eddy current brakes
TRANSCRIPT
EDDY CURRENT BRAKES
PRESENTED BY:M.PRIYA VANDANA P.V.SAI PRIYA
CONTENTS: Introduction of Eddy Current. Introduction of Eddy Current
Brake.Working Principle. Types of Eddy Current Brakes. Advantages and Disadvantages. Applications. Conclusion.
WHAT IS A BRAKE?
EDDY CURRENT:
An Eddy Current is a Swirling current set up in a Conductor in response to a Change in Magnetic Field.
EDDY CURRENT : CONDUCTOR FLUCTUATING MAGNETIC FIELD
VOLTAGE
CURRENT
EDDY CURRENT
EDDY CURRENT BRAKES: It is a device used to slow a moving
object by creating eddy currents.
Braking action is made by Varying the Strength of the Magnetic Field.
A Braking Force is possible when an electric current is passed through the Electromagnets.
EDDY CURRENT BRAKES:
WORKING PRINCIPLE:
Eddy Current brake is based on Two basic Principles of Electromagnetics,which are
Faraday’s Law
Lenz Law
FARADAY’S LAW: It states that change in magnetic flux
induces an EMF in the circuit.
LENZ LAW:“ An induced EMF always gives rise to
a current whose magnetic field opposes the original change in magnetic flux”
WORKING: Electromagnets produce Primary
magnetic field from supplied current which in turn produces eddy current.
Eddy Current produces secondary magnetic field which opposes the primary field.
Opposing magnetic field reduces the Velocity
WORKING:
Circular Eddy current Brakes.
Linear Eddy Current Brakes.
TYPES OF EDDY CURRENTS
CIRCULAR EDDY CURRENT BRAKES: Brake assembly is Circular in Shape.
Consists of disc(magnetic material) placed between the poles.
Conductor coils are wound on the poles and when the disc rotates through the magnetic field creates Eddy Currents.
CIRCULAR EDDY CURRENT BRAKES:
LINEAR EDDY CURRENT BRAKES: The Linear Eddy Current Brake
Consists of a magnetic yoke with Electric coils placed along the rail.
This magnet is kept at a distance of 7m from the rail.
When the magnet is along the rail it generates the eddy
currents.
LINEAR EDDY CURRENT BRAKES:
LINEAR EDDY CURRENT BRAKES:
ADVANTAGES: No wear or Tear. No Noise or Smell. Adjustable Brake Force. Uses Electromagnetic force instead of
Friction. Low maintenance. Light weight.
DISADVANTAGES:
Breaking Force diminishes as Speed diminishes.
Very Tough Design and Simulation. No ability to hold load in Standstill
position. Acts like a Governor to reduce the
Speed. We cannot Use it for Low speed
Vehicles.
APPLICATIONS: In high speed trains. In roller coaster for braking and smooth
functioning. It is also used in vehicles but still not widely
used.
CONCLUSION:We can make Use of Opposing tendency of eddy current to control the speed of High Speed Vehicles without any Wear and Tear.