Ads Here

Saturday, August 3, 2019

Meant By Regenerative Braking in Motors

What Is Meant By Regenerative Braking in Motors?

When the supply is cutt off for a running motor, it still continue running due to inertia. In order to stop it quickly we place a load(resitor) across the armature winding and the motor should have maintained continuous field supply. so that back e.m.f voltage is made to apply across the resistor and due to load the motor stops quickly.This type of breaking is called as “Regenerative Breaking”

Regenerative braking utilizes motor’s kinetic energy in to useful purpose such as recharging battery or returning electrical energy back to mains where it is utilized by other electric locomotives operating on the same overhead lines.

In regenerative breaking DC motor act as a generator. It convert kinetic energy in to electrical energy and return it to the mains for fully controlled SCR bridge rectifier or return to (charge) battery in case of battery operated vehicles.
With fully controlled SCR bridge rectifier of positive and negative converters, DC motor can have four quadrant operation i.e. forward/reverse driving and respective regenerative breaking as shown in the above figure.

The only disadvantage of this type of braking is that the motor has to run at super synchronous speed which may damage the motor mechanically and electrically, but regenerative braking can be done at sub synchronous speed if the variable frequency source is available.

No comments:

Post a Comment