The cascaded-magnetic-based energy harvesters, extracting energy from magnetic fields generated from AC current, consist of a clampable core and a high-permeability ungapped core. The clampable core only facilitates a non-intrusive mounting while the high-permeability core guarantees high power extraction. Therefore, reducing the clampable core size could increase power density without drastic power degradation. This article first illustrates the optimization of the clampable core volume based on the harvested power and other design requirements. This paper also presents a method to boost harvested energy by controlling the power transfer window. FEM Simulation and experimental results are shown in this paper.
