Regenerative Braking System (RBS)
Group Members:
Olufemi Odutola, Isaac Donkor, Getachew Tesfamariam, Theodore Kahiya
Abstract:
In recent years, increased concerns over the impact of the conventional car (ICE – Internal Combustion
Engine) on the environment have led to renewed interest and advancement in the Electric Vehicle (EV).
While the advancements in the EV technology have been able to overcome many of its initial limitations,
the need to improve overall efficiency of the vehicle has led to the design of the regenerative braking
system (RBS). The RBS will be used to convert the car’s mechanical energy and also the heat that would
have been lost during braking into electrical energy. The 3 most important aspects of the design have
been listed below.
Braking
The RBS would be controlled using a PWM signal generated from a microcontroller. The duty cycle of
the PWM signal would in turn depend on the response to a variable resistor which will be used to model
the conventional braking. A higher resistance would generate a PWM signal with a higher duty cycle and
in turn, a higher braking intensity. Therefore by varying the resistor value, the braking intensity can also
be varied. The motor to be used in this system will primarily be a DC Motor. We intend to switch to an
induction motor later on as this is currently the norm in the BEV (Battery Electric Vehicle) industry.
Energy Storage
In other to maximize the efficiency of the RBS, it is important that we store some of the energy that may
have otherwise been wasted. To achieve this, we implement the use of large capacitors connected in
parallel to store the energy. This energy could then be used to recharge the batteries of the Electric
vehicle (EV)
Visuals
Typically in the conventional car, we can monitor the amount of fuel as well as speed of the vehicle.
Similarly in our electric vehicle, we would like to physically see the amount of charge stored and sent to
the batteries. Also we would like to monitor the speed of the motor and this significantly contributes to
the RBS. For simulation purposes, it is also important to display the braking intensity applied. These
visuals will be achieved through a Visual Basic programming interface.
References:
1. Ultra Capacitors + DC-DC Converters in Regenerative Braking System
http://journals1.scholarsportal.info/tmp/12943276643356749396.pdf
2. Regenerative Braking for a Hybrid Electric Vehicle
http://www.google.ca/patents?hl=en&lr=&vid=USPATAPP10063143&id=HNOIAAAAEBAJ&oi=fn
d&dq=regenerative+braking&printsec=abstract#v=onepage&q&f=false
3. Regenerative braking http://en.wikipedia.org/wiki/Regenerative_brake
4. What is Regenerative Braking? http://www.wisegeek.com/what-is-regenerative-braking.htm
5. Regenerative braking system
http://www.google.ca/patents?hl=en&lr=&vid=USPAT2027865&id=NJhBAAAAEBAJ&oi=fnd&dq
=regenerative+braking+system&printsec=abstract#v=onepage&q&f=false