By Abner MolinaUTA REU Summer 2013

Group: Dr. Chiao

Midterm Presentation

Date: 7/9/2013

WIRELESS POWER TRANSMISSION

OVERVIEW

• Experimental Objective

• Introduction

• Background Information

• Materials

• Procedure

• Data/Observations

• Results

• Conclusion

EXPERIMENTAL OBJECTIVE • Increase efficiency of wireless power being transmitted through:

• Different design of antennas (repeaters)

• Different circuitry:

• Class E amplifier

• Phase lock loop (PLL)

INTRODUCTION • Done by Peter Woods

BACKGROUND INFORMATION

• University of Hong Kong conducted study in Mid-Range Wireless Power Transfer

• With:

• 2-coil systems

• 4-coil systems

• Coils used in study were all radial[1]

• Goal is coming up with a better design

BACKGROUND INFORMATION

• Designs: • Repeater 1:

Inductance 93.36 μH

Outer Radius 18 cm

Inner Radius 5 cm

Spacing 0.5 cm

BACKGROUND INFORMATION • Repeater 2:

Inductance 40.74 μH

Outer Radius 18 cm

Inner Radius 14 cm

Spacing 0.5 cm

BACKGROUND INFORMATION• Repeater 3:

Inductance 28.72 μH

Outer Radius 18 cm

Inner Radius 5 cm

Spacing 1 cm

BACKGROUND INFORMATION • Repeater 4, Reciever, Transmitter:

Inductance 176.3 μH

Outer Radius 18 cmTurns 10

BACKGROUND INFORMATION

• Class E Amplifier• RF choke allows

• DC current to flow when switch on

• Blocks AC signals when switch off

• Shunt capacitor charges and discharges in on-off cycle

• Tuning allows fundamental sinusoid to appear at ouput [2]

• Tuning allows circuit to be at resonating frequency

• Max power

BACKGROUND INFORMATION

• Class E Amplifier [2]

MATERIALS

• Litz Wire

• Antenna Frame

• Capacitors

• Oscilloscope

• Function Generator

• DC Power Supply

PROCEDURE

• Set Up

DATA/OBSERVATIONS (40 CM)

0 5 10 15 20 25 30 35 4002468

1012141618

Repeater 1

Distance (cm)

Effic

ienc

y (%

)

0 5 10 15 20 25 30 35 4002468

1012141618

Repeater 2

Distance (cm)

Effic

ienc

y (%

)

0 5 10 15 20 25 30 35 4002468

1012141618

Repeater 3

Distance

Effic

ienc

y (%

)

DATA/OBSERVATIONS (60 CM)

0 10 20 30 40 50 60 700

5

10

15

20

25

30

Repeater 1

Distance (cm)

Effic

ienc

y (%

)

0 10 20 30 40 50 60 700

5

10

15

20

25

30

Repeater 2

Distance (cm)

Effic

iecn

y (%

)

0 10 20 30 40 50 60-5.00%

0.00%

5.00%

10.00%

15.00%

20.00%

25.00%

30.00%

Repeater 3

Distance (cm)

Effc

iecn

y (%

)

DATA/OBSERVATIONS (80 CM)

0 10 20 30 40 50 60 70 80 900123456789

10

Repeater 1

Distance (cm)

Effic

iecy

(%)

0 10 20 30 40 50 60 70 80 900123456789

10

Repeater 2

Distance (cm)

Effic

ienc

y (%

)

0 10 20 30 40 50 60 70 80 900.00%1.00%2.00%3.00%4.00%5.00%6.00%7.00%8.00%9.00%

10.00%

Repeater 3

Distance (cm)

Effic

ienc

y (%

)

0 10 20 30 40 50 60 70 80 900123456789

10

Repeater 4

Distance (cm)

Effic

ienc

y (%

)

RESULTS

• 40 CM

• Repeater 1 produce higher efficiency

• 60 CM

• Repeater 1 produce higher efficiency

• 80 cm

• Repeater 3 produce higher efficiency

CONCLUSION

• Repeater 1 produced higher efficiency for:

• 40 cm

• 60 cm

• Repeater 3 produced higher efficiency for 80 cm

• Test designs using PLL

• Using new Litz wire

• Produce more control experiments

• Incorporate LABView for precise results

ACKNOWLEDGMENTS• [1] Lee, C.K.; Zhong, W.X.; Hui, S.Y.R., "Recent progress in mid-range wireless power

transfer," Energy Conversion Congress and Exposition (ECCE), 2012 IEEE , vol., no., pp.3819,3824, 15-20 Sept. 2012doi: 10.1109/ECCE.2012.6342288

• [2] Tao Wang. “Optimized Class-E RF Power Amplifier Design in Bulk CMOS.” ProQues, 2007. Web.

ANY QUESTION?