'''Regenerative braking''' is any technology which allows a
vehicle to recapture and store part of the
kinetic energy that would otherwise be
lost to
heat when
braking. A simpler technology that only converts the energy to
heat but which uses similar principles is known as
dynamic braking. Both are most commonly seen on electric or
hybrid vehicles. Braking is accomplished by electrically switching motors to act as generators that convert
motion into electricity instead of electricity into motion. Traditional friction-based brakes must also be provided to be used when rapid, powerful braking is required. Estimates currently see 30% efficiency; however, the actual efficiency depends on numerous factors, such as the state of charge of the battery, how many wheels are equipped to use the regenerative braking system, and whether the topology used is parallel or series in nature.
Electric railway vehicles feed the recaptured energy back into the
grid, while road vehicles store it for re-acceleration using
flywheels,
batteries or
capacitors. Older dynamic brake systems generally used the electricity to provide heat or just passed it through large banks of
resistors to dissipate the energy.
Hydraulic System
This is a patented system currently in development by Permo-Drive, a small
Australian company. It is designed to replace the current
engine braking system on trucks and boasts better efficiency, less noise as well as other benefits over engine braking.
The mechanism is attached to the
driveshaft of the vehicle and when brakes are applied feeds energy into
accumulators and is stored as
hydraulic fluid under great
pressure. The energy is then released again into the drive shaft when the vehicle is accelerating. This system is claimed to withhold up to 40% of the energy otherwise wasted in braking.
Category:Automotive braking technologies
Category:Locomotive parts
ja:回生ブレーキ
zh:再生制動