Optimum Design of a High Functional Buffer for Railway Vehicles

2nd Report, Optimization of Structure and Proposal of Controller Design Methodology

Abstract

In the previous report, a new hydraulic draft gear, which had a function of controlling the coupler force, was discussed. The device introduced in the report aimed at lowering the coupler force acting between the failed and the relief Shinkansen train set. The results of excitation test on a prototype device based on analytically obtained specifications showed poor tracking performance of the hydraulic cylinder during return stroke while an increase in residual deviation when increasing the operation speed. In this paper, a hydraulic buffer resolving these problems is developed. The results of an excitation test that confirms its performance are described. The device, which arranges a hydraulic cylinder in the form of no rubber pad, adopts a piston return mechanism with pre-pressurization in the hydraulic circuit to improve the tracking performance. The coupler force is controlled by a PID controller to lower the deviation and improve the performance. An optimization methodology based on a non-linear model is proposed for the design of controller. The methodology is verified experimentally with a prototype performance.