MQP DCP 1-2012: Magnetic Braking
Michael Scanlon Advisor: David Planchard
Co-Advisor: Alexander Emanuel
Eddy Current Brake This design is intended to be used as an
electric motor - eddy current brake system
The significance of this system is automotive applications
Background Research
Began with a concept Rollercoasters use eddy current brakes to slow
the car
Idea blossomed to encompass vehicles
Background Electrical and Computer Engineering
Research Professor Alexander Emanuel was
recruited to explain and help conceptualize properties
Lorentz Forces
Self-taught ECE Had not taken an Electrical and Computer
Engineering course at WPI
Why?… Efficiency System is designed to be used in automotive
applications
“No Wear” brake This is not a friction brake No material wear
Highly Efficient
Already used on trains
Why?… Safety System can be managed by available hardware
and software (ABS, Traction Control, and Stability Control systems)
Simplifies the management systems – entire vehicle can be controlled by a laptop size computer
Real time system corrections – speed of electricity
Why?… Application Large truck applications (18 wheel trucks)
We could design a truck to have independent wheel electric motor – eddy current brake setups on all axles
Design truck’s trailer to have motor – brake on axle
Large vehicle can contain large batteries Vehicle travels at speed most of the time –
this means that the motors will not have to work hard Regenerative technology Turning off motors while at speed to generate power and recharge batteries
Quiet Trucks!
Design Prototype #1
Cons Costly to build Unsafe to test Variables
unaccounted for
Prototype #2 Cons
No real world variables
Difficult to simulate a flywheel/ motion of a vehicle
Construction Machining
All machining was done by myself – although I did have assistance from the Washburn Shops faculty and everyday students (Grads and Undergrads)
Turning Steel Copper
3 – Axis Milling
Wood Steel Copper
Construction Coiling
Each of the 4 coils had to be coiled by hand
Each layer of coils had to layered with epoxy
Coiled 180x each Wood core mold needed to
be constructed
How it works Automotive Application 1. Motor spins to full RPM – car accelerates 2. Motor is shut off – as brake pedal is
applied 3. Eddy current brake is powered up to a
calculated current – determined by brake pedal
4. As brake become ineffective motor is powered in reverse – bringing the vehicle to a stop
5. Additional mechanical brake is applied as a Parking Brake
How it works Testing Procedure
The experiment will run as follows: 1. The motor will be spun up to full RPM
(around 3400 RPM) 2. The attached DC motor will begin
recording the voltage output and a baseline reading will be determined
3. The motor will then be shut off (as to not interfere with the eddy current brake)
4. The eddy current brake will then be powered at a pre-determined interval (the power intervals are in units of Amps)
5. The output voltage from the DC motor will then be recorded with respect to time (obtaining deceleration)
6. This test will be repeated for multiple power intervals
The experiment should produce a velocity graph similar to this one. The force is directly proportional to the velocity and as such the velocity will decrease but never reach zero.
Expected Outcomes:
Conclusion This system can make a difference in the
simplicity and efficiency of modern vehicles
Electricity is the most abundant and renewable resource available
These properties have been proven in real world application for years
Major Setbacks: Power storage available High amperage batteries with large
capacity Changing everybody's minds about electric
vehicles
References Images not taken by myself are Google images Special Thanks to:
Professor Alexander Emanuel Torbjorn Bergstrom Neil Whitehouse Adam Sears Corey Stevens James Loiselle Mike Flaherty Other Undergraduate work study students that I relentlessly used as
sounding boards Thank You All for Your Help!