Development of a real-time power and impedance sensor for wireless power transfer systems

In the field of wireless power transfer technologies, the improvement of transmission efficiency is one of the critical issues. It is important to understand how much power loss is imposed in which areas of a wireless power transfer system in the development phase. Since the transmission characteristics change according to ambient conditions, a measuring instrument capable of observing electric power during power transfer is required. We, Daihen Corporation, have developed a real-time power and impedance sensor useful as a data collection tool in order to improve power transmission efficiency. We have verified, using this sensor, the feasibility of the above objective by optimizing the circuit constants based on measured values obtained during practical power transfer.