Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System

The performance of a conventional Class-E2-based WPT system is sensitive to system parameters such as the coil coupling coefficient and load variation. System efficiency decreases rapidly when the coil coupling coefficient and load deviate from their optimum values. In this paper, an impedance match...

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Main Authors: Yi Zhang, Yue Feng, Sheng Liu, Jiande Wu, Xiangning He
Format: Article
Language:English
Published: MDPI AG 2021-07-01
Series:Energies
Subjects:
Online Access:https://www.mdpi.com/1996-1073/14/14/4289
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author Yi Zhang
Yue Feng
Sheng Liu
Jiande Wu
Xiangning He
author_facet Yi Zhang
Yue Feng
Sheng Liu
Jiande Wu
Xiangning He
author_sort Yi Zhang
collection DOAJ
description The performance of a conventional Class-E2-based WPT system is sensitive to system parameters such as the coil coupling coefficient and load variation. System efficiency decreases rapidly when the coil coupling coefficient and load deviate from their optimum values. In this paper, an impedance matching method and a design procedure are proposed to maintain high system efficiency over a wider range of coupling coefficient and load variations. The load-pull technique is adopted to identify the high-efficiency load region of a Class-E power amplifier (PA), and a double-L-type impedance matching network (IMN) is proposed to transform the load impedance of a Class-E PA into a high-efficiency working region. Compared to a single L-type IMN, a double-L-type IMN is more flexible and has better tuning performance. A 6.78 MHz Class-E2-based WPT system was built to validate the proposed design method. The experimental results show that the proposed double-L-type IMN can significantly attenuate the decline in Class-E PA efficiency when system parameters dynamically change. With a double-L-type IMN, the WPT system could maintain high efficiency (over 55%) under a wider range of coil coupling coefficient and load variations. The peak system efficiency reached 83.2% with 13.7 W output power. The impedance matching method and design procedure in this paper could provide a practical solution for building a high-efficiency WPT system with strong robustness.
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spelling doaj.art-fa45aa1df7d2471f85826b892dc00d652023-11-22T03:43:11ZengMDPI AGEnergies1996-10732021-07-011414428910.3390/en14144289Impedance Matching Method for 6.78 MHz Class-E2-Based WPT SystemYi Zhang0Yue Feng1Sheng Liu2Jiande Wu3Xiangning He4College of Electrical Engineering, Zhejiang University, Hangzhou 310027, ChinaCollege of Electrical Engineering, Zhejiang University, Hangzhou 310027, ChinaCollege of Electrical Engineering, Zhejiang University, Hangzhou 310027, ChinaCollege of Electrical Engineering, Zhejiang University, Hangzhou 310027, ChinaCollege of Electrical Engineering, Zhejiang University, Hangzhou 310027, ChinaThe performance of a conventional Class-E2-based WPT system is sensitive to system parameters such as the coil coupling coefficient and load variation. System efficiency decreases rapidly when the coil coupling coefficient and load deviate from their optimum values. In this paper, an impedance matching method and a design procedure are proposed to maintain high system efficiency over a wider range of coupling coefficient and load variations. The load-pull technique is adopted to identify the high-efficiency load region of a Class-E power amplifier (PA), and a double-L-type impedance matching network (IMN) is proposed to transform the load impedance of a Class-E PA into a high-efficiency working region. Compared to a single L-type IMN, a double-L-type IMN is more flexible and has better tuning performance. A 6.78 MHz Class-E2-based WPT system was built to validate the proposed design method. The experimental results show that the proposed double-L-type IMN can significantly attenuate the decline in Class-E PA efficiency when system parameters dynamically change. With a double-L-type IMN, the WPT system could maintain high efficiency (over 55%) under a wider range of coil coupling coefficient and load variations. The peak system efficiency reached 83.2% with 13.7 W output power. The impedance matching method and design procedure in this paper could provide a practical solution for building a high-efficiency WPT system with strong robustness.https://www.mdpi.com/1996-1073/14/14/4289impedance matching methoddouble-L-type IMNclass-E2-based WPT system
spellingShingle Yi Zhang
Yue Feng
Sheng Liu
Jiande Wu
Xiangning He
Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System
Energies
impedance matching method
double-L-type IMN
class-E2-based WPT system
title Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System
title_full Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System
title_fullStr Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System
title_full_unstemmed Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System
title_short Impedance Matching Method for 6.78 MHz Class-E2-Based WPT System
title_sort impedance matching method for 6 78 mhz class e2 based wpt system
topic impedance matching method
double-L-type IMN
class-E2-based WPT system
url https://www.mdpi.com/1996-1073/14/14/4289
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AT shengliu impedancematchingmethodfor678mhzclasse2basedwptsystem
AT jiandewu impedancematchingmethodfor678mhzclasse2basedwptsystem
AT xiangninghe impedancematchingmethodfor678mhzclasse2basedwptsystem