EDDY CURRENT RETARDER

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EDDY CURRENT RETARDER
Indian Institute of Technology
Hyderabad
DIPIN K NAIR ME12B1014 KENNETH JOSEPH
PAUL ME12B1020 NAVANEETH T CHANDRAN ME12B1025 V
IVEK D S ME12B1044 VIVEK A K ME11B1037
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INTRODUCTION

• This projects intends to the design and
  implementation of new system of retardation
  (braking) for automobiles
• The design of the new brakes is based upon the
  phenomenon of electromagnetic induction and eddy
  currents
• The design basically consists of very strong
  magnet and rotating metallic wheel
• The wheel develops eddy currents due to the
  change in magnetic flux associated to the wheel
  due to its rotation
• The eddy current development obeys Maxwells law
  of electromagnetic induction and Lenzs law of
  direction of induced current
• The current in turn dissipates the rotational
  energy of the wheel as heat bringing the wheel to
  a stop

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EXISTING BRAKING METHODS

• Drum brakes
• Disk brakes
• Hydraulic brakes
• Electric brake
• ABS (Anti skid Braking System)

Disk brake
Air brake
Disk brake
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NEED FOR ALTERNATIVE

• All conventional systems of braking in road
  vehicles uses development of contact friction for
  retardation
• These systems are probe to the wear and tear on
  usage
• Conventional braking systems produces continuous
  power dissipation as heat and may fail if the
  temperature rises too high
• Friction based braking methods are also not
  efficient under wet conditions
• Weight brakes add additional weight to the
  automobile serving no other purpose and
  significantly reducing traction under certain
  circumstances
• Brakes usually creates small noise on application
  and may also create loud screeches on hard usage

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DESIGN

• The design consists of following parts
• Aluminium wheel
• Mild steel shaft
• Free wheels
• Strong permanent magnet
• 12v DC motor
• 12v /2.5 Ah lead battery
• Metallic frame
• Braking arm

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PROS

• High impact
• Less friction
• Low maintenance requirement
• Less noise
• Simple in design
• High degree of safety

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CONS

• Failure to act as a holding device
• Usage of electric power for braking
• Less effective under very low velocities

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APPLICATIONS

• Already in use under some railway system
• Can be used for any road vehicles
• Equally applicable to heavy and light vehicles
• Can be used as additional retarder for aircrafts
• May also find application in virtually any
  rotating system which have metallic parts