Figures (23)  Tables (7)
    • Figure 1. 

      Basic structure of the copper-foil electromagnetic coupler. (a) 3D graph of the coupler. (b) Front view[22].

    • Figure 2. 

      Circuit topology of WPT system without compensation.

    • Figure 3. 

      System π-type equivalent model.

    • Figure 4. 

      Controlled source equivalent circuit.

    • Figure 5. 

      System T-type decoupled model.

    • Figure 6. 

      Top view of the single coil.

    • Figure 7. 

      Variation of the input impedance with Nin and Req[22].

    • Figure 8. 

      Ground-referenced voltage curve of P3 and P4[22]. (a) f = f1. (b) f = f2.

    • Figure 9. 

      Variation of magnetic-field and electric-field coupling coefficient.

    • Figure 10. 

      The variation of coupling coefficient with win and wout (or sin and sout).

    • Figure 11. 

      The variation of the system resonance frequency f1 with win and wout (or sin and sout).

    • Figure 12. 

      The variation of kIPT with ds and dt.

    • Figure 13. 

      The variation of kCPT with ds and dt.

    • Figure 14. 

      The variation of f1 with ds and dt.

    • Figure 15. 

      Simulation waveforms of inverter output voltage and current.

    • Figure 16. 

      Simulation waveforms of system output voltage varying with Req.

    • Figure 17. 

      (a) Electric field distribution around the coupler. (b) Magnetic field distribution around the coupler.

    • Figure 18. 

      Experimental prototype of the WPT system.

    • Figure 19. 

      Experimental waveforms of the inverter output and the AC load voltage.

    • Figure 20. 

      Experimental waveforms of the DC load voltage when RL changes (100→50→25 Ω).

    • Figure 21. 

      The experiment results shown in power analyzer.

    • Figure 22. 

      Loss distributions of the experimental prototype.

    • Figure 23. 

      (a) Test output power of the misalignment ability for this WPT system. (b) Experimental efficiency of the misalignment ability for this WPT system.

    • System
      parameters
      First ZPA condition Second ZPA condition
      Operating angular frequency $ \omega  \text{=}\sqrt{\dfrac{{C}_{\text{A}}\text{+}{C}_{\text{B}}}{\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\text{+}{L}_{\text{M}}\right){C}_{\text{A}}{C}_{\text{B}}}} $ $ \begin{cases} {\omega }_{1}\text{=}\sqrt{\dfrac{-B+\sqrt{{B}^{2}-4AC}}{2A}}\\{\omega }_{2}\text{=}\sqrt{\dfrac{-B-\sqrt{{B}^{2}-4AC}}{2A}}\end{cases} $
      Input
      impedance
      $ {Z}_{\text{in}}\text{=}\dfrac{{\left(\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right){C}_{\text{A}}-{L}_{\text{M}}{C}_{\text{B}}\right)}^{2}}{\left({L}_{\text{M}}+{L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)\left({C}_{\text{A}}+{C}_{\text{B}}\right){C}_{\text{A}}{C}_{\text{B}}{R}_{\text{eq}}} $ $ {R}_{\text{eq}} $
      Output
      voltage
      $ {\dot{U}}_{\text{out}}=-j{\dot{U}}_{\text{in}}{R}_{\text{eq}}\dfrac{\sqrt{\left({L}_{\text{M}}+{L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)\left({C}_{\text{A}}+{C}_{\text{B}}\right){C}_{\text{A}}{C}_{\text{B}}}}{\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right){C}_{\text{A}}-{L}_{\text{M}}{C}_{\text{B}}} $ $ {\dot{U}}_{\text{out}}=-{\dot{U}}_{\text{in}}\cdot \dfrac{{\omega }^{2}{C}_{\text{A}}\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)-1\text{+}j\omega {C}_{\text{A}}{R}_{\text{eq}}}{{\omega }^{2}{C}_{\text{A}}\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)-1-j\omega {C}_{\text{A}}{R}_{\text{eq}}} $
      Output
      current
      $ {\dot{I}}_{\text{out}}=-j\dfrac{\sqrt{\left({L}_{\text{M}}+{L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)\left({C}_{\text{A}}+{C}_{\text{B}}\right){C}_{\text{A}}{C}_{\text{B}}}}{\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right){C}_{\text{A}}-{L}_{\text{M}}{C}_{\text{B}}} {\dot{U}}_{\text{in}}$ $ {\dot{I}}_{\text{out}}=-\dfrac{{\dot{U}}_{\text{in}}}{{R}_{\text{eq}}}\dfrac{{\omega }^{2}{C}_{\text{A}}\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)-1\text{+}j\omega {C}_{\text{A}}{R}_{\text{eq}}}{{\omega }^{2}{C}_{\text{A}}\left({L}_{1\text{M}}\text{+}{L}_{\text{2M}}\right)-1-j\omega {C}_{\text{A}}{R}_{\text{eq}}} $

      Table 1. 

      System parameters in two ZPA conditions.

    • ParameterValueParameterValue
      Nout15dt60 mm
      sout5 mmsin5 mm
      ds10 mmwout10 mm
      win10 mm

      Table 2. 

      Parameters of the coupler when Nin is variable.

    • Parameter Value Parameter Value
      Nout 15 Nin 9
      sout + wout 15 mm dt 60 mm
      ds 10 mm sin + win 15 mm

      Table 3. 

      Parameters of the coupler when sout and wout are variable.

    • Parameter Value Parameter Value
      Nout 15 Nin 9
      sout 5 mm sin 5 mm
      wout 10 mm win 10 mm
      Req 40 Ω

      Table 4. 

      Parameters of the coupler when ds and dt are variable.

    • ParameterValueParameterValue
      Nout15Nin9
      sout5 mmsin5 mm
      wout10 mmwin10 mm
      ds10 mmdt60 mm

      Table 5. 

      Geometric parameters of the coupler.

    • Parameter Value Parameter Value Parameter Value
      f 1.056 MHz M12 22.731μH C12 324.98 pF
      Udc (Uin) 78.54V
      (100 V)
      M13 28.369 μH C13 30.376 pF
      RL (Req) 49.348 Ω
      (40 Ω)
      M14 12.367 μH C14 3.0998 pF
      L1 64.622 μH M23 12.366 μH C23 3.1395 pF
      L2 19.517 μH M24 7.2848 μH C24 13.198 pF
      L3 64.407 μH M34 22.722 μH C34 324.14 pF
      L4 19.432 μH

      Table 6. 

      Circuit parameters for simulation.

    • ParameterValueParameterValue
      UP1-G100 VUP2-G100 V
      UP3-G170.9 VUP4-G72.24 V
      IP12.484 AIP22.484 A
      IP32.475 AIP42.475 A

      Table 7. 

      Amplitude value of the voltage to ground and current of P1−P4.