How does magnetic levitation trains work?
The maglev train operates based on one out of the four fundamental forces of nature, the electromagnetic force. The maglev train basically functions by using the attraction and repulsion of electromagnetic forces to move the train forward while levitating.
But how does a heavy train levitate and operate at the same time?
There are two methods that levitation can influence the maglev train's levitation and guidance, that is the electromagnetic suspension (EMS) and the electrodynamic suspension (EDS). Electromagnetic suspension is responsible for the levitation and guidance of the maglev train, it uses attractive forces and this method is used by the Germans. On the other hand, electrodynamic suspension is responsible for the levitation that guides the maglev train above the track using repulsive forces and this is used by the Japanese. Although there are two methods, EMS and EDS, the EDS is more efficient than the EMS because the EDS provides both levitation and propulsion whereas EMS only provides levitation. The propulsion for the EMS is needed from another source, therefore electrodynamic suspension will be focused on instead of electromagnetic suspension.
Electrodynamic Suspension (EDS)
Electrodynamic suspension used by the Japanese is the idea that the same two electromagnetic forces are positioned at the undercarriage of the maglev train and on the track, this creates a repulsion force because two-like forces repel thus resulting in the levitation of the maglev train. In addition, electromagnetic forces are positioned on the side of the guideway, this creates propulsion, the force in which the maglev train moves forward. The propulsion is created when magnetic fields are created from electricity flowing through the supercondutors on the guideway tracks.
The maglev train operates based on one out of the four fundamental forces of nature, the electromagnetic force. The maglev train basically functions by using the attraction and repulsion of electromagnetic forces to move the train forward while levitating.
But how does a heavy train levitate and operate at the same time?
There are two methods that levitation can influence the maglev train's levitation and guidance, that is the electromagnetic suspension (EMS) and the electrodynamic suspension (EDS). Electromagnetic suspension is responsible for the levitation and guidance of the maglev train, it uses attractive forces and this method is used by the Germans. On the other hand, electrodynamic suspension is responsible for the levitation that guides the maglev train above the track using repulsive forces and this is used by the Japanese. Although there are two methods, EMS and EDS, the EDS is more efficient than the EMS because the EDS provides both levitation and propulsion whereas EMS only provides levitation. The propulsion for the EMS is needed from another source, therefore electrodynamic suspension will be focused on instead of electromagnetic suspension.
Electrodynamic Suspension (EDS)
Electrodynamic suspension used by the Japanese is the idea that the same two electromagnetic forces are positioned at the undercarriage of the maglev train and on the track, this creates a repulsion force because two-like forces repel thus resulting in the levitation of the maglev train. In addition, electromagnetic forces are positioned on the side of the guideway, this creates propulsion, the force in which the maglev train moves forward. The propulsion is created when magnetic fields are created from electricity flowing through the supercondutors on the guideway tracks.
Going more in-depth on how the levitation and propulsion function together effectively on a maglev train based on electrodynamic suspension is through the use of coils. Coils are found on the edge of the guideway and wrapped around them is a superconductor. Being a superconductor, electricity flows through the them with no difficulty as there is no resistance, the coils produce a magnetic field of north and south forces.
So how does propulsion come into play?
So how does propulsion come into play?
As a result from the coils creating the north and south magnetic forces, these forces on the guideway repel and attract to the north and south forces on the side of the maglev train, created from coils cooled in liquid helium so it does not over heat the train. This attraction and repulsion that causes the maglev train to propel forward can be seen in step 1 of Figure 3 as the south magnetic force on the edge of the train is attracted to the north magnetic force located on the guideway (green arrow connecting yellow 'S' box to blue 'N' box, top right of the train in step 1). This force causes the train to move forward. In addition, repelling forces also push the train forward as seen in step 1 of Figure 3, the north magnetic force on the edge of the train repels away from the north magnetic force on the guideway (red arrow connecting blue 'N' box of the train to the blue 'N' box of the guideway).
After the train moves forward the train runs into a problem, the forces of magnetism cause the train to repel and attract backwards, thus resulting the train to stay in one spot. To solve this problem, engineers change the polarity of the coils, creating the opposite force than it originally was, an example of this is seen in Figure 3 step 2 where the forces of magnetism at the top of the guideway is north, south north, etc. whereas in step 1 of Figure 3, the magnetic forces of the coils start as south, north, south and so on (top of step 1). Engineers successfully alternate these forces by using A/C current on the coils. As the polarity of the guideways are changed continuously , it allows the train to propel forward, using the attraction and repulsion forces. The magnetic forces on the train "chase" the forces on the guideway (magnetic field created by the coils move forward) which results in the movement of the train.
After the train moves forward the train runs into a problem, the forces of magnetism cause the train to repel and attract backwards, thus resulting the train to stay in one spot. To solve this problem, engineers change the polarity of the coils, creating the opposite force than it originally was, an example of this is seen in Figure 3 step 2 where the forces of magnetism at the top of the guideway is north, south north, etc. whereas in step 1 of Figure 3, the magnetic forces of the coils start as south, north, south and so on (top of step 1). Engineers successfully alternate these forces by using A/C current on the coils. As the polarity of the guideways are changed continuously , it allows the train to propel forward, using the attraction and repulsion forces. The magnetic forces on the train "chase" the forces on the guideway (magnetic field created by the coils move forward) which results in the movement of the train.