Figures (8)  Tables (2)

    • Figure 1. 

      Wireless charging frame for electric wheelchairs. (a) Wireless charging model. (b) The WPT system with dual-side LCC resonant compensation network.

    • Figure 2. 

      Mode analysis of controlled rectifier operation. (a) Pulse phase difference of the rectifier. (b) Modal circuit analysis.

    • Figure 3. 

      Secondary-side impedance analysis. (a) Secondary-side impedance vs the duty cycles of S5 and S6. (b) Secondary-side impedance and the phase angle Uin and I1.

    • Figure 4. 

      Comparison of simulation results of SMC and PI control. (a) M suddenly changes to 18.67 μH. (b) M suddenly changes to 21.33 μH. (c) M suddenly changes to 24 μH.

    • Figure 5. 

      Experimental prototype.

    • Figure 6. 

      Experimental waveforms. (a) Inverter output voltage current and coil current. (b) Controllable rectifier.

    • Figure 7. 

      Offset results. (a) Relation between output current and offset distance. (b) Relation between DC-DC efficiency and offset distance.

    • Figure 8. 

      Power loss ratio of each part of the circuit.

    • ParametersValuesParametersValues
      Udc50 VLs44.9 μH
      C1133.3 nFC4241.2 nF
      C282.2 nFC5100 μF
      L119 μHL210.5 μH
      C376.8 nFL34.7 μH
      Lp49.8 μHRL5.3 Ω

      Table 1. 

      System circuit parameters.

    • Ref. Controlled circuit
      topology      		 Communication Number of converters
      [20] Phase-shifted full-bridge inverter Yes 2
      [21] Secondary-side DC-DC converter No 3
      [22] Primary-side DC-DC converter Yes 3
      [23] Dual-side phase-shift control Yes 2
      This article Controlled rectifier No 2

      Table 2. 

      Comparison with previous controlled circuit topologies.