SUPERCONDUCTING LINEAR SYNCHRONOUS MOTOR PROPULSION AND MAGNETIC LEVITATION FOR HIGH SPEED GUIDED GROUND TRANSPORTATION. PHASE III INTERIM REPORT
After the commissioning of a six-component force balance and adjustment system, the wheel facility (7.6 m diameter, 0-100 km/h) was used for a large-scale linear synchronous motor test program. Rim-mounted "stator" windings, energized from a 42 kVA inverter, interacted with a stationary superconducting magnet. The measured forces, their harmonics, and terminal characteristics agree well with analysis based on mutal inductance computations and a coupled circuit model. The LSM is underdamped under open loop conditions, and closed loop stability has been demonstrated both by internal inverter power factor angle control and by the use of "vehicle" position detectors. Control strategies are being examined by computer modelling of LSM dynamics, and are being implemented in a small-scale LSM test track. Analysis of ladder levitation guideways shows that a pure inductive model yields useful results at crusing speed, while a more rigorous resistive-inductive model must be used at lower speeds. Good lift/drag ratios with low force pulsations are possible. A scalar potential approach has been developed to determine the eddy current distribution and force on a magnet moving at high speed over a conducting guideway. Analysis of the dynamics of the strip levitation system shows that, while appreciable damping is evident at low speed, all modes are highly underdamped at cruising speed. A similar conclusion is reached for the null-flux loop guidance scheme. A secondary suspension has been incorporated into the reference design. High damping factors can be achieved with a novel passive secondary magnetic damping scheme. Small perturbation analysis shows that the appropriate location of springs and dampers in the secondary suspension leads to dynamic stability with reasonable ride quality. Supplementary active control through hydraulic actuators is being considered. Analysis of isochoric operation of the superconducting magnets has been extended to abnormal heat leaks. Overpressure relief valves, venting at 20 Atm, are proposed. An interim reference design describes the proposed Maglev vehicle design and the characteristics of its sub-systems.
- Sponsored by the Transportation Research & Development Center, Canada.
Canadian Institute of Guided Ground TransportQueen's University
Kingston, Ontario K7L 3N6, Canada
- Publication Date: 1976-3-31
- Features: Appendices; Figures; References; Tables;
- Pagination: 280 p.
- TRT Terms: Cryogenics; High speed ground transportation; Intelligent transportation systems; Linear motors; Magnetic levitation; Synchronous motors; Test facilities; Vehicle dynamics
- Old TRIS Terms: Advanced systems
- Subject Areas: Operations and Traffic Management; Public Transportation; Railroads;
- Accession Number: 00158202
- Record Type: Publication
- Source Agency: Canadian Institute of Guided Ground Transport
- Report/Paper Numbers: CIGGT-76-7 Intrm Rpt.
- Contract Numbers: OST5-0112
- Files: TRIS
- Created Date: Aug 31 1977 12:00AM