How can you stop a maglev train

The third set of loops is a propulsion system run by alternating current power. Here, both magnetic attraction and repulsion are used to move the train car along the guideway. Imagine the box with four magnets -- one on each corner. The front corners have magnets with north poles facing out, and the back corners have magnets with south poles outward.

Electrifying the propulsion loops generates magnetic fields that both pull the train forward from the front and push it forward from behind. This floating magnet design creates a smooth trip. Even though the train can travel up to miles per hour, a rider experiences less turbulence than on traditional steel wheel trains because the only source of friction is air.

Another big benefit is safety. The further a Maglev train gets from its normal position between the guideway walls, the stronger the magnetic force pushing it back into place becomes.

When the train departs from the station, the energy for levitation and vehicle-borne equipment is supplied by the collectors that are connected to PR. In order to run to the next ASA, all the vehicle-borne batteries have to be evaluated. The operation control strategy is to satisfy the minimum capacity requirement for levitation and emergency braking at least once.

Once the train speed is lower than the minimum levitation limit, PPS will be shut off, making the train float to the nearest ASA in levitation state. In the pull-in deceleration area, the operation control strategy is to use kinetic and potential energy to run into the station, as shown in Figure 6. In such case, the operation control strategy is to cut off the power for other train-borne equipment to guarantee the energy supply for levitation and emergency braking.

When connected trains run with the same direction in the same line, the location and speed of the leading train can affect the following train according to the mobile blocking principle. In this case, the leading train is treated as a mobile obstacle for the following train. As shown in Figure 7 , to guarantee the safety of the following operation, together with the mobile blocking method and the leading train state, the operation control strategy for the following train is to formulate a speed limit i.

Normally, the following train runs behind the leading one for more than the safety distance. If the leading train decelerates or performs an emergency braking, the following one performs corresponding strategy to prevent it from crashing into the leading one.

In the extreme case, when the leading train stops on the line for some reasons, the operation control strategy for the following train is to stop in the ASA that is behind the leading train for at least one safe ASA. As is shown in Figure 8 , during the following operation, if the train-borne batteries of the leading train break down to bring an emergency braking, the following train can obtain the related data through RCS.

In this case, two operation control strategies can be formulated to save battery energy of the following train: if the following interval is long enough and the following train cannot stop in the next ASA because of high speed, the following train can accelerate to the maximum speed, coast for a specific distance, and then brake to stop in the ASA that is behind the leading train see curve B ; if the current speed is relatively low, the following train is braked to stop in the next ASA see curve A.

In this section, a simulation is carried out and an experiment is performed to verify the effectiveness of the proposed operation control strategy and illustrate the applicability of the obtained results. The map of the scenario and the line sketch are shown in Figures 9 and 10 ; the parameters of the maglev train and the line are described Table 8.

The resistance and corresponding deceleration of the train at different speeds are shown in Figure The remaining capacity of the vehicle-borne battery is a key factor that affects the operation control strategy formulating.

The speed-distance and energy-distance curves under the emergency braking and intrinsic resistance braking are shown in Figures 12 and From Figure 12 , the minimum running point and the related energy for levitation and other vehicle-borne equipment can be obtained. Meanwhile, the maximum running speed and the corresponding energy can be obtained from Figure During the operation control strategy formulating, any ASA within these two points can be chosen to stop the train.

During the running, if a vehicle-borne battery related emergency happens, based on our proposed operation control strategy, the train can run for a given distance at the constant speed and then the emergency braking is performed to stop the train quickly to consume the battery energy as little as possible.

From Figure 14 , it can be seen that the train consumes less vehicle-borne battery energy and total running time is shorter at a higher initial speed. From 11 and 12 , the total energy consumption is 4. As is shown in Figure 15 , during the following operation for the connected trains, if the leading train performs an emergency or decelerates for some reasons, the following train should adjust the operation strategy to prevent it from crashing. Thus, the safety of the following operation for the connected trains can be guaranteed.

For the connected trains, in case of shutting-off PPS for the following train, the operation control strategy for the following train is to evaluate whether the following interval between the two trains is larger than the floating distance and the train-borne battery capacity is enough to supply the levitation for the floating.

If true, the following train can float to the next ASA. Because the following interval is larger than the floating distance, the following train can float to the ASA between the train location and the farthest floating point.

In this paper, considering the vehicle-borne battery condition monitoring, an operation control strategy is proposed to guarantee the operation safety of the connected maglev trains. The following train formulates the operation control strategy in real-time according to train-borne battery conditions and the operation state of the leading train. The simulation and experiment are given to demonstrate the effectiveness of the proposed strategy. Further investigations could be concerned with operation control strategy formulation for the connected trains considering the state of other vehicle-borne equipment and combining these constraints together.

The authors declare that there are no conflicts of interest regarding the publication of this paper. This is an open access article distributed under the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Article of the Year Award: Outstanding research contributions of , as selected by our Chief Editors. Read the winning articles.

Journal overview. Special Issues. Academic Editor: Cesar Briso-Rodriguez. Received 08 Dec Accepted 07 Mar Published 12 Apr Abstract Vehicle-borne battery condition is an important factor affecting the efficiency of the maglev train operation and other connected ones. Introduction After the introduction of high-speed maglev train Transrapid into Shanghai in and with the operations of both Airport Line of Changsha in and S1 Line of Beijing in , maglev transportation system has received more and more attention in China [ 1 , 2 ].

The main contributions of this paper are as follows. Dynamic Analysis of the Maglev Train Generally, the maglev train can be regarded as a rigid body when we study the operation control strategy.

The additional gradient resistance is In addition to the above-mentioned resistances, the curve line adds another additional curve resistance that can be described as follows: The train-borne equipment energy is where is levitation energy, is emergency braking energy, and is vehicle-borne equipment consumption energy.

The train levitation power is Although the whole deceleration process of the train is variable, the deceleration in a short differential time within can be assumed to remain constant. Therefore, the running distance can be obtained by 3. Vehicle-Borne Battery Condition Sensor Network for Connected Maglev Trains In this section, the impact of battery conditions on the operation and the monitored battery parameters are analyzed briefly. Figure 1. Figure 2. Table 1.

Table 2. Remaining capacity Condition Not enough to provide energy for levitation and emergency braking Battery exhausted Enough to provide energy for levitation and emergency braking, but cannot provide extra energy for vehicle-borne equipment No enough energy Meets all the vehicle energy requirements Sufficient electricity.

Table 3. Table 4. Figure 3. An IoT based sensor network scheme for the maglev train. Figure 4. Figure 5. If the temperature continues to rise but does not reach the limit of combustion, all passengers get off after the train stops. Table 5. Remaining capacity Operation control strategies Not enough to provide energy for levitation and emergency braking Turn off air conditioners and other vehicle-borne equipment. The train is not allowed to run unless the required capacity is charged.

Enough to provide energy for levitation and emergency braking, but cannot provide enough energy for vehicle-borne equipment Turn off the vehicle-borne equipment to keep safe levitation to the next ASA for recharging. Meets all the vehicle energy requirements Run normally. Table 6. Table 7. Figure 6. Figure 7. Figure 8. Parameters Numerical value Total weight of single full load vehicle, t 62 terminal Table 8.

Figure 9. Figure Speed-distance and energy-distance curves of the train under emergency braking. Speed-distance and energy-distance of a train under intrinsic resistance. The running time and the energy consumption versus the initial speed. The floating running for the following train without PPS. Regenerative braking is normally used for deceleration, but if it becomes unavailable, the Superconducting maglev also has wheel disk brakes and aerodynamic brakes.

On the Yamanashi Maglev Line, the braking system has been repeatedly examined on tough scenarios, e. This system uses linear motors as generators to decelerate the train. This system uses disk braking equipment fitted to wheels to mechanically decelerate the train. This system extends air drag panels from vehicle to use air resistance for deceleration. It gives a particularly significant deceleration effect when traveling at high speed.

Even if the power goes out, levitation forces keeps the train in the air while it is traveling at high speed. The vehicle comes safely to a stop rather than suddenly falling onto the track. Even if one substation suffers an outage, electricity can be fed from an adjacent substation, providing a high degree of redundancy. Even if one substation suffers an outage, electricity can be fed from an adjacent substation to keep the train in operation.