Transcript Eddy Currents and Eddy Current Losses • Solid Iron Core ECE 441

Eddy Currents and Eddy Current Losses
• Solid Iron Core
• Laminated Core
ECE 441
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Eddy currents in a solid core
• Eddy currents
circulate within
concentric shells, or
loops
• Voltages generated
proportional to flux
e 
e
d
dt
E  f B
e
ECE 441
max
2
Eddy currents in a laminated core
• Smaller paths reduce
the eddy currents and
voltages
• Eddy current loss is
expressed as power
P  eddy  current  loss (W / unitmass )
e
f  frequency  of  flux  wave(Hz )
B
max
Pe  ke f B
2
2
max
 max  value  of  flux  wave(T )
k  cons t an t
e
ECE 441
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