NTL Record

Title A Study of Linear Induction Motor Characteristics: The Oberretl Model
Record ID 47131
Personal Name
Creator
Stickler, John J.
Source 48p. in various pagings
Corporate Creator John A. Volpe National Transportation Systems Center (U.S.)
Corporate
Contributor
United States. Department of Transportation. Federal Railroad Administration. Office of Research and Development
Publisher John A. Volpe National Transportation Systems Center (U.S.)
Publication Date 19750530
Language English
Abstract The Oberretl theory of the double-sided linear induction motor (LIM) is examined, starting with the idealized model and accompanying assumptions, and ending with relations for predicted thrust, airgap power, and motor efficiency. The effect of varying the maximum transverse harmonic order on the transverse primary current density and airgap flux density is considered. The Oberretl theory is seen to lead to excessively large flux densities in the regions adjacent to the primary which results in an overestimate of the normal attractive forces at small motor slip frequencies. A comparison of the LIM forces predicted by the Oberretl and Elliott models is given for the Tracked Levitated Research Vehicle (TLRV) and the LIM Research Vehicle (LIMRV) LIMs. The Oberretl theory gives thrust in good agreement with those of Elliott for the LIMRV; for the TLRV, the Oberretl theory predicts thrust about 20% greater than those predicted by Elliott. The corresponding normal forces predicted by the Oberretl theory were approximately three times greater than those predicted by Elliott. A computer program developed as part of this study program is given in the appendix. It requires computing times of the order of 50 seconds for typical runs consisting of ten case points.
Rosap ID dot:9754
Rosap URL https://rosap.ntl.bts.gov/view/dot/9754
TRT Terms Linear induction motors; Magnetic levitation vehicles; Computer programs; Thrust
General Subjects Linear induction motor; LIM propulsion characteristics; End-effect; Oberretl theory
Geographical
Coverage
United States
Contract Number RR505/R5316
Report Number DOT-TSC-FRA-75-2; FRA-ORD-75-72
Availability Volpe National Transportation Systems Center, Technical Reference Center
Resource type Tech Report
URL https://ntlrepository.blob.core.windows.net/lib/47000/47100/47131/DOT-TSC-FRA-75-2.pdf
Format PDF
Database NTL Digital Repository