A Novel Optimization Method of the DS-LCC Compensation Topology to Reduce the Sensitivity of the Load-Independent Constant Current Output Characteristics to the Component Parametric Deviation

For the double-sided inductor–capacitor–capacitor (DS-LCC) compensation topology, the parametric deviation of compensation elements results in the mismatch between the resonant frequency and operating frequency. Furthermore, this mismatch leads to the loss of the load-independent constant output characteristics. Therefore, an innovative design approach based on the reduction in the capacitance ratio is proposed to attain the load-independent constant current under the parametric deviation. With the presented method, simply by reducing the compensation capacitor ratio, the load-independent constant current output characteristics can be preserved, and fluctuations in the transmission gain caused by the parametric deviation are minimized. This implies that when the constant transmission gain is achieved by the frequency modulation (FM) control, the required FM range can be reduced. Finally, from the experimental results, in the load range of 3 Ω to 33 Ω, compared to the high capacitance ratio, the load-independent constant current characteristics can be maintained at the low capacitance ratio. In addition, without parametric deviation, the transmission efficiencies at different capacitance ratios are basically the same at 93.5% and 94.2%, respectively. However, the transmission efficiencies under different parametric deviations at the low capacitance ratio are 87.4% and 84.9%, but only 73.9% and 68.2% at the high capacitance ratio.