Automatic drive and brake control
The Automatic traction and brake control (abbreviation: AFB ) is a technical system, in the traction vehicles , is the railway used by the driver to assist in his work. The system takes on the task of accelerating or decelerating the vehicle and the train to a speed (V soll ) preselected by the driver and maintaining this speed. In the English-speaking world, such systems are referred to as Automatic Train Operation .
For this purpose, the driver specifies a speed by means of a V soll adjuster; the AFB then automatically sets the necessary tractive and braking forces; To do this, it uses the engine brake as well as the continuous train brake. The amount of traction can be influenced via the traction control, while braking always takes place with fixed deceleration values. The driver always retains control of the vehicle and can intervene at any time by switching off the tractive power or manually braking with the driver's brake valve. The AFB is temporarily deactivated, just as it can be completely switched off at any time.
As a second variant, the Rhaetian Railway (RhB) has controls in which the driver can only specify V should and has no direct influence on the force, as in this variant the force is determined and specified fully automatically by the controller.
The AFB can mainly be found in modern vehicles, such as the Intercity Express , locomotives of the 101 series and others. Some subway systems also use AFB. AFB is a basic requirement for driverless rail systems.
The 103 series machines presented in the mid-1960s were the first locomotives in Germany to be equipped with automatic speed control.
In conjunction with effective line train control (LZB), the AFB can - with appropriately equipped on-board equipment - automatically regulate the speed of a train taking into account the LZB reference variables so that it never exceeds the permissible speed V max . The system can automatically accelerate again after braking, but it does not recognize any scheduled stops if these are not signaled.
As with manual control, the driver always retains full responsibility for the safe execution of the train journey. Since the automatic driving with AFB and LZB on many routes with fully configured traction and V soll actuator (then V soll = V max ) leads to a very dynamic driving behavior of the train (unnecessarily strong accelerations and decelerations, no anticipatory driving), Train drivers switch traction and V should only be completely free when it makes sense. As a result, energy savings in particular can be achieved in addition to greater driving comfort.
Individual evidence
- ↑ Michael Nold: Speed controller for trains with longitudinal oscillations . In: Swiss Railway Review . No. December 12 , 2018.
- ↑ Deutsche Bundesbahn (Ed.): Even faster ... The high-speed trip on the Deutsche Bundesbahn . Six-page brochure, ca.1965.