Graduate Thesis Or Dissertation
 

Investigation, analysis and design of the linear brushless doubly-fed machine

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/v118rg790

Descriptions

Attribute NameValues
Creator
Abstract
  • This thesis covers the efforts of the design, analysis, characteristics, and construction of a Linear Brush less Doubly-Fed Machine (LBDFM), as well as the results of the investigations and comparison with its actual prototype. In recent years, attempts to develop new means of high-speed, efficient transportation have led to considerable world-wide interest in high-speed trains. This concern has generated interests in the linear induction motor which has been considered as one of the more appropriate propulsion systems for Super-High-Speed Trains (SHST). Research and experiments on linear induction motors are being actively pursued in a number of countries. Linear induction motors are generally applicable for the production of motion in a straight line, eliminating the need for gears and other mechanisms for conversion of rotational motion to linear motion. The idea of investigation and construction of the linear brushless doubly-fed motor was first propounded at Oregon State University, because of potential applications as Variable-Speed Transportation (VST) system. The perceived advantages of a LBDFM over other LIM's are significant reduction of cost and maintenance requirements. The cost of this machine itself is expected to be similar to that of a conventional LIM. However, it is believed that the rating of the power converter required for control of the traveling magnetic wave in the air gap is a fraction of the machine rating. The constructional design of the machine is such that the primary contains two 3-phase windings. One of these 3-phase systems is connected directly to the utility grid; the second 3-phase system, with a different number of poles, is connected to a power electronic converter which has the capability of providing adjustable frequency and amplitude of voltage or current. The speed of the traveling magnetic field can be varied simply by controlling the output frequency of the power electronic converter. The design of the actual machine is such that the two 3-phase systems laid in the primary of the machine are magnetically decoupled from each other because of the difference in pole number of the two systems, (e.g. 6-pole and 2-pole for the test prototype machine in our research lab). The other degree of freedom that this machine provides, is the operation of the machine under two distinct speeds by implementing the pole change technique. This mode of operation can give only discrete changes in speed, however, it provides efficient running at those speeds with a minimum of control mechanism. On the other hand, it is anticipated that the LBDFM with two actively fed windings will produce a continuously adjustable speed over a wide range. Hence, LBDFM will be superior if it can be designed to function effectively.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 8-bit Grayscale) using ScandAll PRO 1.8.1 on a Fi-6770A in PDF format. CVista PdfCompressor 5.0 was used for pdf compression and textual OCR.
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details SeifkhaniFarroh1991.pdf 2017-08-04 Public Download