The operation of high-speed trains at higher velocities leads to a sharp increase in kinetic energy, a rapid decrease in wheel-rail adhesion, and an elongation of braking distances, significantly reducing the efficiency of high-speed rail transportation and greatly increasing the risk of train collisions and other major accidents. Addressing the contradictory challenge of increasing train speed grades while maintaining constant braking distances under the existing high-speed rail signaling system is an urgent engineering problem in rail transit. Aerodynamic braking technology, originating from aircraft spoilers, is a novel braking technology that is gradually being applied to high-speed trains, characterized by its environmental friendliness, low cost, and significant braking effect. However, traditional aerodynamic braking technology suffers from strong plate interference. Therefore, this study focuses on the aerodynamic braking technology with blunting train streamlined sections, considering the impact of various working conditions such as braking plate application, relief, and failure on the aerodynamic characteristics of the train. Numerical simulations were conducted on three geometric structures of aerodynamic braking trains using the Reynolds-averaged method and the SST k-ω turbulence model. The results indicate that the installation of aerodynamic braking devices leads to more distinct surface pressure distribution characteristics, induces strong separated airflow phenomena, and alters the aerodynamic performance of the train, with increases in aerodynamic drag, lateral force, and lift, although the changes in lateral force and lift are relatively minor. The failure of braking plates affects the aerodynamic performance of the train, with minor changes in aerodynamic drag and certain changes in lateral force and lift, but the values remain within a certain range. Compared to the original high-speed train, the drag increase effect of the aerodynamic braking structure used in this study is approximately 252.91%, and the drag increase effect under braking plate failure conditions still reaches 249.52% of the original high-speed train, demonstrating the reliability of the studied aerodynamic braking devices. This provides support for the safe and reliable braking of higher-speed trains and can cope with sudden device failure situations, fully ensuring the life safety of passengers on higher-speed trains.