SHUNT PROTECTION FOR SUPERCONDUCTING MAGLEV MAGNETS
Abstract Closely coupled, short-circuited shunt coils are proposed for quench protection of super-conducting Maglev magnets which use high resistance, matrix composite conductors. It is shown that, by suitable design, the shunts can reduce ac losses and that the changing currents during magnet energization or vehicle lift off and landing can be tolerated.
AC-losses in multifilamentary superconductors at technical frequencies
Multifilamentary superconductors exposed to an alternating field of small amplitude but in the technical frequency range as in a rotor of a superconducting generator show a characteristic dependence of losses on frequency. Shielding of the conductor by the induced currents is shown to be relevant. In a twisted cylindrical multifilamentary conductor the shielding currents are calculated and formulas for the hysteretic loss and eddy current loss are given as function of frequency and time constant τ of the conductor. It is shown, that a long twist length can give lower losses than a short one.
A comparison of ladder and sheet guideways for electrodynamic levitation of high speed vehicles
The basic properties of flat sheet and flat ladder levitation systems are compared and contrasted based on the assumption that identical quantities of material are used in their construction. It is shown that although ladder systems can produce slightly better lift-to-drag ratios, the overall performance of sheets is better, particularly where lateral destabilization must be minimized.