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In railway signalling systems, trackside equipment and signalling devices are controlled by wayside object controllers (OC). With the application of radio communication to wirelessly transmit command control and signals, the cost of cabling and installation has been significantly reduced. However, for non-electrified regional lines in rural areas, dedicated cables are still installed along the track to drive the wayside object controllers, which increases both capital and operational costs. With the development of renewable energy sources (RES) and wayside energy storage systems (ESS), a concept of smart wayside object controllers (SWOC) is proposed, which are autonomous, off-grid and powered by local renewable energy sources to reduce the related costs. To assist future system development, this work develops methods to not only calculate power and energy demand for system configuration but also estimate the life cycle cost in long-term operation. A case study based on a railway test site in Sweden is performed. This study shows that it is sufficient to use 100% local renewable energy sources to power the SWOC, trackside equipment and signalling devices. Compared with the existing system, the SWOC shows a significant cost saving in long-term operation by removing cabling and installation, reducing trackside maintenance and replacing the power supply with renewable energy power sources for decarbonisation. Therefore, the SWOC shows its significant benefits over the existing system from both economical and environmental aspects. In the end, some suggestions for future development and implementation of SWOC are given.

Out-of-round (OOR) wheel often happens to trains, which can cause abnormal vibration. To develop effective countermeasures to minimize the abnormal vibration, it is necessary to study how the wheel OOR wear affects the vehicle vibration. This paper performs an experimental study on the abnormal vibration characteristics of metro trains with out-of-round wheels. The vibration characteristics is identified by the general survey of wheel roughness from special tests. The statistic wheel wear values of all the vehicles in an operating metro lines are studied to investigate the relationship between the wheel wear and the operating mileage. Several re-profiling strategies are implemented to eliminate the abnormal vibration caused by wheel OOR. The results show that the root cause of the abnormal vibration and deterioration of ride comfort is the car-body flexible resonance excited by the wheel OOR wear. Wheel re-profiling is the most effective measure for reducing the vehicle abnormal vibration. By re-profiling all the wheels of a tested metro vehicle, the ride comfort can be improved by 35% ∼ 40% and the axle-box acceleration can be reduced by 40%.

Improving energy efficiency and reducing CO2emissions are becoming very essential worldwide. To encourage the development and application of energy-efficient and low-emission technologies and to increase people's awareness of energy-saving, many energy labelling systems are developed and utilized in most countries. Since energy labelling systems have a significant impact, more and more sectors are developing their energy labelling systems to have their products included. Globally, the transport sector consumes a great proportion of energy and is responsible for considerable CO2emissions. Although rail vehicles have relatively high energy efficiency, a labelling system has not been developed in the railway sector, whereas other modes of transport have developed energy efficiency indicators or energy labelling systems. Therefore, it is necessary to develop an energy labelling system for rail vehicles to promote rail transport and develop the technology of rail vehicles. First, this paper gives a review of the existing energy labelling systems. Second, it summarizes the rail needs and rail stakeholders’ interests regarding energy efficiency and corresponding labelling. Last but not least, a proposal for an energy labelling system for rail vehicles is given.

Trains operating with several pantographs are used in Sweden and other countries. The more complex operational conditions, however, cause additional difficulties, i.e. low quality of current collection, increased mechanical wear and electromagnetic interference, due to the poor dynamic behaviour of the system. In order to address these problems, a three-dimensional model for the computational analysis of the interaction between catenary and pantograph is presented and validated in this paper, and the dynamic behaviour of the multi-pantograph system, based on Swedish soft pantograph/catenary systems, is analysed. Parametric studies are performed to investigate cases with different distances between pantographs and with up to three pantographs in use. The relationship between dynamic performance and other parameters, i.e. the number of pantographs in use, running speed and the position of the pantographs, is studied. The results show that an appropriate distance between pantographs and a given type of catenary allow operation on the existing infrastructure with up to three pantographs while maintaining an acceptable dynamic performance at the desired speed.

Powerful electric locomotives with high traction performance are foreseen to be used to boost the overall performance of freight transport. However, they would exert extra burden on the power supply system, so the power peak demand would be a bottleneck for future freight transport. To avoid large-scale modifications to the existing systems but ensure operational reliability, this study investigates the formation of power peaks and explores power peak shaving concepts to let the existing systems be more reliable and accommodate more freight traffic. Different from many previous studies which focus on energy saving, this study aims at lowering the power peak demand by “smart train operation”, i.e. altering the train speed profile without compromising running time. This study is mainly performed by simulation based on a standardized freight operation with full regenerative braking used. But this study also shows a real case study based on measurement data of power history from an onboard energy meter. The study shows the formation of power peaks in different conditions and suggests some possible measures to shave the power peak demand. The study also shows that there is a compromise between power peak shaving and energy saving, to which more attention is needed in future studies.