Evaluation of the Properties of Secondary Side Current Rectifiers for Wireless Power Transfer System

Current tendencies in the field of charging systems are continuously attracted by the phenomenon of the wireless power charging. It is worth to say that within past decade, significant attention was spent on the research and development of various configurations of the transmitters, receivers, compensation networks and alternative solutions for the power circuits on the primary and/or secondary side of the system. In this paper the proposal for the performance optimization of the wireless power transfer (WPT) system is given. The solution is based on the alternative configuration of the secondary side rectifier. It is represented by diode rectifier with current doubler. Comparing to the bridge rectifier, two diodes are replaced by the inductors. Initially, a system analysis was performed to investigate electrical behavior and to find the most optimal conditions referred to terms of efficiency performance at nominal power. Due to this requirement the rectifier inductors must be designed according to meet this condition. The experimental verification was realized as well, while the proposed solution was compared to other common alternatives of the secondary side rectification. The load sensitivity analysis in terms of efficiency performance was realized as well, to observe system behavior for wide operation range. From the results is seen, that proposed alternative of the secondary side rectification of WPT system gives promising results in terms of high operating efficiency.