The present invention describes systems and methods for harvesting energy from an alternating magnetic field. An exemplary embodiment can include a flux concentrator having an open core coil wherein a first current with a first voltage is induced in the flux concentrator when placed proximate an alternating magnetic field. Additionally, the system can include a transformer, having a first and second winding, connected to the flux concentrator and inducing a second current in the second winding, wherein the second current has a second voltage higher than the first voltage and a threshold voltage of a first and second diode. Furthermore, the system can include a converter, connected to the secondary winding for charging the leakage inductance of the secondary winding by creating a short circuit between the secondary winding and the converter; and the diodes connected to the secondary winding and the converter for discharging the leakage inductance.