Braking, Electric

deceleration or complete cessation of the translational or rotary motion of machines, vehicles, or moving parts, achieved by converting the machine’s kinetic or potential energy into electric energy or by switching the windings of the actuating electric motor in such a way that the direction of the tractive force is reversed. In electric braking, the electric motor’s direction of rotation remains the same as during normal operation, but the electric torque acting on the armature or rotor has an opposite direction. There are several distinct types of electric braking: rheostatic, regenerative, reverse-current, and combined, such as regenerative-rheostatic, braking.

Electric braking is used in transportation in electric locomotives, streetcars, and trolleybuses; it also finds application in hoisting and conveying machines that use traction motors. The use of electric braking reduces brake-shoe wear in mechanical brakes; under certain circumstances, for example, when used on railroad main lines in mountainous sections, it yields a substantial saving of electric power.