Bogie assembly, rail vehicle and rail system

The invention discloses a bogie assembly of a rail vehicle, the rail vehicle and a rail system, the bogie assembly of the rail vehicle comprises a bogie, and the bogie comprises a mounting frame; and the locking mechanism is mounted on the mounting frame, and the locking mechanism is used for receiving an external signal and locking or unlocking the bogie according to the external signal. By mounting the locking mechanism on the mounting rack of the bogie, the locking mechanism can selectively lock the guide frame under the condition of receiving an external signal, so that the problem that the rail vehicle is excited by the guide surface of the rail beam to cause the traveling wheels to swing back and forth can be avoided, the bogie can be locked when the rail vehicle goes straight, and the service life of the bogie is prolonged. And the stability and smoothness of the rail vehicle during straight running are ensured. Moreover, when the railway vehicle turns, the locking mechanism can receive the external signal and unlock the bogie according to the external signal, so that the railway vehicle can better turn.