Control for Maximizing Efficiency of Three-Phase Wireless Power Transfer Systems At Misalignments

抄録

This paper presents a control for maximizing the transfer efficiency of three-phase wireless power transfer systems at misalignments. The control conducts an imbalanced three-phase operation with positive- and negative-sequence components. The positive-sequence component is used to regulate the transferred power, and the negative-sequence component is used to improve the efficiency. The optimal value of the negative-sequence component is determined by a sequential search. A modulation technique for this control allows a three-phase inverter to generate imbalanced voltages required by the control in as few switching numbers as possible. The system employing the control is examined for wireless power transfer of 100W at misalignments of 100mm, the radius of the wireless transfer pad. The tests confirmed the wireless power transfer operation employing the control gains 3% improvement in the efficiency in comparison with a balanced three-phase operation.