1. 2014
Capstone Design RF wireless power transmission 6.78Mhz Bandwidth magnetic resonance method efficiency of power transfer
김용빈
안중혁
담당교수 : 전석희
월 5~6교시 , 화 1교시

2. Data comparison and Practice
Time table
Contents 1w 2w 3w 4w 5주 6w 7w
8w MID 9w
10w
11w
12w
13w
14w
15w
Data research
Theory 
&
Measurement
Schematic
Circuit Design
Tool
practice
experiment
Feed back
And
compare
Data comparison and Practice
Final cleanup

3. Sketch initiative

4. Magnetic resonance method
Problem Proposal 1
Magnetic resonance method
1 : N
LED Position 2
Number of
repeating coil
Load power transfer

5. Coil conditions
Litz Wire

6. Previous Study case : The same distance Resonant frequency : 1.7MHz
Transmission distance and efficiency
case : The same distance
Gain and repeating coils

7. 4coils , D: 600㎜

8. 5colis, D : 600㎜

9. 6colis, D : 600㎜

10. Result Condition1 : The same coils k(Coupling coefficient)↑(k≤1) dB↑
Condition 2 : The same k
Number of repeating coil ↑
But, In simulation 5-6coils, Number of repeating coil ↑
because distance ↑, dB↓

11. Background
6.78 MHz

12. Study Content D : 600 ㎜ N (Turns) 10 9 8 7 6 5 4 3 2 L (μH) C (㎊) ƒ(㎒)
118.90
97.22
77.55
59.95
44.47
31.20
20.16
11.45
5.14
C (㎊)
80.16
84.18
88.95
94.70
101.85
111.06
123.55
141.86
172.60
ƒ(㎒)
1.630
1.759
1.916
2.112
2.364
2.703
3.188
3.949
5.343
D : 650 ㎜
N (Turns) 10 9 8 7 6 5 4 3 2
L (μH)
129.74
106.02
84.51
65.29
48.40
33.92
21.90
12.44
5.58
C (㎊)
90.13
94.67
100.05
1.655
114.61
125.00
139.08
159.73
194.40
ƒ(㎒)
1.471
1.588
1.730
1.908
2.136
2.444
2.883
3.570
4.832
D : 300 ㎜
N (Turns) 10 9 8 7 6 5 4 3 2
L (μH)
54.34
44.78
36.01
28.07
21.00
14.86
9.69
5.56
2.52
C (㎊)
29.26
30.66
32.32
34.33
36.84
40.08
44.47
50.93
61.77
ƒ(㎒)
3.991
4.295
4.665
5.126
5.722
6.521
7.666
9.457
12.756

13. D : 600㎜ 4coils
Dissatisfaction

14. D : 650㎜ 4coils
Dissatisfaction

15. D : 300㎜ 4coils
satifaction

16. D : 300㎜ 5coils
satifaction

17. D : 300㎜ 6coils
satifaction

18. Result 1st In simulation, coil D : 650㎜, 600㎜ results does not satisfy
6.78Mhz band
But, D : 300㎜ result do comparatively satisfy
6.78MHz band
More number of repeating coil is increasing the gain
In 4 coils system, when k approaches the values of 1,
the gain is good, but transmission distance is short

19. The actual experiment D :650㎜

20. Result
In laboratory, we obtained the help and the material, implemented D : 650㎜-2 coil system.
We observed that LED is turned on, it is that power is transmitted.
However, simulation and experiment are actually little different.
D : 300㎜ and 600㎜, We will try to experiment to choose the one case.
In case D : 300㎜, Diameter is small, it is affordable and easy to implement resonant frequency. Of course on simulation.

21. 참고 문헌
인천대학교 Wireless Power Transmission Of Distance Improve For Using Multiple Coils via Coupled Magnetic Resonances 이정근.정영철.고영훈
Design of Resonator-coupledWireless Power Transfer Systemby Equivalent Circuit
Ikuo AwaiRyukoku University

22. Thank you!