rectifier, motor, and inverter. To identify a superior configuration or voltage level, life cycle costs were calculated based on...
- Willard D. Childs; P. E. (vpc; Ali E. Dabiri
t2b. 0tSTRlS”TtON CODE This study was died toward combiig the VARI-RO Direct Drive Engine (VRO-DDE) technology with the highly efftcient VARI-RO Electric Motor Drive (VRO-EMD) integrated pumping and energy recovery system for reverse osmosis (RO) desalting. The engine technology provides the capability to use diit thermal power to replace more expensive electric power. The ways that the VRO-DDE techttology reduces desalting cost, and enviroomeotal impact, includes the following: 1) use of RO. the most energy efficient desalination process; 2) use of efficient positive displawmem pumping and energy recovery; 3) use of thermal energy sources that are lower cost tbao electricity;...
2 Woods Holes Oceanographic Institution.
- Moshe Alamaro; Kerry A. Emanuel; Wade R. Mcgillis
Abstract. Thermodynamic analysis and numerical modeling of hurricane intensity has shown that it is sensitive to enthalpy and momentum transfer from the ocean surface. Direct measurements of drag are not easily performed on the high seas. Therefore, an annular wind wave tank has been constructed in which aspects of a tropical storm boundary layer were simulated. The air velocity inside the annular tank is comparable to that of a hurricane. This paper focuses mainly on the design and engineering of the tank, the fluid mechanics of the rotational flow in the tank using angular momentum analysis, the design of experiments,...
Research on Quieter Cars and the Safety of Blind Pedestrians A Report to Congress Prepared by:
People who are blind have expressed concern that the proliferation of quieter cars, such as hybrid electric vehicles (HEV), may affect pedestrian safety negatively. These vehicles, when driven at slow speeds, are more likely to operate on their electric motor system, resulting in minimal engine sound when other auditory cues from tires and wind noise may also be diminished. While this may be a beneficial outcome for environmental noise reduction, it may pose a safety problem for pedestrians. Pedestrians who are blind are particularly affected because they rely even more heavily on these auditory cues to identify the presence of...
Refrigerant-Side Evaporation and Condensation Studies
- J. S. Panek; J. C. Chato; J. M. S. Jabardo; A. L. De Souza; J. P. Wattelet; Richard W. Kritzer; Air Conditioning
founded in 1988 with a grant from the estate of
Effect of PWM inverters on ac motor bearing currents and shaft voltages
- Jay Erdman; Russel J. Kerkman; Dave Schlegel; Gary Skibinski
Abstract- This paper investigates AC induction motor shaft voltage problems, current flow thru motor bearings and electric discharge current problems within bearings when operated under both pure sinewave and Pulse Width Modulated (PWM) inverter sources. Recent experience suggests that PWM voltage sources with steep wavefronts especially increase the magnitude of the above electrical problems, leading to motor bearing material erosion and early mechanical failure. Previous literature suggests that shaft voltage-bearing current problems under 60 Hz sinewave operation are predominantly electromagnetically induced. It is proposed that under PWM operation these same problems are now predominantly an electrostatic phenomenon. A system model...
Graphical User Interface Aided Online Fault Diagnosis of Electric Motor- DC Motor Case Study
- Seda Postalcioglu Ozgen
Abstract—This paper contains graphical user interface (GUI) aided online fault diagnosis for DC motor. The aim of the research is to prevent system faults. Online fault diagnosis has been studied. Design of fault diagnosis has two main levels: Level 1 comprises a traditional control loop; Level 2 contains knowledge based fault diagnosis. Fault diagnosis technique contains feature extraction module, feature cluster module and fault decision module. Wavelet analysis has been used for the feature extraction module. For the feature cluster module, fuzzy cluster has been applied. Faults effects are examined on the system using statistical analysis. In this study Fault...
Statement of Research Interests
- Peter Korošec
In my master thesis I was working on an ant-based method called the Multiple Ant Colony Algorithm , which can be successfully used to solve a type of clustering problem called the graph-partitioning problem, which is one of the hard combinatorial optimization problems. In my doctorate dissertation I was working on a novel method based on stigmergy for solving numerical (multi-parameter) optimization problems. Here I proposed a general approach for the translation of a multi-parameter problem into a search graph representation, where each longest path in the search graph represents one possible solution, and all the longest paths together represent...
2.141: Modeling and Simulation of Dynamic Systems
- Thomas A. Bowers
This paper discusses the dynamic analysis and simulation of a heat gun. The system consists of an electric heating coil and a universal AC electric motor that drives a centrifugal fan in order to produce airflow. A diagram of the system is shown in Figure 1. Although the system looks relatively simple there are complex interactions between
Kinematic Design of a Three Degree of Freedom Parallel Hand Controller Mechanism
- Bernard D. Adelstein; Peter Ho; H. Kazerooni
This paper presents the kinematic design of a 10 link “inparallel” mechanism for use in a three degree of freedom forcereflecting haptic interface. The mechanism linkage couples three coplanar rotary electric motor shafts to the endpoint grasped by the human operator. The linkage permits all motor housings to be supported on a common base, thereby reducing the inertia and weight that the interface actuators and human operator must support and move. Furthermore, because only rigid links and rotary ball bearings are used, the linkage avoids the compliance, friction, and/or backlash associated with other types of transmission elements. The linkage workspace...
Electric motor-driven systems are estimated to consume over half of all electricity in the United States and over 70 % of all electricity in many industrial plants. This fact sheet presents an overview of electric drive systems and highlights common ways you can improve system efficiency and reliability. By optimizing the efficiency of your motor-driven systems, you can increase productivity while saving significant amounts of energy and money.
REPLACING AN OVERSIZED AND UNDERLOADED ELECTRIC MOTOR
This fact sheet will assist in decisions regarding replacement of oversized and underloaded motors. It includes a discussion of how the MotorMaster software can be used to conduct motor replacement analyses. Motors rarely operate at their full-load point. Field tests of 60 motors at four industrial plants indicate that, on average, they operate at 60 % of their rated load. 1 Motors that drive supply or return air fans in heating, ventilation and air-conditioning (HVAC) systems generally operate at 70 % to 75 % of rated load. 2 A persistent myth is that oversized motors, especially motors operating below 50...
Industrial Electric Motor Systems Market Opportunities Assessment
- United S
(DOE) Office of Energy Efficiency and Renewable Energy (EERE) in December 1998. As of fiscal year 2000, DOE’s Motor Challenge Program was integrated into BestPractices, a broad initiative within EERE. EERE’s BestPractices introduces industrial end users to emerging technologies and cost-saving opportunities in widely used industrial systems. Best-Practices offers resources, tools, and information. Thus, industrial end users can match new and verified energy-efficient technologies and practices to their individual plant needs. Since the original printing, there have been some minor changes. The inside and outside back cover (last two pages) were deleted because they contained outdated program information. In addition,...
Electric Motor Model Repair Specifications
- Bonneville Power Administration; General Requirements
These Model Repair Specifications are intended to cover routine repair and rewind of low-voltage random-wound three-phase AC squirrel cage induction motors. For motors falling outside this description, the more comprehensive model specifications below are recommended.
The following series of Repair Documents—The Service Center Evaluation Guide, Selected Bibliography on
- Chuck Yung Easa; Tom Bishop; Longo Industries; Wallace Brithinee; Brithinee Electric; Lynda Butek; Brithinee Electric
Electric Motor Repair, Model Repair Specifications for Low Voltage Motors, and Motor Repair Tech Brief— were produced by the U.S. Department of Energy’s Office of Industrial Technologies (OIT) with input from trade associations, consulting companies, manufacturers, non-profit corporations, and others. OIT would like to thank the individuals and organizations who participated in the review meetings and those who contributed valuable technical review of and input into the development of the Repair Documents. Doug Baston, Northeast Energy Efficiency Partnerships
Ford Motor Company Frigidaire Company General Electric Company
- K. M. Stone; S. P. Vanka; Air Conditioning; A. M. Jacobi; T. A. Newell; S. P. Vanka; Principal Investigators; The Air Conditioning; Brazeway Inc
facilities. The ACRC receives continuing
An Experimental and Numerical Study of Flow and Heat Transfer in Louvered-Fin Heat Exchangers
- Heat Exchangers; L. Zhang; S. Balach; F. M. Najjar; D. K. Tafti; S. Balach; A. M. Jacobi; Principal Investigators; The Air Conditioning; Brazeway Inc
was founded in 1988 with a grant from the estate of Richard W. Kritzer, the founder of Peerless of
or implied, by the National Aeronautics and Space Administration. NASA’S INVOLVEMENT IN TECHNOLOGY DEVELOPMENT AND
- Larry A. Viterna; Either Expressed; Larry A. Viterna; Ph. D
Abstract: A government and industry cooperative is using advanced power technology in a city transit bus that will offer double the fuel economy, and reduce emissions to one tenth of government standards. The heart of the vehicle's power system is a natural gas fueled generator unit. Power from both the generator and an advanced energy storage system is provided to a variable speed electric motor attached to the rear drive axle. A unique aspect of the vehicle's design is its use of "super " capacitors for recovery of energy during braking. This is the largest vehicle ever built using this...