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Magnetic brake is a kind of non-adhesive brake technology for train. Magnetic brake is an electromagnet in essence, which is installed under the train bogie and mainly used for emergency brake of train. When train in normal running, the magnetic brake is in a static state without brake. When the brake command is given, the magnet energizes, at which point the brake device establishes an initial magnetic field that generates attraction force toward the track. This attraction overcomes the pull of the suspension system and pulls the brake onto the track. When the braking device and the track are fully attracted, the interaction between the two forces reaches the maximum, and friction with the rail, so as to brake the running train.