Modular, redundant UPS systems ensure the safe and continuous flow of rail traffic. Optimized investment in control and signaling systems maximizes the use of rail networks, and lowers the cost of new infrastructure and railway lines.
UPS systems ensure rail networks deliver efficient, punctual, secure and reliable service, providing uptimes in the range of 99.9999 percent.
The highest uptime capacity is essential because rail infrastructure is exploited 24 hours per day, 365 days a year, and high-speed rail traffic must be able to move in different directions without creating disruptions. This makes reliable signaling systems and accurate transit management key factors in the profitability of a railway system. ABB’s UPS systems for rail are designed to reliably protect the rail network’s power supplies, often from two redundant sources – the public power network and a private railway power supply.
A unique feature of ABB UPS systems is the interchangeability of modules, which radically reduces spare part count and simplifies servicing. A defective UPS module can be onlineswapped (removed or inserted) in 20 minutes, without risk to the critical load.
This directly addresses continuous uptime requirements, significantly reduces MTTR (mean time to repair), reduces inventory levels of specialist spare parts, and simplifies system upgrades. The approach also pays off in terms of serviceability and availability – online swapping means there is no downtime and service personnel do not need special skills to replace or install modules.
Spares can be held on-site or at a nearby service center, improving availability and reducing cost as service engineers spend less time on-site, the risk of power loss is minimized and inventory levels of specialist spare parts are reduced.
ETCS (European Train Control System) is a signaling, control and train protection system set up to replace incompatible safety systems in European railways, especially on high-speed lines. ETCS power supplies are typically backed up by a diesel electric generator, which has a significant impact on the installation cost of the entire system, and, because it takes up considerable space, on system power density.
ABB’s solution not only aims to remove the backup diesel electric generator (and associated greenhouse emissions and noise), but to also increase the level of redundancy by adding a battery pack.
Where an independent second mains network is available, it can also be used in the backup power scheme. An ABB dual-frequency UPS converter makes it possible to harness the power networks of different frequencies, so the load can utilize either, or both, as appropriate. If a fault develops in one, the dual-frequency UPS feeds the critical load through the other. In the event of a fault in both independent networks, a third energy storage option – the UPS battery pack – would provide power needed, for example, by a control system like ETCS, ensuring zero downtime for the entire system.