Layout Optimization of Printed Planar Coil with Variable Trace Width and Spacing

Printed planar coil in standard manufacture is commonly used in the wireless power transmission (WPT) systems. Improving coils' quality factor is one of important ways to make WPT more efficient. Varying the trace width and turn-to-turn spacing in a new layout method is proposed to optimize the quality factor of planar coils. An analytical model comprising the parasitic resistance and capacitance is also established. The proposed method and the model are verified to be effective through simulations and experiments.