Performance assessment of class-E inverter for capacitive power transfer system

Abstract

Purpose This paper aims to present a new wireless power transfer technique using capacitive coupling. The capacitive power transfer (CPT) system has been introduced as an attractive alternative to the traditional inductive coupling method. The CPT offers benefits such as simple topology, fewer components, better electromagnetic interference (EMI) performance and robustness to surrounding metallic elements. Design/methodology/approach A class-E inverter together with and without inductor capacitor (LC) matching circuit has been utilised in this work because of its ability to perform the DC-to-AC inversion efficiently with significant reduction in switching losses. The validity of the proposed concept has been verified by conducting a laboratory experiment of the CPT system. Findings The performances for both systems are analysed and evaluated. A 9.7 W output power is generated through a combined interface [printed circuit board (PCB) plate] capacitance of 2.82 nF at an operating frequency of 1 MHz, with 97 per cent efficiency for 0.25 mm coupling gap distance. Originality value An efficient CPT system with class-E LC matching topology is proposed in this paper. With this topology, the zero-voltage switching can be achieved even if the load is different by properly designing the LC matching transformation circuit.

Capacitive-Wireless Power Transfer System for Power Supply of a Wireless Sensor System on a Propulsion Shaft

“…The design was based on optimized conditions with the duty cycle D at 50%. For that, the circuit has designed the parameters according to References [11,12]. The system parameters for the rotary C-WPT system are shown in Table 1.…”

Cascaded Boost‐Class‐E for rotary capacitive power transfer system

“…In the first block, a Class‐E inverter together with the Δ1b circuit was adapted at the transmitter side to provide the resonant tank with AC excitation. In this design situation, the first Δ1b matching acts as a constant voltage gain network that is to boost or step‐up the voltage across the temporary resistor, R o [19]. It is followed by the LC matching in the second block, which functions to match the final load resistor, R L that is smaller than R o .…”