Wireless Power Transformation for Data Centers and Medium Voltage Applications

Wireless power transfer (WPT) techniques have been widely explored for various applications including for electric vehicle (EV) and mobile phone charging. Less attention has been paid to the use of WPT for commercial or industrial applications and for power distribution. An isolated wireless power link can enable a touch safe interface without electrically energized contacts eliminating any arc flash or electrocution hazard. This concept can for example enable safe medium voltage distribution inside data centers eliminating low voltage distribution with its large bus bars and cables and bring voltages larger than 1kV directly to the rack. A design methodology is developed for a low loss, high voltage-transfer-ratio wireless power link and a high efficiency medium voltage power converter. The proposed design methodology is evaluated using a 10kW design example and verified by finite element analysis (FEA) and experimental tests. The WPT transformer is developed with a planar magnetics structure. A U-shape ferrite configuration is proposed to improve mutual coupling by providing a low magnetic reluctance coupling path for the magnetic flux. A high efficiency power converter is developed to maintain the output voltage (48V) with a 1kV input over a wide load range. The power transfer efficiency and loss distribution are analyzed.