A novel power extraction technique for AC/DC boost for force-driven magnetostrictive energy harvesters

In this paper, a novel technique for the control of an AC/DC boost converter aimed at efficiently extracting power from magnetostrictive vibration energy harvesters (MVEHs) is proposed and experimentally tested. The proposed Inductor Current Multi Peaks (ICMP) technique automatically detects the optimal turn ON/OFF of the converter switches. In this way the MVEH internal inductance is charged/discharged multiple times per period, with a consequent increase of the extracted power with respect to the state-of-the-art techniques (characterized instead by only two charge/discharge cycles per period). Moreover, the ICMP technique avoids the need for a maximum power point tracking function by extracting maximum power over a large interval of DC voltage values. Experimental tests of a proof-of-concept prototype confirm the theoretical findings and the predicted behavior.