Maglev trains use magnetic levitation technology to levitate themselves along a track without the use of wheels, making them fast, quiet, and eco-friendly options.
Superconducting electromagnets hold the train car atop a concrete guideway. Their coils and onboard magnets constantly change polarity – acting much like two toy magnets with opposite poles facing one another in this article we are discussing about magnetic levitation train work.
Power
Maglev trains differ from conventional rail transport by not creating friction between wheels and tracks, thereby decreasing energy usage and speeding travel faster than trains that rely on more traditional methods of travel.
Trains are suspended just a few inches above a track made of copper plates covered with electromagnets that work on the principle that like poles attract, while opposite ones repel. As trains pass through an electromagnetic field, this creates current in the coils beneath the track that alters magnetic flux. Pushing and pulling will move them along their paths.
As the train passes through an electromagnetic field, it generates current in its coils along its sides and underside that alters magnetic flux, drawing vehicles in like magnets on-board the train do. As such, when passing through electromagnetic fields the train generates current that generates push/pull forces that cause lift-off and acceleration of speed.
Foster-Miller experimental track achieved this by rapidly accelerating a 10-pound carrier to 57 mph in less than one second – 10 times faster than gravity alone! Other systems may differ, but all work on similar principles: one such system features copper track coils synchronized with sensors placed along its route that turn on just before coming in contact with carrier, then off again once they’ve passed over them; with sensors telling electromagnets where exactly its position was in relation to them.
Other maglev systems utilize linear motors that function similarly to an electric car engine, with moving parts (the train) and stationary ones (propulsion coils on the guideway) both acting like electric car pistons. Japan’s High Speed and Supersonic Transport Service and Central Japan Railway Company both utilise this form of magnetic levitation technology; both employ this system called SCMaglev.
Although less efficient than an EMS system, this alternative uses far less power overall and has track maintenance requirements closer to that of aircraft than traditional rail transport systems. Furthermore, its tracks are immune from weather conditions like heat deformation or freezing that impede conventional rail transport systems’ speed and range.
Track
Maglev trains are propelled forward by an invisible magnetic field which levitates and propels it. A key component of this system is its track, designed specifically to maintain minimal contact between it and the train and maintain an even gap.
The track itself utilizes electromagnets arranged in a loop to generate attractive forces underneath vehicles while repulsive forces on nearby surfaces and walls. A changing magnetic field caused by moving magnets in trains causes an electric current to flow in coils in the track, producing levitation forces and giving rise to levitation forces.
Maglev trains offer many advantages when it comes to powering them, including eliminating the need for an engine, wheels, and axles, thus significantly reducing energy consumption compared to conventional trains. Another important benefit of maglev technology is safety: because its tracks run along guideway tracks above it all the time it cannot derail.
There are two primary kinds of maglev tracks currently in use: electromagnetic suspension (EMS) and electrodynamic suspension (EDS). EMS uses magnets on both sides and underneath of the train that generate an attractive force against rails of the guideway, while EDS utilizes superconducting electromagnets arranged in an underguideway loop, with levitation coils facing each other, to produce repulsive forces against guideway walls and beneath its wheels as the train travels forward.
EDS maglev systems are the most advanced and cost-efficient systems available; however, their installation is also the most difficult and expensive. EDS requires very high speeds in order to reach sufficient velocity for levitation to take place effectively; furthermore, at lower speeds it cannot maintain an effective gap between train and guideway that remains consistent over time.
NASA’s Marshall Space Flight Center boasts an outdoor 50-foot maglev test track capable of lifting and accelerating Maglev vehicles at up to 25 mph, giving engineers the ability to test this system to gain more knowledge about how a Maglev train operates and which conditions are necessary for its smooth functioning.
Electromagnetic Suspension (EMS)
EMS systems use the magnetic attraction between magnets in the track to keep trains hovering above it by just centimeters. Furthermore, this same magnet technology also serves as propulsion – something which distinguishes maglev travel from more traditional rail travel methods.
An electric motor typically features a stationary component called the stator that surrounds a spinning component called the rotor, with current flowing through this latter piece to create a magnetic field which produces torque and spins the axle. Maglev trains use this same technology in reverse to achieve levitation.
Permanent magnets make up the stationary components in a maglev system, while rotating superconducting electromagnets act as rotating pieces. They’re placed along a guideway where trains pass over them, inducing current into them to change polarity; as they change, their magnetic forces repel underside magnets on trains, lifting them up and accelerating them forward.
At low speeds, when magnetic forces are balanced, a train is able to maintain its position with constant speed. At higher speeds however, magnetic fields change polarity quickly and cannot hold their place in place; so to combat this a feedback loop is used that continuously alters current sent to one or more permanent and superconducting magnets in order to stabilize its field’s instability.
Maglev trains can levitate with much lower power requirements than traditional railcars because they do not need to overcome rolling wheel friction. Furthermore, their maintenance requirements are lower, and they can operate even in extreme weather conditions that would normally render traditional rails unusable.
Multiple designs for maglev technology are being tested, yet all use similar principles. Some systems such as Inductrack use permanent room-temperature magnets instead of supercooled electromagnets to levitate trains; these magnets are arranged into an array similar to Halbach array and contain neodymium-iron-boron alloy that creates stronger magnetic fields than regular permanent room temperature magnets. Other designs use alternating currents with changing polarities – like EDS’ repulsive force of superconducting magnets – while EDS uses repulsive force of superconducting magnets repulsively repel each other allowing levifying trains from moving platforms.
Electrodynamic Suspension (EDS)
EDS stands out from EMS by using shifting magnetic fields to keep its train suspended. Conductors of EDS trains are exposed to time-varying magnetic fields which induce eddy currents within them; these generate repulsive force sufficient enough to overcome gravitational force and keep it suspended in place.
EDS requires less energy than EMS as only power to accelerate the train is necessary, while being more resistant to electromagnetic interference from sources like radio waves or electricity cables nearby. Furthermore, this technology also allows trains to stop or slow without needing power-intensive traction wheels to stop or slow them.
EDS guideway features electromagnetic coils which create a traveling magnetic field to propel the train forward. Furthermore, this train is powered by a linear synchronous motor that generates electricity from magnets rotating in its core; this current creates force which pushes against its rails to keep it levitating.
For creating its moving magnetic field, the core of a train contains superconducting electromagnets cooled with liquid helium or nitrogen to save energy and create the moving magnetic field. Superconductors allow electricity to continue flowing even when power is interrupted – something normal electric motor-powered trains would experience. Liquid cooling helps extend their lifetime even further and saves on energy usage.
Electromagnets in the guideway not only generate a moving magnetic field, but they also help repel the train from ground surfaces and walls, keeping it hovering a few inches above its track. This makes derailment more difficult as complete collapse would be needed to separate train from tracks; additionally, this allows trains to run regardless of weather conditions as it doesn’t rely on friction for movement.
Scientists conducted an investigation to demonstrate that maglev passengers do not notice the sound of passing trains as much. Researchers presented short sounds from passing maglev trains and asked participants to rate how annoying each one was, with results showing that magnetic levitation trains have much lower pitch and decibel levels than regular commuter trains do.
