Design and Analysis of Enhanced Micro-Magnetic Power Receiver

Abstract

An innovative tri-axes micro-power receiver is proposed and studied for wireless magnetic energy transmission. The tri-axes micro-power receiver mainly consists of two sets of 3D micro-solenoids and one set of planar micro-coils in which iron core is individually embedded. The three sets of micro-coils/micro-solenoids are designed to be orthogonal to each other. Therefore, no matter which direction the input magnetic flux is present, the supplied magnetic energy can be harvested and transformed into electric power by the proposed micro-power receiver in wireless sense. By governing equations analysis, based on Biot-Savart's law and Faraday's law, the mathematical description upon power transmission from transmitter to receiver is developed. The estimation error on power transmission by the commercial software Ansoft Maxwell (Ansys, Inc., Canonsburg, Pennsylvania, USA), based on the finite-element method, is revealed in comparison to governing equations analysis method. Besides, the preliminary simulation results by Ansoft Maxwell show that the proposed micro-power receiver can efficiently harvest the energy supplied by the magnetic power source. The design parameters of the tri-axes micro-receiver are hence examined and verified for follow-up fabrication. At last, for the micro-electro mechanical system process, the isotropic etching technique is employed to micro-machine the inverse-trapezoid fillister so that the copper wire can successfully be electroplated. The adhesion between micro-coils and fillister is hence much enhanced as well.