The critical functions concerning availability are:
1. Support and guidance of a cabin
2. Motoring a cabin
Topic 1: It is assumed that the cabin has
the following architecture: Four mutually independent air gap control systems.
Levitation and guidance is still possible if at least two system are operational.
MTTF (Mean Time to Failure) for one of these systems is:
|total per system||
|per cabin (4 systems)||
Actions taken on failure are:
1. A cabin with one failed air gap control system must not enter commercial service.
2. On failure of an air gap control system during commercial service the cabin may finish its current trip.
3. On failure of a second air gap control system during commercial service the vehicle must exit at the next station, unload the road vehicle and be repaired.
Calculation of failure frequency for the
sample line Duisburg-Cologne according to Annex A10. Changeover rate be
|number of cabins||
|line exploitation (road vehicles per day)||
|averaged operational hours per cabin and day|
|at 40 km (total 16 min) averaged trip length||
|the total system has a failure of type 1 or 2 each||
|and a failure of type 3 each||
Concluding, no appreciable non-availability result by failure of the air-gap-control system.
For topic 2 it is assumed that the inverters
may be switched to three long stator sections each. On failure of a stator
supply system a neighbouring system takes over. MTTF of the long stator
On failure of three neighbouring supply
systems the motorising function of a long stator section fails only. In
this case the cabins may pass this motor section non motorised only. Delays
of typically a few seconds result. The line Duisburg-Cologne has approximately
10,000 motor sections. 4h averaged repair time.
|Frequency of an inverter failure: a failure each||
|Frequency of a failure of three neighbouring inverters: each||
No appreciable non-availability due to
failure of the stator power supply result.