Chinasigned off 2025 with a breakthrough when its magnetic levitation train attained 700 km/hr speed in 2 seconds in a testmaking it the fastest Maglev train,ever. Maglev (magnetic levitation) trains work on the principle of electromagnets. We all have played with magnets in our childhood and were told by our teachers that a magnet has a north and a south poleand like poles repel and unlike poles attract. Electromagnets differ from permanentmagnets because its magnetic pull is temporary and will last till it is connected to an electric source. If the repulsive forces of two like poles are strong enough it will lead to levitation. Thus, levitation is floating of an object in air without any physical support overcoming the gravitational force. Unlike flying, levitation implies a stable, suspended position.
Let me explain the basic mechanism of Maglev train in a very simple way.There are two main components: i) Magnetized coils inside the tracks called the guideway and ii) Large magnets on train’s undercarriage. Both these are configured in a way that it repels levitating the entire train up to 10 centimetres above the tracks. To propel the levitated train forward, power is supplied to the magnetized coils resulting in rapidly switching the north and south poles of the electromagnets on the tracks. This creates a magnetic wave that pushes and pulls the train forward in levitated position with the front magnets repelling and rear magnets attracting the train’s onboard magnets to maintain continuous, high-speed motion. The aerodynamic design of the Maglev trains and frictionless movement allow these trains to reach unprecedented ground transportation speeds of over 600 km/hr. Just imagine travelling to Delhi from Hyderabad in less than 3 hours, a distance of over 1600 kms.
What does the future hold for Maglev trains? In my opinion we are still decades away when Maglev trains will operate on a regular basis. The reasons could be several from having straight and flat tracks or with large curves passing though cities, mountains and valleys. This requires drilling deep tunnels and construction of bridges, addressing issues like right of way requiring lots of demolition and displacement of people in cities and other environmental issues. All this will make the project prohibitively expensive. In a democratic country like India where all politics is local rather than centralised, it is an impossible dream unlike China which is an authoritarian one-party state under communist regime. This is probably the reason that Maglev has not taken off since its conceptualisation in the early 20th century and the first Maglev prototype non-commercial monorail in Germany in the later part of the century.Currently, China, South Korea, and Japan operate Maglev trains mostly as air terminal transfers. The longest Maglev train is Shanghai’s Pudong International Airport to city (Longyang Road station) in 8minutes covering a distance of over 30 km at a top speed of 430 km/hr.
– Dr. RK Chadha
