Wireless Energy Transmission System with Primary Side Control Method

• Main Authors: Tso-Sheng Chan, 詹作晟
• Other Authors: 陳秋麟
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/17247945574571848339

博士 === 國立臺灣大學 === 電子工程學研究所 === 100 === This dissertation presents a low power wireless energy transmission system (WETS) with the primary side control method. The WETS has no physical wire connection required between the primary and secondary-side circuits. The primary side control method implemented in the WETS does not require extra space in the secondary side to regulate transmission energy. A charging protection is embedded within the secondary side to monitor the charging current and battery voltage, and to protect the battery against over-charging current or voltage. LLC resonant converter and class-E power amplifier structures with zero voltage switching are utilized to minimize transmission loss due to leakage inductance. According to experimental results, the secondary side battery is fed a stable charging current in current mode and low current in voltage mode where the battery voltage reached approximately 4.1V. The results show that the WETS achieved primary side control in all air-gap conditions. The overall efficiency of the WETS with LLC resonant converter is between 33.5 % and 54.1 %, and that of the class-E amplifier is between 30 % and 66.2 % when operating in the current mode. The efficiency of the secondary-side protection circuit is 86.5 %, and the quiescent current of secondary-side protection circuit is 20μA when the WETS does not work.