Alternators 101

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Alternators 101

• Aaron Ferber
• Laboratory for Intelligent Mechanical Systems
• Northwestern University

Be sure to read the Notes section of this
presentation
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Alternators 101

• Three Main components
• Rotor
• Stator
• Diode Pack

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Alternators 101
Diode Pack
Vout
Stator Coils
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Rotor
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Alternators 101
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Alternators 101
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Alternators 101
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Alternators 101
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Alternators 101
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Alternators 101
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Alternators 101
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Alternators 101
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Claw Pole Design
Two Poles
V
t
Twelve Poles
V
t
Image taken from http//www.ansoft.com/news/articl
es/Kudla_2.pdf
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Connections
DC Output
AC Tap / Tachometer
Ground
Indicator Light
Field (Rotor) Terminals
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Use in Vehicles
Alternator
Engine
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Use in Vehicles
Alternator
Engine
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Use in Vehicles
Alternator
Engine
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Generators vs. Alternators
Generator
Alternator
Convert rotational motion into DC electrical
output
Magnet spun inside wires Diode
rectifier Outputs even at idle speeds Handles
higher currents No polarizing requirement
Wires spun inside magnets Commutator High speed
requirement Low current restriction Must be
polarized
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Electrical Damping
Diode Pack
Stator Coils
-
Rotor
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Electrical Damping
?
y
m
a
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Efficiency