Page 93 - 捷運技術 第35期

捷運技術半年刊 第 35 期 95 年 8 月 85

Each train has two sets of vehicle ATC（VATC）equipment so that redundancy is achieved
within each train. The train location is determined based on tachometer readings from wheel axles
or gears.
Due to tolerances in equipment and wheel diameter, positioning errors may accumulate.
Norming points are therefore located along the track to allow the vehicle to reposition itself
periodically. Each norming point is a passive tag that is energized and read by a transponder
interrogator mounted on the vehicle as the vehicle passes over.

The ATC components, both wayside and onboard are divided into two sub-systems, provided
below.

2.3.2.1 EBI Cab Automatic Train Protection（ATP）
The EBI Cab system is responsible for the safety aspects of the train control system. The
wayside component is referred to as a Region ATP）RATP)and the onboard component as Vehicle
ATP（VATP）. The VATP is responsible for the safe operation of the train including safe train
movement and occupancy generation.

In a CITYFLO 650 system, the ATP systems perform the safety critical tasks such as:
˙Train Occupancy Detection（RATP and VATP）
˙Safe Train Separation（RATP）
˙Roll-back Protection and Direction Control（VATP）

˙Overspeed Protection（VATP）
˙Propulsion and Braking Interlocks（VATP）
˙Parted-Train Protection（VATP）
˙Switch Interlocking Control（RATP）
˙Occupancy Generation（VATP）
˙Door Control Enabling and Interlocking（VATP）
˙Route setting and interlocking

Each Region ATP consists of an independent primary and backup system. Each primary and
backup ATP system interfaces with an independent regional ATO and base data radio. Each ATP
system contains dual-channel, check-redundant processors for safety. The functions of each ATP
system is identical, although the inactive ATP is restricted from exchanging data with the trainborne
ATCs and from performing device control until manual switchover occurs.

Manual switchover in the event of failure is provided through an ATS control screen at central.
All wayside device interfaces are brought back to redundant Region ATPs for vital control
from either the primary or the backup system. Either primary or backup can be in an “active” or
“standby” state depending upon which ATC has control of the system. Train control, train tracking,
and interlocking functions are implemented by the currently active ATC.
2.3.2.2 EBI Cruise Automatic Train Operation (ATO)

The EBI Cruise system is responsible for the “non-safety” operation of the train control system
within the CITYFLO 650. Similar to the ATP, the ATO system also has both the region and train
components - the Region ATO（RATO）and the train or Vehicle ATO（VATO）.
Each Region ATC has an independent ATO designated as Region ATO. The Region ATO
performs all non-vital functions related to directing train movement and station operation. In