There are two types of electromagnets used in magnetic levitation: normal conducting electromagnets and superconducting electromagnets. The conductive material of the conventional electromagnet is a commonly used metal conductive material with a certain resistance. In order to suspend the carriage of dozens or even hundreds of tons against gravity, the magnetism of the electromagnet is required to be very strong, and thus the current through the conductor is required to be very large. A large amount of heat is generated when a large current flows through a conductor with resistance. Therefore, there must be a large amount of cooling water to help it dissipate heat when the electromagnet is working. This causes the equipment to be bloated and complicated, which is particularly troublesome. The conductive material of a superconducting magnet is a superconducting material, that is, a material that loses electrical resistance at low temperatures. If a high-temperature superconducting material is used to make a conductor, just immerse it in liquid nitrogen at minus 196°C, and the resistance will disappear, and no matter how much current is passed, it will not heat up. Therefore, the superconducting magnet does not need the cooperation of the bulky cooling system when working, and is much lighter and more flexible than the conventional electromagnet. Of course, in order to maintain its extremely low temperature working state, the technical requirements are much higher.
Post time: Aug-06-2022