IRON-CORE SUPERCONDUCTING MAGNET DESIGN AND TEST-RESULTS FOR MAGLEV APPLICATION

Design and test results are presented for a superconducting electromag net for levitating and propelling Maglev vehicles at high velocities. A U-shaped iron core carries a superconducting magnet around its back leg and a normal control coil around each leg of the U-core, The open side of the U-core is bridged by an iron rail through a large airgap b etween the poles of the U-core and the iron rail, The superconducting magnet is nominally designed to operate in a steady-state de mode with current variations limited to rates less than 1 Hz, Faster flux varia tions due to gap changes are accommodated by current changes in the no rmal control coils, A Feedback controller using the airgap and acceler ation inputs controls current variations in the superconducting coil. Grumman has designed, fabricated and tested such an electromagnet, Thi s test magnet is 2/3 of the full-size magnet that Grumman specified in their 1992 Concept Definition Study for the National Maglev Initiativ e, The purpose of these tests is to demonstrate the feasibility of ope rating and controlling a superconducting electromagnet in the specifie d environment, This paper discusses static magnet levitation character istics as functions of airgap length and superconducting magnet excita tion. Good correlation is observed between the calculated and measured performance.