This paper proposes a 6.78 MHz four-plate capacitive power transfer (CPT) system for wireless charging applications of unmanned aerial vehicles (UAVs). To address the issue of non-uniform edge electric field distribution in conventional systems, a large area transmitting plate with dimensions of 500 mm × 500 mm is designed, integrating a mesh structure to optimize edge effects and reduce overall weight. Finite element electric field simulations verify that the variation rate of the coupling capacitance CM remains within 15% as the receiving plate moves to any position within the transmitting plate’s area, effectively achieving a free-positioning characteristic. Based on this, an LCL-PS compensation topology is selected for its simple structure and ease of integration. This topology exhibits an output power that is proportional to the system’s operating frequency, which is advantageous for enhancing power transfer under high-frequency conditions. Finally, system modeling and simulation confirm that the CPT system can stably deliver an output power of 210 W at an operating frequency of 6.78 MHz, validating the feasibility of the proposed solution.