Figures (10)  Tables (3)

    • Figure 1. 

      A typical structure block diagram of the BWPT system.

    • Figure 2. 

      Equivalent circuit of the BWPT system.

    • Figure 3. 

      Phase-shift modulation-based power control strategy for the S–S compensation topology.

    • Figure 4. 

      Diagram of the circuit of the zero-crossing detection.

    • Figure 5. 

      Time sequence diagram of the proposed SR method signal.

    • Figure 6. 

      Operating range of the ZVS conditions. (a) The variation of XS,max with frequency. (b) The range of ZVS.

    • Figure 7. 

      Experimental platform and max efficiency.

    • Figure 8. 

      Soft-switching and synchronous signal. (a) Secondary synchronous signal sampling experimental waveform. (b) Primary waveform. (c) Secondary waveform.

    • Figure 9. 

      Relationship between η and Pout when the Req is 5 Ω.

    • Figure 10. 

      Power loss distribution.

    • Parameters Symbol Value
      Input voltage Uin 12−48 V
      Primary inductance Lp 1.79 μH
      Primary resonant capacitor Cp 15.5 nF
      Primary internal resistances Rp 23 mΩ
      Coil spacing d 10 mm
      Coupling coefficient k 0.32
      Load resistance RL 5 Ω
      Secondary inductance Ls 1.77 μH
      Secondary resonant capacitor Cs 13.5 nF
      Secondary internal resistances Rs 28 mΩ
      Switching frequency fSW 1 MHz
      GaN's output capacitance Qoss 50 nC

      Table 1. 

      System parameters.

    • ZVS boundary conditions Switching frequency (fSW) (MHz)
      φp = 0 0.9034
      φs = 0 0.9582
      XS = XS,max 1.0238
      Network resonance: XS = 0 1.0242

      Table 2. 

      The ZVS boundary conditions and network resonance.

    • Frequency (Hz) Coupling coefficient Output power (W) ηmax Ref.
      360 k 0.75 56 92.5% [27]
      150 k − 46.19 86.4% [33]
      100 k 0.31 1,000 95.5% [30]
      800 k − 35 95.0% [34]
      6.78 M − 15 92.3% [35]
      6.78 M 0.2 17 82% [36]
      120 k 0.8 50 83% [37]
      1 M 0.32 336.57 96.48% This work

      Table 3. 

      Comparison with other works.