Optimization of Spring Suspension Parameters and Evaluation of Dynamic Performance of a High-Speed Electric Train Car

Objective: implementation of the federal project for the development of high-speed railways requires the development of carriages that meet high dynamic performance requirements. Previously, spring suspension parameters for a high-speed electric train car on four single-axle bogies were determined based on lateral oscillations. The objective of this study is to optimize the spring suspension parameters for a spatial model of a carriage taking into account non-stationary random processes of vertical and horizontal oscillations of the car body and bogies, traction drives, and to perform a quantitative assessment of the car’s dynamic performance indicators. Methods: optimization of the spring suspension parameters was carried out using the convolution and Nelder-Mead methods. Dynamic performance indicators such as dynamic coefficients and total body accelerations at the “pivot” points were adopted as optimization criteria. Probabilistic methods were used to process the modeling results. Results: optimal values for the spring suspension parameters were obtained, which ensure carriage movement at speeds of up to 125 m/s (450 km/h). The features of determining the dynamic coefficient of the third stage of the spring suspension and ride comfort are considered. The paper presents graphs of two-dimensional spectral densities of deformations and forces in the third stage of the spring suspension, as well as lateral accelerations of the car body. A two-dimensional graph of the dynamic rigidity modulus of the third stage of the spring suspension is also presented. A quantitative assessment of the dynamic performance indicators of the optimized system and graphical dependences of these indicators on the vehicle speed are presented. It is established that the dependences of the dynamic performance indicators on the vehicle speed of the prospective bogie begin to decrease after reaching a maximum value, in contrast to the monotonically increasing dependences inherent in standard bogie designs. Practical importance: the results of this study are important for the development of high-speed railways and can be used in the development of design documentation for the bogie of a high-speed electric train.