TheChinese Train Control System (CTCS,Chinese:中国列车控制系统) is a train control system used onrailway lines inPeople's Republic of China. CTCS is similar to theEuropean Train Control System (ETCS).[1]
It has two subsystems: ground subsystem and onboard subsystem. The ground subsystem may includebalise,track circuit, radio communication network (GSM-R), and Radio Block Center (RBC). The onboard subsystem includes onboard computer and communication module.
There are 5 different levels (Level 0 to Level 4). Levels 2, 3, and 4 are back-compatible with lower levels.
For railway lines where operational speeds are below 120 km/h (75 mph):
Level 0 is used on lines with conventional trackside signalling. Train drivers follow trackside signals primarily, with cab signals as back-up. UCS receives trainfixed block occupation signals from track circuits and is shown as cab signals using digital signal processes. TOSU/LKJ is used to supervise speed limits and can only advise train drivers on braking curves. The drivers are mainly responsible for maintaining train speed protection.[3][4]
For railway lines where operational speeds are below 160 km/h (99 mph):
Balises are installed in addition to track circuits.Automatic train protection (ATP) is enabled on CTCS level 1.[3][4] Drivers use cab signals as primary signals.[3] Train circuits are responsible for detecting track occupancy and integrity. Temporary speed restrictions, train positions and track data are provided intermittently.
Forhigh-speed railways where operational speeds are below 250 km/h (160 mph):
The track circuit is used both for train occupation detection and movement authorization, its architecture is similar toTVM-300.[4] Balises and track circuit serves to provide intermittent trackside information andautomatic train protection (ATP) to cab equipment. Trackside signalling is not mandatory and can be replaced with cab signalling using DMI. LKJ can be equipped as redundancy on CTCS-0 lines. Minimum headways on CTCS-2 is 180 seconds.[4]
This system is compatible withETCS-1.
Forhigh-speed railway of above 250 km/h (160 mph):[4]
CTCS-3 introducesGSM-R radio forbidirectional data transmission.[6][2] Track circuits are used as a redundant system to CTCS-3. Train positions can be accurately calculated using balises and onboardodometers which are transmitted to Radio Block Centres (RBCs).[4] Authorisation of train movement is created by RBCs and transmitted onto on-board cab equipment using GSM-R.[3][4] Using both trackside equipment and onboard equipment, ATP can be achieved. Trackside signalling is not mandatory and can be replaced with cab signalling using DMI. It is considered to be a "quasi-moving-block" system.[3][4]
This is currently in use for all of the 200–250 km/h (125–155 mph) lines onChina's high-speed railway system, with a backup system of CTCS-2. CTCS-3 is equivalent toETCS-2.[3][4]
CTCS-4 would featuremoving blocks, self-train-integrity-check, and the complete elimination oftrack circuits, which would significantly reduce the amount of conventional track signalling equipment needed. Train integrity would be completely detected entirely through CTCS-3. Data transmission would be performed onGSM-R orLTE-M. Trackside signalling is not mandatory and can be replaced with cab signalling using DMI.[3][4]
Currently, Level 4 is not in use on any tracks and exists only as a conceptual system equivalent toETCS-3. It is being developed and defined by signalling manufacturers in China.[3][4]