Taipei Rapid Transit System Extension
Eric Lin, Senior Signalling Engineer at the Taipei Rapid Transit System, provides the first in a series of global case studies, detailing the signalling, telecommunications and infrastructure upgrades that are proposed and currently underway in the country.
The Department of Rapid Transit Systems (DORTS) was established in 1987, with the responsibility of planning, designing and constructing the rapid transit system in the Taipei Area. The current Taipei MRT Network is made up of a number of L-shaped lines, which are supplemented by circular lines, to provide access to surrounding satellite cities.
The DORTS are currently leading an extensive infrastructure expansion project, which will greatly increase the already substantial metro system. At present there is a total of 114.6 km of track, with 101 stations. In 2012 passenger volume increased to more than 1.7 million trips per day.
At present, 52.1 km of new routes are currently under construction, as well as 52.1 km of track. In the future this will be further expanded to create a network of 270 km, with passenger volume expected to increase to more than 3.6 million trips per day, according to Mr. Lin’s predictions.
The Wenhu Line currently operates a CBTC system that allows for a system headway of 72 seconds and fully unattended train operations. The system features ATS, ATO and ATP systems, and the reduced headways and lower operating costs means that the DORT will continue to expand the fleet of vehicles over the coming years.
As part of the MRT expansion, 8 new lines are currently under construction, featuring a total of 50.5 km of track and 44 stations. The Xinyu line will be completed shortly, while the Songshan line and the Tucheng Line Extension are also expected to be in commercial operation by the end of the year.
Over the next 5 years, the MRT will put into operation CBTC, Unattended Train Operation systems, on the Taichung Line, the Wanda Line and Phase 1 of the Circle Line. The Wanda Line signalling contractor is scheduled to be announced in 2013, and the route will also feature ATS, ATO and ATP technology. The line will also operate 19 new trains and will include a primary OCC system in depot, with a Simplified Redundant OCC in station.
The Wenhu line will operate at 30 km per hour, while the Circle and Tichung lines will operate at 35km per hour. The headways will be 72 seconds for Wenhu and 90 for Circle and Tichung.
Eric Lin explained that the CBTC system was chosen, as it provided a number of key benefits. These include;
1. Lower cost, less space, less maintenance
This is the result of the lower amount of trackside and SER equipment and devices necessary for CBTC operation.
2. Speed Change
The dynamic speeds of the CBTC system can provide a smoother and more gentle rider experience.
3. Minimum Headway
Track side equipment and variable train frequency is very important during rush hour.
4. Easy to retrofit
CBTC is the only existing signalling system to have a minimal impact on revenue services, when switched to an upgraded system.
While Mr. Lin was generally very positive about the impact of CBTC, he did note a number of potential concerns for future operations. Due to budget constraints, lines are often built over several phases and this can create issues with hardware and software interface protocols as a result of intellectual property rights protection, during preparation for the next phase. Mr. Lin expressed his hope that the provision of IEEE technical standards will prove to be more binding and widely adopted.
Eric Lin also expressed concerns about potential interference problems, especially if the CBTC system uses the public frequency band.
Eric Lin concluded by noting that driverless systems are generally more reliable than manual operations and that the CBTC has an advantage in regards to increased capacity, reduced headways and less wayside equipment. He expects that in the future public transport will increasingly popular and he urged operators and suppliers to work closely to ensure effective working relationships and ultimately improved passenger services.