Capacitive power transfer technologies are widely researched in recent years. Considering the practical applications, load variation commonly occurs. To solve this problem, this paper proposes a capacitive power transfer system which can realize nearly constant power with wide load ranges. Using a vertical capacitive coupler and designing the double-sided LC topology, the proposed system can realize a nonmonotonic power relationship with different loads. Though this way, the power variation within the required load range decreases so that the adaptation ability of the proposed system is improved. The proposed system, which has the simple circuit structure, has 4% variation of power when loads vary from 30 Ω to 50 Ω. A 2 kW prototype is built to verify the performance of the proposed system.