Low AC and DC Resistance Inductor Technology Weyman Lundquist – President and CEO West Coast...

Low AC and DC Resistance Inductor Technology

Weyman Lundquist – President and CEO

West Coast Magnetics

April 4, 2007

International Patent # WO 2005/09630

Patented Inductor Technology

Very Low DCR, High Window Utilization Foil winding

AND Low AC Resistance AC loss reduction comparable to litz wire

SIGNIFICANTLY LOWER TOTAL LOSSES

Applies to: Gapped core structures Idc > 10 amps Ripple > 5% Inductors (Chokes)

West Coast Magnetics is:

A Manufacturing Driven Organization Lean since 2005 100% on-time delivery 100% defect free product

A Customer Driven Organization Service Engineering Support

A Technology Innovator

West Coast MagneticsCompany History Founded in 1976 in Silicon Valley

Present Ownership 1993

Open Stockton facility in 1996

Acquired Mexico Facility in 1999

New Inductor Technology 2003

Company Overview Stockton, CA

• Corporate Headquarters and Manufacturing Facility

Tecate, MX • Production Facility

Custom and Standard Products• 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?

Objective: A Conclusive Comparison of the New Technology to Conventional Windings

Step 1: Define the Inductor 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?

Step 2: Wind Inductors with Conventional Windings Using Best Practices Full window Single layer

Step 3: Determine Winding Losses for each Inductor as a Function of Ripple Magnitude

Step 4: Compare Results to Temperature Rise Data Collected under Load.

Winding Cross Sections

20/32 Litz Solid Wire400/40 Litz

Full Foil Long Cut

50/40 Litz

Prototype Cut

Solid Wire20/32 Litz

Method of Estimating Losses 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 Use Fourier decomposition to translate

sinusoidal sweep data to triangular waveform

Total Loss Comparison

Temperature Rise Measurement – Test Set Up

40 A

20 uF10 Ohms

2.5 Ohms

AmplifierOutput: 6A P-P

Function Generator

Device Under Test

90 uH

Temperature Rise Measurement – Results at 15% Ripple

Global Market – High Growth Green Energy! Distributed Power: Wind, Solar and FACTs

Estimated $4.3 Billion in Power Electronic Equipment in 2007 15% plus forecasted growth

Hybrid Vehicles Est. 600,000 in 2007 50% plus forecasted growth

Uninterruptible Power Supplies Estimated $4 Billion in Power Electronic Equipment > 1 kW in

2007 7% plus forecasted growth

Design Tools Code for Winding Loss Simulation

Code for Translation of Winding Cross Section into 2D Foil Shape

Code for Prediction of H vs. L vs. Gap for any Inductor

Licensing Opportunity

Objective: The widest possible application of the technology. Develop tools for design support. Maintain license rate at a level which will lead

to widespread use.

Contact: Weyman Lundquist wlundquist@wcmagnetics.com 800-628-1123

Thank you for your time

Weyman Lundquist, PresidentWest Coast Magnetics4848 Frontier Way, Ste 100Stockton, CA 95215

www.wcmagnetics.com800-628-1123