Experiments on driving a low-power DC motor by microwave power transfer

The input load characteristics of a DC motor vary with input powers. The conversion efficiency of a rectifying circuit is strongly affected by the connected load. Therefore, to efficiently drive a DC motor using microwave power transfer (MPT), it needs to improve the efficiency-load characteristics of the rectifying circuit. We design a compact power-receiving device which mounts antennas, rectifiers and a buck-boost converter on a multilayer substrate. The buck-boost converter exhibits constant input resistance characteristics independent of the load resistance. Experiments are carried out on driving a low-power DC motor using MPT. High transfer efficiency is achieved between the receiving antenna array and the input of the DC motor. In particular, the measured overall efficiency of the power-receiving device is over 62 % as the power density is changing from 0.25 to 1 mW/cm2.

[1]  Regan Zane,et al.  Power Management System for Online Low Power RF Energy Harvesting Optimization , 2010, IEEE Transactions on Circuits and Systems I: Regular Papers.

[2]  Naoki Shinohara,et al.  Study on direction detection in a microwave power transmission system for a Mars observation airplane , 2014, 2014 IEEE Wireless Power Transfer Conference.

[3]  Naoki Shinohara,et al.  A study on low power rectenna using DC-DC converter to track maximum power point , 2013, 2013 Asia-Pacific Microwave Conference Proceedings (APMC).

[4]  Naoki Shinohara,et al.  Improve the efficiency-load characteristic of rectifying circuit using a self-powered DC-DC converter , 2014, 2014 IEEE Wireless Power Transfer Conference.

[5]  Naoki Shinohara,et al.  A Constant Efficiency of Rectifying Circuit in an Extremely Wide Load Range , 2014, IEEE Transactions on Microwave Theory and Techniques.

[6]  Nobuyuki Kaya,et al.  A Driving Test of a Small DC Motor with a Rectenna Array , 1994 .

[7]  Takehiro Imura,et al.  Basic study on reduction of reflected power using DC/DC converters in wireless power transfer system via magnetic resonant coupling , 2011, 2011 IEEE 33rd International Telecommunications Energy Conference (INTELEC).