Huzaimah Husin

Design of Capacitive Power Transfer Using a Class-E Resonant Inverter

This paper presents a capacitive power transfer (CPT) system using a Class-E resonant inverter. A Class-E resonant inverter is chosen because of its ability to perform DC-to-AC inversion efficiently while significantly reducing switching losses. The proposed CPT system consists of an efficient Class-E resonant inverter and capacitive coupling formed by two flat rectangular transmitter and receiver plates. To understand CPT behavior, we study the effects of various coupling distances on output power performance. The proposed design is verified through lab experiments with a nominal operating frequency of 1 ㎒ and 0.25 ㎜ coupling gap. An efficiency of 96.3% is achieved. A simple frequency tracking unit is also proposed to tune the operating frequency in response to changes in the coupling gap. With this resonant frequency tracking unit, the efficiency of the proposed CPT system can be maintained within 96.3%–91% for the coupling gap range of 0.25–2 ㎜.

Capacitive power transfer with impedance matching network

This paper presents the development of a new wireless power transfer technique using capacitive coupling. Capacitive power transfer (CPT) system has been introduced as an attractive alternative to the traditional inductive coupling method. This is due to the CPT benefits of simple topology, fewer components, better EMI performance and robustness to surrounding metallic elements. In this work, a Class-E resonant inverter together with impedance matching network has been utilized as a high frequency ac power source because of its ability to perform the dc-to-ac inversion efficiently. It helps the CPT system to achieve a maximum power transfer. The CPT system is designed and simulated by using Proteus 8 Professional software. The validity of the proposed concept has been verified by conducting a laboratory experimental CPT system. It generates a 9.5W output power through a combined interface (PCB plate) capacitance of 2.82nF, at an operating frequency of 1MHz, with 95.44% efficiency. Also, the proposed CPT system with impedance matching network allow variation to the load while maintaining the efficiency over 80%.

Development of 416kHz PZT driver for acoustics energy transfer applications

The power transfer efficiency and power transfer capability are the most crucial performance indicator in acoustic energy transfer (AET) applications. As overall efficiency is dependent on the power conditioning at the transmitter and receiver side, it is required to develop a high efficiency power amplifier on the transmitter side in addition with a high efficiency power processor at the receiving end. This paper developed the complete PZT driver with π1a matching impedance circuit that applied to the transmitter unit of the AET system in order to transmit 80mW power on the operating frequency of 416kHz. The Proteus Software used as a simulation platform with peripheral interface controller (PIC16F877A) as pulse width modulation signal generator for MOSFET IRF510 gate in the circuit. As the promising result, the developed transmitter unit shown 73.68mW at 416kHz with 92.1% power conversion efficiency.

Class-E LCCL for capacitive power transfer system

This paper presented the design of a capacitive power transfer (CPT) system by implementing a Class-E inverter due to its high efficiency, which in theory can reach close to 100% performance. However, the Class-E inverter is highly sensitive to its circuit parameters under the scenario of having small capacitance at the coupling plate. As a solution, an additional capacitor can be integrated into the Class-E inverter for increased coupling capacitance for a better performance. Both simulation and experimental investigations were carried out to verify the high efficiency CPT system based on Class-E inverter with additional capacitor. The outcome of the investigation exhibited 96% of overall DC-DC power transfer efficiency with 0.97 W output at 1MHz operating frequency.