Hunting stability analysis of high-speed train bogie under the frame lateral vibration active control

ABSTRACT

In this paper, we study a multi-objective optimal design of three different frame vibration control configurations and compare their performances in improving the lateral stability of a high-speed train bogie. The existence of the time-delay in the control system and its impact on the bogie hunting stability are also investigated. The continuous time approximation method is used to approximate the time-delay system dynamics and then the root locus curves of the system before and after applying control are depicted. The analysis results show that the three control cases could improve the bogie hunting stability effectively. But the root locus of low- frequency hunting mode of bogie which determinates the system critical speed is different, thus affecting the system stability with the increasing of speed. Based on the stability analysis at different bogie dynamics parameters, the robustness of the control case (1) is the strongest. However, the case (2) is more suitable for the dynamic performance requirements of bogie. For the case (1), the time-delay over 10 ms may lead to instability of the control system which will affect the bogie hunting stability seriously. For the case (2) and (3), the increasing time-delay reduces the hunting stability gradually over the high-speed range. At a certain speed, such as 200 km/h, an appropriate time-delay is favourable to the bogie hunting stability. The mechanism is proposed according to the root locus analysis of time-delay system. At last, the nonlinear bifurcation characteristics of the bogie control system are studied by the numerical integration methods to verify the effects of these active control configurations and the delay on the bogie hunting stability.

KEYWORDS:

• High-speed bogie
• hunting stability
• active control
• time-delay
• multi-objective optimisation
• finite dimensional state space approximation

Acknowledgements

In addition, the first author would like to thank the China Scholarship Council (CSC) for sponsoring his study in USA.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The material in this paper is based on work supported by grants (51675443, 11172197, 11332008 and 11572215) from the National Natural Science Foundation of China, and a Key Laboratory grant (Nos. 2015TPL_T10, 2017TPL_T02) of the Independent Research and Development Projects.