Class E resonant low dv/dt rectifier

Qiao

IEEE Trans. Power Electron.

et al. 2017

Wireless power transfer (WPT) working at megahertz (MHz) is widely considered a promising technology for midrange and low-power applications. A Class E 2 dc-dc converter is composed of a Class E power amplifier (PA) and a Class E rectifier. It is attractive for applications in MHz WPT due to the soft-switching properties of both the PA and the rectifier. Using the existing design the Class E 2 dc-dc converter can only achieve optimal performance such as a high efficiency under a fixed operating condition. Meanwhile, in real applications variations in the coil relative position and the final load are common. The purpose of this paper is to analyze and develop a general design methodology for a robust Class E 2 dc-dc converter in MHz WPT applications. Component and system efficiencies are analytically derived, which serve as the basis for the determination of the design parameters. The classical matching network of the Class E PA is also improved that provides the required impedance compression capability. Then a robust parameter design procedure is developed. Both the experimental and calculated results show that proposed design approach can significantly improve the robustness of the efficiency of the Class E 2 dc-dc converter against variations in coil relative position and final load. Finally, the experiments show that the range of variation of the system efficiency is narrowed from 47.5%-85.0% to 73.3%-83.7% using the proposed robust design.Index Terms-Wireless power transfer, Class E 2 dc-dc converter, efficiency, matching network, robust analysis and design.

Section: Parameter Design Proceduresmentioning

confidence: 99%

“…The efficiency of the overall MHz WPT system, η sys , can be obtained through the multiplication of (12), (17), and (19).…”

Section: Class E Rectifiermentioning

confidence: 99%

Analysis and Design of A Robust Class $E^2$ DC–DC Converter for Megahertz Wireless Power Transfer

Qiao

IEEE Trans. Power Electron.

et al. 2017

IEEE Trans. Power Electron.

“…Consequently, the rectifier circuit needs to appear inductive to the input voltage at each harmonic to ensure a near sinusoidal input current. In order to create a design process similar to that of the Class-E rectifier in [19], the value of L 1 can be set to resonate with C 1 at the fundamental switching frequency, i.e.,…”

Section: B Input Impedancementioning

confidence: 99%

“…Various configurations of the Class-E rectifier were also introduced in [18]. A particular Class-E rectifier configuration that is of interest in WPT is the voltage-driven Class-E resonant low dv/dt rectifier introduced in [18] and analyzed in detail in [6] and [19]. This rectifier configuration consists of a single diode, a shunt capacitor, and an inductor at its terminal.…”

Section: Introductionmentioning

confidence: 99%

Design and Development of a Class EF$_2$ Inverter and Rectifier for Multimegahertz Wireless Power Transfer Systems

Aldhaher

Yates

Mitcheson

2016

This paper presents the design and implementation of a Class EF 2 inverter and Class EF 2 rectifier for two-W wireless power transfer (WPT) systems, one operating at 6.78 MHz and the other at 27.12 MHz. It will be shown that the Class EF 2 circuits can be designed to have beneficial features for WPT applications such as reduced second-harmonic component and lower total harmonic distortion, higher power-output capability, reduction in magnetic core requirements and operation at higher frequencies in rectification compared to other circuit topologies. A model will first be presented to analyze the circuits and to derive values of its components to achieve optimum switching operation. Additional analysis regarding harmonic content, magnetic core requirements and open-circuit protection will also be performed. The design and implementation process of the two Class-EF 2-based WPT systems will be discussed and compared to an equivalent Class-E-based WPT system. Experimental results will be provided to confirm validity of the analysis. A dc-dc efficiency of 75% was achieved with Class-EF 2-based systems. Index Terms-Class-EF inverters, class-EF rectifiers, wireless power transfer (WPT).

2014 IEEE Energy Conversion Congress and Exposition (ECCE)

“…Resonant rectifiers have been explored in a variety of contexts [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25]. The traditional design of a class E rectifier, or shunt-loaded resonant rectifier, utilizes a (large) choke Figure 1.…”

Section: Introductionmentioning

confidence: 99%

Design of Class E resonant rectifiers and diode evaluation for VHF power conversion

Santiago-González¹,

Elbaggari²,

Afridi³

et al. 2014

Abstract-Resonantrectifiers have important applications in very-high-frequency (VHF) power conversion systems, including dc-dc converters, wireless power transfer systems, and energy recovery circuits for radio-frequency systems. In many of these applications, it is desirable for the rectifier to appear as a resistor at its ac input port. However, for a given dc output voltage, the input impedance of a resonant rectifier varies in magnitude and phase as output power changes. This paper presents a design methodology for class E rectifiers that maintain near-resistive input impedance along with the experimental demonstration of this approach. Resonant rectifiers operating at 30 MHz over 10:1 and 2:1 power ranges are used to validate the design methodology and identify its limits. Furthermore, a number of Si Schottky diodes are experimentally evaluated for VHF rectification and categorized based on performance.