Regenerative braking refers to the braking process in which the kinetic energy of the vehicle is recovered during the braking operating and supplied back to the mains or stored in a battery. Regenerative braking thus improves efficiency by recovering the energy which would be lost in a braking action.
In conventional forms of braking, the kinetic energy of a moving vehicle is converted into heat by the braking pads or the linings. Regenerative braking is usually done in vehicles where the final drive is electric. Electric trains and Trams and electric cars are examples where regenerative braking can be readily applied. In regenerative braking, the motor which drives the wheels can be made to work as a generator which feeds power to the mains.
This done by disconnecting the power supply to the motor driving the wheels and reconnecting it either to the power through diodes or to capacitors. The kinetic energy in the wheels, rotates the motor which works as a generator. The power at the terminals of the generator is connected to the power supply or alternatively to a capacitor.
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