Intelligent rail technology for rail brakes
New and very low-maintenance technology for rail brakes in marshalling yards facilitates the automatic assembly of freight trains
Maneuvering without rail brakes is not possible
Freight trains are assembled in special marshalling yards. Steered by points, the wagons automatically roll from the shunting hump exactly to the target track, on which the train for a particular destination is put together. At the same time the wagons must be slowed down in a controlled way before they reach the end of the train they are to join. After all, the cargo must not get damaged during this maneuvering. What at first sounds very simple, is actually a very complicated process. Because with mixed trains wagons of various kinds are coupled together. Here, for example, the number of axles, center-distance, running characteristics, tonnage and length of the wagons vary. Also, wind direction and wind speed have a significant impact on speed and therefore braking behavior of each wagon.
Extensive data recording before and during the rolling procedure
Even before the freight wagons are sent onto the shunting hump, as well as while rolling down, this data must be collected from numerous sensors. From this, the necessary deceleration is calculated in the rail brake. Up to now this deceleration has been done by hydraulically, and pneumatically activated brake blocks in the track, pressing on the rims of the wagon wheels and thereby slowing down the wagon. As you can imagine such exposed brakes are associated with considerable maintenance work required to remove leaking oil and weather-related problems such as freezing. Then FEW Blankenburg had a great idea.
Electromagnetic rail brakes – Electric power instead of hydraulics and pneumatics
Instead of interference and wear prone hydraulic and pneumatic systems, the braking system operates with electric power; the movement of the brake carriers in the track bed is initiated magnetically. The brake carriers, equipped with magnetic technology, are integrated into both sides of the railway line. They are mobile and press, during braking, against the wheel. Braking current and magnetic field depend on the data, which is calculated for the braking process and can reach 600A with 750V DC voltage.
The highlight – The electricity comes from high-power capacitors
So that the required braking power is available at any time, without extreme high peak load in the electricity network, it is taken from high-performance energy storage. These capacitors are charged continuously. The rolling process is only triggered when sufficient energy has been stored for the braking operation in the capacitors. The storage dimensions are so chosen that even a UPS can be dispensed with.
A controller for everything – with powerful VIPA technology.
The demands on the automation technology were very high. All sequencing and control processes from charging the energy storage to the precisely calculated braking current should run via a CPU as well as the fast and secure processing of all values measured. Status messages in the control center can amount to more than 700 variables. Not only the clock speed, which was feasible, speaks for VIPA CPUs, but also the communication via the MPI interface, which, together with the VIPA specialists, had to be adapted for this application. Also the visualization was accessed on 10" Touch Panels from VIPA, the ease of use in conjunction with the Movicon interface was impressive.
This technology was first installed in the Seddin marshalling yard near Berlin back in 2006, and has been running flawlessly since then.