23-04-2011, 11:21 AM
PRESENTED BY
ABHISHEK KUMAR
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LINEAR MOTORS AND IT’S USE IN MAGLEV TRAIN
INTRODUCTION
A LINEAR MOTOR OR LINEAR INDUCTION MOTOR IS AN AC ELECTRIC MOTOR THAT HAS ITS STATOR UNROLLED SO THAT INSTEAD OF PRODUCING A TORQUE(ROTATION) IT PRODUCES A LINEAR FORCE ALONG ITS LENGTH.
HOW LINEAR MOTORS WORK
SPLIT A ROTORY MOTOR RADIALLY ALONG ITS AXIS OF ROTATION
FLATTEN IT OUT:
RESULT: A FLAT LINEAR MOTOR THAT PRODUCES A DIRECT LINEAR FORCE INSTEAD OF TORQUE.
ANALYSIS METHOD
ANALYSIS IS SIMILAR TO THAT OF ROTARY MOTORS
LINEAR DIMENSION AND DISPLACEMENT REPLACES THE ANGULAR ONES.
FORCE REPLACES THE TORQUE
TWO MOTOR COMPONENTS
MOTOR COILFORCER)
ENCAPSULATES COPPER WINDING WITHIN A CORE MATERIAL.
COPPER WINDING CONDUCT CURRENT
MAGNETIC RAILROTOR)
SINGLE ROW OF MAGNET OR DOUBLESIDED.
RARE EARTH MAGNET MOUNTED IN ALTERNATING POLARITY ON A STEEL PLATE TO PRODUCE MAGNETIC FLUX DENSITY.
GENERATING FORCE
FORCE(F) IS GENERATED WHEN THE CURRENT AND FLUX DENSITY(B) INTERACT
F=I x B
Applications of LIM
Small Linear Motors
Packaging and Material Handling
Automated Assembly
Reciprocating compressors and alternators
Large Linear Induction Machines (3 phase)
Transportation
Materials handling
“Most widely known use of linear motors is in the transportation field .
Maglev Trains
Principle of:
levitation
Propulsion
Lateral guidance
Propulsion
Guideway, Guideway point
LIM Drive principle
Energy supply
Control of operation
advantages
Principle of Magnetic Levitation
Principle of Lateral Guidance
Principle of Propulsion
Guideway
Guideway points
The vehicle changes tracks by way of flexible steel-beam points installations. Each one consists of a continuous steel beam which is bent within its elastic limits to form the turnout with the aid of an electromechanical actuating drive motor. The length of the beam varies from 78 to 150m depending on the design speed at the location. The guideway can be adapted to suit the landscape and placed alongside existing traffic routes.
LIM Drive principle (propulsion)
Energy supply to the section a guideway (Propulsion)
Control of operations
Advantages of maglev train
It is faster
Safer
More environmental friendly
Ease congestion of major city centres, highways and freeways and also the airways
Linear Motor Advantages
Zero Backlash
low-inertia drive
High Speeds
High Accelerations
Fast Response
High repeatability
Highly accurate
Clean Room compatibility
Linear Motor Disadvantage
COST!
In most cases, the upfront cost of purchasing a linear motor system will be more expensive than belt- or screw-driven systems