Electric traction systems overview of signalling and train control systems

This paper considers the events that brought about the signalling systems of today, the primary functions and technology of the signalling and the underlying design principles. It looks at the operation of the railway as a system and in particular at the role of train control systems. This includes the role of Automatic Train Protection (ATP) in a modern metro environment, the application of automatic train regulation, and automatically driven trains protected by a moving block, radio based, signalling system. The need for synergy between the designs of the rolling stock and signalling systems is demonstrated by a review of current practice, and a way forward towards a more systematic approach is outlined. The role of signalling in gathering and disseminating information and the potential for integrated customer information management, the needs for management information and the potential benefits of improved real time maintenance information are outlined. Whilst written primarily from the point of view of a rapid transit railway signalling engineer the author makes use of some passing acquaintance with bigger trains and other technologies.