A Full-Scale Experimental Investigation on Ride Comfort and Rolling Motion of High-Speed Train Equipped With MR Dampers

Y. Q. Ni,S. M. Sajjadi Alehashem,X. Z. Liu

doi:10.1109/access.2021.3106953

Abstract

Achieving higher operation speeds safely and comfortably is yet a significant challenge in the railway industry. The rail irregularities and wheel-rail interactions in a train running at high speeds may result in large-amplitude vibration in the train’s car body and affect passengers by reducing ride comfort. The train suspension systems have a crucial role in reducing the vibration and improving ride comfort to an acceptable level. In this context, an exclusive semi-active magneto-rheological (MR) damper with a favorable dynamic range was designed and fabricated. The MR dampers were installed in a high-speed train’s secondary lateral suspension system in replacement of original passive hydraulic dampers, with intent to mitigate vibration of the car body and keep the ride comfort in a proper level at low and high running speeds. A unique full-scale experimental investigation on the high-speed train equipped with MR dampers was carried out to evaluate the MR damper functionality in a real operating situation. The full-scale roller experiments were conducted in a vast range of speeds from 80 to 350 km/hr. At each speed, different currents were applied to the MR dampers. The car body dynamic responses were collected to evaluate the ride quality of the train. Ride comfort indices under various train operating conditions are calculated through Sperling and UIC513 rules. This study reveals that the designed MR dampers effectively reduce the car body’s rolling motion. According to Sperling ride comfort index, the car body vibration was “clearly noticeable” at some running speeds when adopting the MR dampers, but it was not unpleasant. Besides, a “very good comfort” was achieved according to the UIC513 criterion. Also, no train instability was whatsoever observed at high speeds. This experimental investigation bears out the capability of the devised MR damper to achieve desirable ride comfort under high running speeds.

Highlights

The suspension systems used in railway vehicles are categorized as passive, active, and semi-active [1]
PREPARATION OF EXPERIMENT A unique, comprehensive full-scale roller test was conducted on the high-speed train model CRH3, which was equipped with the devised MR dampers, to evaluate the ride quality and rolling motion of the train car body
A unique and comprehensive full-scale roller test was carried out on the high-speed train model CRH3 with the intent of investigating the ride quality of the train equipped with MR dampers

Summary

INTRODUCTION

The suspension systems used in railway vehicles are categorized as passive, active, and semi-active [1]. 48 train operating conditions were tested with the corresponding car body dynamic behaviors measured with accelerometers and displacement sensors. Both ride comfort and rolling motion of the carriage were evaluated. This experimental investigation proves desired efficiency of the devised MR dampers and pushes forward the feasibility of using MR dampers in high-speed trains suspension systems. PREPARATION OF EXPERIMENT A unique, comprehensive full-scale roller test was conducted on the high-speed train model CRH3, which was equipped with the devised MR dampers, to evaluate the ride quality and rolling motion of the train car body.

Electric current input to MR dampers

Ride comfort evaluation very good good moderate poor very poor

Displacement sensor

Crest Factor of Displacement Signal

CONCLUSIONS