Table 3 Comparison of coupling coefficient (k) and mutual inductance (M) for different thickness of ferrite shielding of coil with different air gaps

0

0.29817

11.9139

40.00

5

0.47226

35.1383

74.34

10

0.53017

41.3085

78.00

15

0.59048

48.2171

81.60

50

20

0.65458

56.5240

86.30

25

0.72197

66.9508

92.70

30

0.79084

80.5109

101.70

35

0.85857

99.0489

115.31

40

0.92125

127.4293

138.34

45

0.97293

177.5978

182.40

0

0.19582

8.1322

41.54

5

0.2917

20.65681

70.92

10

0.32683

23.71778

72.61

15

0.36408

26.92272

73.97

100

20

0.40487

30.53601

75.39

25

0.44928

34.69088

77.15

30

0.49803

39.50752

79.37

35

0.5511

45.18491

81.94

40

0.60834

52.02325

85.46

45

0.66944

60.41944

90.27

0

0.13228

5.5706

42.04

5

0.18565

12.96439

69.81

10

0.20691

14.70779

71.02

15

0.22953

16.49878

71.87

Rectangular

150

20

0.25421

18.46125

72.51

25

0.28137

20.64115

73.29

30

0.31124

23.07157

74.12

35

0.34402

25.83776

75.13

40

0.38005

28.98805

76.35

45

0.41978

32.58788

77.69

0

0.09154

3.87767

42.29

5

0.12183

8.47255

69.50

10

0.13505

9.52868

70.45

15

0.14903

10.61717

71.20

200

20

0.1643

11.783

71.77

25

0.18088

13.06014

72.20

30

0.19921

14.46152

72.64

35

0.21932

16.02393

73.30

40

0.24145

17.75982

73.43

45

0.26576

19.70046

73.88