Circular Capacitive Coupler With Multilayer Interleaving for Stable Output

Capacitive power transfer (CPT) is able to utilize the benefits of electric field and offers an alternate wireless charging solution. However, the basic capacitive couplers usually suffer from the misalignment issue. The coupler parameter shift leads to dramatic output perturbation. In order to stabilize the output, three types of coupling (mutual, self, and cross) are defined to simplify the coupler structure evaluation, and a circular capacitive coupler (CCC) is optimized to stabilize the mutual coupling under various movements. Furthermore, the multilayer interleaving is applied the circular coupler to enhance the self-coupling and minimize the cross coupling. The final experiment implements a series compensated system with the proposed coupler. The output current variation is less the 3.5% within the charging area.