Transcript Low AC and DC Resistance Inductor Technology

Low AC and DC Resistance
Inductor Technology
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Weyman Lundquist – President and CEO
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West Coast Magnetics
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April 4, 2007
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International Patent # WO 2005/09630
Patented Inductor Technology
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Very Low DCR, High Window Utilization
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Foil winding
AND Low AC Resistance
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AC loss reduction comparable to litz wire
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SIGNIFICANTLY LOWER TOTAL LOSSES
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Applies to:
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Gapped core structures
Idc > 10 amps
Ripple > 5%
Inductors (Chokes)
West Coast Magnetics is:
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A Manufacturing Driven Organization
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A Customer Driven Organization
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Lean since 2005
100% on-time delivery
100% defect free product
Service
Engineering Support
A Technology Innovator
West Coast Magnetics
Company History
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Founded in 1976 in Silicon Valley
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Present Ownership 1993
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Open Stockton facility in 1996
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Acquired Mexico Facility in 1999
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New Inductor Technology 2003
Company Overview
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Stockton, CA
• Corporate Headquarters and Manufacturing Facility
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Tecate, MX
• Production Facility
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Custom and Standard Products
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Power Transformers: 50/60 Hz to 13.56 MHz
Power Transformers: 1 Watt to 15 kW
Power Inductors to 200 amps
Common Mode Chokes to 200 amps
Current Sense Transformers 60 Hz to 13.56 MHz
RF Inductors to 100 MHz
How Does it Work?
By cutting away a section of the foil
winding in the region of the core gap
winding eddy currents are concentrated
locally in the region of the cutaway.
Experiment: Is the New
Technology Really Better?
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Objective: A Conclusive Comparison of
the New Technology to Conventional
Windings
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Step 1: Define the Inductor
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Inductance 90 uH
Current 40 Adc
Ripple: Triangle wave at 50 kHz
Core: E70/33/32 Epcos N67 material
Gap: 2.64 mm (1.32 mm each center leg)
Turns: 15
Experiment: Is the New
Technology Really Better?
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Step 2: Wind Inductors with Conventional
Windings Using Best Practices
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Full window
Single layer
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Step 3: Determine Winding Losses for
each Inductor as a Function of Ripple
Magnitude
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Step 4: Compare Results to Temperature
Rise Data Collected under Load.
Winding Cross Sections
Long Cut
Full Foil
20/32 Litz
20/32 Litz
Prototype Cut
400/40 Litz
Solid Wire
Solid Wire
50/40 Litz
Method of Estimating
Losses
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DCR – Measure voltage drop under 5 Amp
DC load.
Core Losses: Derived from Epcos loss
curves.
AC resistance – Sweep from 10 kHz to
200 kHz with Agilent 4294A network
analyzer
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Use Fourier decomposition to translate
sinusoidal sweep data to triangular waveform
Total Loss Comparison
Temperature Rise
Measurement – Test Set Up
90 uH
20 uF
10 Ohms
2.5 Ohms
40 A
Device
Under
Test
Amplifier
Output: 6A P-P
Function
Generator
Temperature Rise Measurement –
Results at 15% Ripple
Global Market – High
Growth Green Energy!
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Distributed Power: Wind, Solar and FACTs
 Estimated $4.3 Billion in Power Electronic Equipment in 2007
 15% plus forecasted growth
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Hybrid Vehicles
 Est. 600,000 in 2007
 50% plus forecasted growth
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Uninterruptible Power Supplies
 Estimated $4 Billion in Power Electronic Equipment > 1 kW in
2007
 7% plus forecasted growth
Design Tools
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Code for Winding Loss Simulation
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Code for Translation of Winding
Cross Section into 2D Foil Shape
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Code for Prediction of H vs. L vs.
Gap for any Inductor
Licensing Opportunity
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Objective: The widest possible
application of the technology.
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Develop tools for design support.
Maintain license rate at a level which will lead
to widespread use.
Contact: Weyman Lundquist
[email protected]
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800-628-1123
Thank you for your time
Weyman Lundquist, President
West Coast Magnetics
4848 Frontier Way, Ste 100
Stockton, CA 95215
www.wcmagnetics.com
800-628-1123