11/25/2015
Announcements
• SAIS open now – please fill it out
− Remaining students:
 15 9 in 481
 2 0 in 599
• Final Exam:
− Posted online after final class
− Due before end of scheduled exam time
 Monday, Dec 9th, 10:00 am
13.3 Magnetics Losses
Magnetic Device Losses
Copper Loss
DC Copper Loss
Core Loss
AC Copper Loss
Eddy Current
Residual
Hysteresis
Skin Effect
Proximity Effect
Fringing
Flux
High Frequency Losses
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The Kg Method
Kg Method
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Discussion
Alternate Applications
• Can be applied to multiple‐winding magnetics as long as design goals apply
− Core loss negligible
− Saturation is limiting peak flux density
• 14.3 shows how the method changes
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Allocation of Window Area
Chapter 15: Transformer Design
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Transformer Design Constraints
Power Loss Tradeoffs
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Minimizing Total Loss
Calculation of Total Loss
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The Kgfe Method
The Kgfe Method
nk  n1
Awk 
nk
n1
 2 K uWA
n2
Verify Bmax < Bsat
7