Experimental study of bogie instability monitoring and suppression measures for high-speed EMUs

As the key part of the rail vehicle, the bogie’s dynamic performance directly affects the vehicle’s operating performance. A large number of bogie instability phenomena occur during the operation of high-speed Electric Multiple Units (EMUs), which has an important impact on the safety and passenger comfort of the high-speed EMUs. In this paper, through a combination of line tests and simulations to study bogie hunting, line tests are first conducted to test the vibration data and wheel wear evolution of the high-speed EMUs. The data was analyzed to find out the evolution of the bogie instability law of the high-speed EMUs. Then the vehicle dynamic model is established to find out the mechanism of the bogie instability, and finally bogie instability suppression measures are proposed. The results of the test data showed that the wheel wear, the frequency and the amplitude of bogie instability of motor car is greater than that of the trailer car, and the ride index is poorer. The ride indexes at the early and late stages after wheel re-profiling do not exceed 2.5. The equivalent conicity increase is the main cause of bogie instability, and the bogie instability can be effectively suppressed by wheel re-profiling, replacing the yaw damper, and the rail grinding.