A self-powered synchronous magnetic flux extraction interface for electromagnetic energy harvesting

In this work, a self-powered synchronous magnetic flux extraction (SP-SMFE) circuit is proposed for electromagnetic energy harvesting. It's a bridgeless direct ac-dc converter, that uses a large-value external inductor L to store and transfer energy. By comparing the voltage across L, SP-SMFE achieves the peak detection of the inductor current Iem without an external power supply and transfers the energy to the load when Iem reaches the peak value, which can maximize the energy extraction from the electromagnetic transducer. Simulation results show that the output power of SP-SMFE is much higher than that of the voltage doubler circuit under the load range of 1-100 k & omega; and the frequency range of 20-140 Hz. The input ac voltage with 4 V amplitude is rectified and stepped up to 59 V dc by SP-SMFE at the load of 100 k & omega; and the frequency of 40 Hz. Experiment results verify the effectiveness of the SP-SMFE circuit in power harvesting at low frequencies and large loads.

Automated summary

In this work, a self-powered synchronous magnetic flux extraction (SP-SMFE) circuit is proposed for electromagnetic energy harvesting. It achieves the peak detection of the inductor current without an external power supply and maximizes the energy extraction from the electromagnetic transducer.