Design of a Constant-voltage Output Wireless Power Transfer Device

Wireless Power Transfer (WPT) has the advantage of convenience, safety, low-maintenance cost, high reliability and strong adaptability to the environment. In this paper, an inductively coupled wireless power transfer device has been proposed, which consists of H-bridge inverter, loosely coupled transformer, S/LCC compensating circuit, and a closed-loop controlled DC-DC converter. The combination of LCC network and closed-loop converter obtains a precisely constant-voltage output characteristics. To verify the analysis and design, a 100W 50V/50V prototype with a 10cm gap was fabricated and tested and its transmitting efficiency reaches 81.3%.