In this blog post, we will examine the principles and characteristics of hyperloop and maglev trains, as well as their potential and challenges as future modes of transportation.
Means of transportation have been developing for a long time. At first, people traveled on foot, but as the centuries passed, palanquins and rickshaws appeared, and now we see gasoline-powered cars and trains on the roads. In particular, we live in an era where we can travel from Seoul to Busan in 2 hours and 40 minutes by KTX, and to Japan in less than 2 hours by plane. These modes of transportation are deeply rooted in our lives and have become indispensable. Therefore, the development of faster and more revolutionary modes of transportation will have a significant impact on industrial development and our lives.
Recently, magnetic levitation trains have attracted a lot of attention. In addition, it is said that a means of transportation that can travel from Seoul to Busan in 16 minutes will be available. This uses hyperloop technology, which will have a tremendous impact on our society if it is properly realized. Let’s learn about the principles of these two means of transportation, magnetic levitation trains and hyperloops, which are currently in the spotlight.
Simply put, a magnetic levitation train is a train that uses magnetic force to levitate above the tracks and move. Two forces are required to move a magnetic levitation train: one to lift the train off the tracks and another to propel it in the desired direction. Let’s first look at the first of these two forces. There are two main methods for lifting a train off the tracks. There is the repulsion type, which uses the repulsive force between the poles of magnets, and the attraction type, which uses the attractive force between magnets and magnetic materials. The superconducting attraction type is suitable for high-speed travel, as it lifts the train about 10 cm into the air using the repulsive force between the poles of magnets. The superconducting attraction system uses a ∩-shaped electromagnet that wraps around the rails, and the attraction force varies depending on the distance between the electromagnet and the rails, allowing the train to maintain a constant height above the rails. This system is suitable for low-speed travel. The repulsion system can be used for high-speed travel, but because high speeds are difficult to control, the attraction system is often used instead. Currently, the attraction system is used in Germany, while the repulsion system is used in Japan.
Second, linear motors are used to move the train in the desired direction. These are linear versions of the circular coils found in conventional motors. Changing the direction of the current flowing through the coils changes the magnetic field, causing the force between the train and the track to periodically change between attraction and repulsion. Therefore, by adjusting the frequency of the alternating current flowing through the coils according to the speed of the train, it is possible to apply a force in the direction of travel to the train continuously.
Maglev trains are currently in operation based on this principle. Hyperloop is a more advanced form of maglev train, combining the principles of maglev trains with air pressure technology. The combination of these two technologies enables Hyperloop to reach incredible speeds of 1,200 km/h. The core principle of this technology is to minimize air resistance and friction by running in a vacuum tube.
Just as the magnetic levitation train mentioned above uses magnetic force to levitate the train above the track and maintain high speeds without friction, the Hyperloop also uses a method of slightly lifting the train off the ground to reduce friction.
More specifically, Hyperloop uses two technologies to reduce resistance. The first is vacuum magnetic levitation technology, which keeps the tube in a near-vacuum state so that the train can move using only magnetic force. The second technology is to push the vehicle forward using strong air pressure. Although Hyperloop may look similar to existing trains, there is a big difference in how it works. Hyperloop uses magnetic fields to generate propulsion and reduces friction by injecting air into the floor. The power required for this is supplied by solar panels installed on the vacuum tube. The ground tube through which the train passes is supported by earthquake-resistant pillars spaced 30 meters apart to withstand the speed of the train, ensuring stability.
Currently, commercialization of Hyperloop is underway in South Korea, but it has not yet been fully realized. The Korea Railroad Research Institute (KRRI) has successfully tested a “HyperTube” train based on Hyperloop technology at speeds exceeding 1,000 km/h. The train aims to reduce the travel time between Seoul and Busan to 30 minutes. Hyperloop technology has been demonstrated in various ways, with the world’s first full-scale hyperloop system near Las Vegas, Nevada, USA, completing more than 400 tests on a 500-meter test track. The technology has been made open source, creating opportunities for various experts and entrepreneurs to develop the technology together. Hyperloop is cheaper, more convenient, and faster than existing high-speed railways, and is not affected by external factors such as weather. In particular, it is attracting attention for its ability to solve energy problems as it can generate its own power using solar energy. However, there are still many technological challenges to overcome. Efforts must be made to develop high-efficiency air compressors that can lift heavy trains and enable them to travel at high speeds, as well as technologies to control and maintain balance during high-speed operation.
By solving these challenges one by one, we will soon be living in a new era. Looking back on the history of transportation, the introduction of new technologies has always brought about innovations in our lives. Now, the moment is approaching when advanced technologies such as magnetic levitation trains and hyperloops will once again dramatically change our lives. With high expectations for the new possibilities that these changes will bring, we must continue our research and development for a better future.
