Transrapid Operation Control System (OCS)
Source: Transrapid International USA
The Transrapid Maglev System utilizes an automatic communication, command, and control system. The Transrapid Operation Control System (OCS) is a radio-based, decentralized system that is designed to be technically safe at all times and under all foreseeable conditions. This paper provides an overview of the Transrapid OCS, its functions and components as it is currently designed and configured in Germany.
All of the equipment and systems described in this report have been built, installed at the Transrapid Test Facility in northwestern Germany, extensively tested, and subsequently approved for use in application projects.
The Transrapid Test Facility in Lathen, Germany includes a test center, 31.5 km of single track elevated and at-grade guideway, three power substations, and an automatic operation control system. The Test Facility has been in operation since 1984 and a total of over 700,000 km of operation has been accumulated on the three maglev vehicles, TR06, TR07, and the current revenue prototype,TR08.
In order to be able to make full use of the operational and technical capacity of the Transrapid Maglev System at high speeds, an intelligent operation control system is used. Above all, this system makes sure that all the important processes of the normal operation take place automatically, without need for a driver, and within the responsibility of the technical safeguarding system. Operating personnel have no safety responsibility for the driving operation during scheduled passenger transport.
As a rule, the trains run as units of fixed lengths; coupling of two trains is not planned. The operation processes are started automatically in accordance with a schedule stored in the operation control system. Even if there are deviations from the set schedule, the system can automatically activate measures to return the trains affected (including following trains) to scheduled operation. These measures include variation of the operational route speed or shortening or prolongation of stop periods in the stations.
Only in isolated cases and irregularities (in particular service operations, serious
deviations from the schedule, malfunctioning due to external influences) are the processes
initiated by actions of the station master in the control center (CC). Therefore, it is
planned to permanently man the CC however, scheduled journeys will only be
monitored. Operating personnel are employed in the stations and vehicles for passenger
service and will only be brought in for operational jobs in case of malfunctions and in
emergencies. Safety responsibility will always remain with the technical system.
Safegarding of Scheduled Operation
The safety of the scheduled operation is guaranteed by a technically safe system, designated the operation control system, or OCS.
All operation control functions with safety responsibility are realized using safe and fail-safe microcomputers of type SIMISTM in a 2 out of 3 arrangement. Computers of this design consist of three independent computer channels with identical cores that work with synchronous cycles and commands. Process messages are read into all three channels and processed in parallel. Process-releasing commands become effective only if the results are identical. In this way, functional deviations can be detected by comparing the active programs online. Hidden failures in the SIMIS are detected by test programs running in the background. The safety function is fulfilled if two of the three channels yield the same results.
To safeguard the scheduled operation, the route is divided in individual safeguarding segments, the lengths of which are determined in accordance with the operation program and the propulsion configuration of a project. The switches and the facilities of the Transrapid Maglev System installed along the guideway (stations, parking, and maintenance facilities) in such a safety-related segment are included in the technical safeguarding where this is necessary to monitor the clearance envelope and to protect personnel and passengers. The locations of all vehicles are constantly followed and managed in the operation control system.
An on-board operation control system in the vehicle controls and monitors all the on-board systems relevant to safety and monitors the traveling motions. To do this, process data such as vehicle location and speed are permanently determined and compared to the admissible limiting values. The limiting values of the speed depend on the vehicle, direction of motion, and route alignment. For example, if the limits of the local speed range permitted are violated due to a malfunction of Transrapid Maglev System components, controlled automatic application of the vehicles auxiliary brakes is initiated. This either returns the train to the set speed or, in the event of a lasting malfunction, stops the train at the next stopping area defined.
Basic Concept and System Structure
The control system comprises the technical equipment for Transrapid Maglev System operation management, i.e. the functional units for planning, job planning, control, and safeguarding of the scheduled operation as well as the functional units for monitoring and control of the infrastructure. The system components are classified in accordance with the following three-level hierarchy (see Illustration 1).
1 Central equipment and functions, combined in a control center.
2 Decentralized equipment and functions, mainly located in the substations.
3 Mobile equipment and functions, installed in the vehicles, and safety modules and functions, located in operation buildings and switching stations along the route.
Connection and data transmission between the levels of the control system is realized by means of line-wide optical-fiber networks (WAN = wide area network). Connection to the vehicles is provided by the Transrapid Maglev System-specific 38 GHz radio transmission system.
Usually, no separate buildings are constructed for the equipment of the control system. The spaces and rooms required are integrated in the buildings for the substations, the guideway (e.g. guideway switch electrical buildings), the control center, the maintenance facilities, and the stations.
Last modified: June 19, 2002