This paper proposes a capacitive power transfer system (CPT), which is robust to misalignment of coupling capacitor plates and load variations. The CPT system needs to transmit power at high frequencies. Therefore, it is essentially sensitive to variations in the resonant network, namely resonant component tolerances and load variations. It is required to maintain ZVS and a constant output voltage against these variations. The basic concept of the proposed CPT system is to design the load-independent (LI) resonant dc-dc converter and insert a coupling capacitance into the resonant network. If the coupling capacitance is sufficiently high compared to the resonant capacitance, the variation of the reactance component can be ignored. Therefore, the proposed CPT maintains the LI characteristic, namely, achieving ZVS and constant output voltage against load variations and plate misalignment without requiring control or feedback communication. This paper gives analytical expressions of the proposed system and the design procedure. Experimental results showed the effectiveness of the proposed CPT system along with its design procedure, as well as the validity of the analysis.
- Open Access
- Article
Analysis and Design of Capacitive Power Transfer System with Robustness to Load Variations and Capacitor Plate Misalignment
- Takumi Kobayashi 1,
- Ayano Komanaka 1,
- Tasuku Shuto 1,
- Yasumasa Naka 2,
- Hiroaki Ota 2,
- Yuki Ito 2,
- Hiroo Sekiya (IEICE Fellow) 1,*
Author Information
Received: 18 Jun 2026 | Revised: 23 Jul 2026 | Accepted: 28 Jul 2026 | Published: 07 Aug 2026
Abstract
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