Efficiency of ferromagnetic shielding of superconducting coils of high-speed maglev crew

Abstract

Background: Magnetic levitation transport with combined traction, suspension and guidance systems based on superconducting coils (SCC) allows reaching speeds of up to 500600 km/h with a very significant (up to 150200 mm) air gap, which is an important factor in ensuring the safety of high-speed transportation. However, SCC are a source of strong external magnetic fields, which, in conditions of limited crew dimensions, can have a harmful effect on both passengers and on-board auxiliary equipment.
 Aim: to analyze the external magnetic fields of the SCC systems for traction, suspension and direction of maglev vehicles and the effectiveness of ferromagnetic screens as a means of ensuring the electromagnetic safety of passengers and the electromagnetic compatibility of the SCC with other onboard equipment.
 Materials and methods: to achieve this goal, methods of analytical and numerical modeling of the magnetic fields of the SCC using modern software packages were used. As a prototype of the combined magnetic system of traction, suspension and direction, the system of the MLX-L0 maglev vehicle, which is undergoing pilot commercial operation at the Yamanashi test line (Japan), was adopted.
 Results: it is shown that the value of the external magnetic fields of the SCC of the traction and guiding systems in the passenger cabin of the prototype crew exceeds the maximum permissible levels established by domestic and foreign regulatory documents, both without shielding and with passive shielding with flat steel sheets.
 Conclusion: passive shielding of the SCC with steel sheets, including multilayer ones, does not provide the required reduction in the level of external magnetic fields for a given vehicle dimensions.