The Development of Advanced High Speed Vehicles in Sweden

Abstract

The rail network of Sweden is characterized by frequent curves, which limit the speed of conventional rolling stock to moderate levels. Speed of travel is, however, probably the most important factor in competition between different modes of transport, both now and in the future. For economic reasons the existing track must be used, with minimum modifications. Effort in Sweden has therefore been concentrated on the development of a new technology, making it possible to run at 35–60 per cent higher speeds on existing track. At these higher speeds comfort levels and track forces must not be worse than for current rolling stock running at present speeds on the Swedish main line track. In order to satisfy these requirements, future vehicles must be equipped with car body tilting, and must also exhibit food dynamic interaction with irregular track. Swedish State Railways (SJ) and ASEA have jointly developed and tested a new concept, including hydraulic or pneumatic car body tilting and radial steering bogies. These bogies allow for high speed through curves without excessive lateral forces and the associated wear on wheels and rails. In this bogie it has been possible to optimize primary suspension and damping parameters so as to maintain stability without hunting at speeds of up to at least 200 km/h. An experimental train set, type X15, was the subject of extensive tests during the period 1975–82. The design of the bogies and car body tilting systems has been supported by computer simulation programs. New methods of analysis have been developed and validated as an integral part of the development project. The simulation technique has proved to be very useful and accurate in the prediction of vehicle dynamic behaviour. Also some tests of passengers' opinions on comfort in tilting trains have been carried out.

Influence of different conditions for tilt compensation on symptoms of motion sickness in tilting trains

“…In regard to railways, passenger ride comfort and discomfort on curves have attracted much research [2,6,9,10,16,20,33,34], but concerning motion sickness, a good understanding of the problem is still needed [1 1,12,27,36]. A 1.00% compensation has been found to be provocative for motion sickness in the Advanced Passenger Train test in 1984 [7], and a recommendation for a tilt compensation of two thirds (67%) has been given [16,17].…”

Simulation of combined body tilt system of high-speed railway rolling stock

“…В якості приводу систем нахилу кузовів цих поїздів використовуються гідравлічні [20], пневматичні [18] і електромеханічні системи [2,3,14,15], або пасивна система нахилу, що приводиться в дію за рахунок відцентрових сил [8,21]. Гідравлічна система залежить від погодних умов, екологічно недосконала через можливість витоків, її конструкція, експлуатація та ремонт відносно складні [2]; пневматична система не забезпечує належного швидкодії [2,22]; електромеханічна система, будучи найбільш перспективною [14,15], не забезпечує належного рівня безпеки руху через відсутність самоповороту механізму нахилу, у разі відмови застосовуваних ротативних електромеханічних перетворювачів спільно з редуктором [23,24].…”

Cultural differences in conceptual models of ride comfort for high‐speed trains

“…Independent from the ORE and ERRI, the British and Swedish railroads have undertaken research on ride comfort responses, particularly on ride comfort disturbances from highspeed trains (Andersson & Nilstam, 1984). The Japanese have done extensive work on comfort and nausea for both very high-speed trains and tilting trains (Koyanagi, 1985;Suzuki, 1996).…”