Demonstration of a basic Finite Element Method Magnetics simulation program *The demonstration is part of exam for FEMM course to operate a basic finite element simulation program took place at Denmark Technical University (2015).

1. Finite Element Simulation
Wireless Power Transfer
Group 2
S100339; S104712

2. Live Example Demonstration
• Software: FEMM 4.2
• Example : Investigating Solenoid
• Solenoid Dimensions:
• R = 1.5 cm
• L = 4.5 cm
• N = 1000

3. Mathematical Comparison
• Inductance:
• Calculation:
• L = 4934.80µH
• Resistance:
• Calculation:
• Voltage Drop:
• Calculations:

4. Mathematical Comparison
• Power:
• Calculation:
• Megnatic Field Energy:
• Energy Stored =
• 0.0025 joules
• B-Field Density:
• Calculation:

5. Wireless Power Transfer
• Axisymetric Model:
• Primary Coil Dimensions: R = 20cm, N = 3, AWG 18,
• Secondary Coil Dimensions: R = 20cm, N = 9, AWG 18,
• FEMM Simulation:
• Demonstrate from FEMM 4.2

6. Wireless Power Transfer
• Simulation Results:

7. Wireless Power Transfer
• Mutual Inductance:
• Flux linkage = 1.78551e-005 Webers = 17.8 µWebers
•
• Couplings Coefitient:
•

8. Wireless Power Transfer
• Planar Model:
• Primary Coil Dimensions: R = 20cm, N = 3, AWG 18
• Secondary Coil Dimensions: R = 20cm, N = 9, AWG 18,
• FEMM Simulation:
• Demonstrate from FEMM 4.2

9. Wireless Power Transfer
• Simulation Results:

10. Mathematical Comparison
• Primary Resistance:
• Calculation: R = 0.07 Ω
• Primary Voltage:
• Calculation: V = I*R = 0.205 * 0.207 = 0.0140 V = 14mV
• Primary Power:
• Calculation: P = V* I = 0.0028 watt = 2.8mW
• Primary Inductance:
• Calculation : 10 µH

11. Mathematical Comparison
• Primary Magnetic field ”B”:
• Calculation: B = u0*n*itotal = (1.2556e-006*0.6 = 6.5745e-007
• U= 4*pi*10^-7
• n= N/L
• Itotal = 0.6
• Resonans Frequency
• Calculation:

12. Mathematical Comparison
• Secondary Resistance:
• Calculation : 0.213Ω
• Secondary Inductance:
• Calculation: 61.8µH
• Secondary Voltage:
• Calculation: 0.042 V = 42mV
• Resonance Frequency:
• Calculation:

13. LT Spice Simulation
• Q factor for primary
• Q=f0/delta=212796/1300=163.68

14. LT Spice Simulation
• Q factor for sacondary
• Q=f0/deltaf=212000/800=265

15. LT Spice Simulation
• Circuits

16. LT Spice Simulation
• Output for secondary

17. LT Spice Simulation
• Input to primary

18. Oscilliscope Measurements
• Primary Voltage:

19. Oscilliscope Measurements
• Primary Current:

20. Oscilliscope Measurements
• Secondary Voltage:

21. Oscilliscope Measurements
• Secondary Current:

22. Matlab Script

23. Matlab Script

24. Matlab Script

25. Matlab Script