Wireless Power Transfer Technology Via Coupled Magnetic Resonances For Embedded Fault Diagnosis System

Energy-supply is a bottleneck of embedded fault diagnosis system, which is supplied traditionally with battery with the annoyance of its limited capacity. As a new concept of energy transmission, wireless power transfer technology via coupled magnetic resonances (WiTricity) is very promising since it overcomes lots of shortages of traditional electric energy transmission and transmits fairy energy in moderate range of distance. In this paper, WiTricity technique is firstly introduced to embedded fault diagnosis system to solve its energy-supply problem. The main contents and conclusions of this thesis are as follows:1. Research theory of coupled magnetic resonances and analyze the conditions of energy transmission and the effect of the coil parameters. Build the mutual induction model of wireless energy transmission based on WiTricity. The relationship between transmission efficiency and coil size, natural frequency and distance is researched and efficient method for improving transmission efficiency is obtained.2. Using the software ANSYS we simulate the magnetic field urged by single helix coil and carry out simulation for the coupling magnetic field between a couple of helix coils. The relationship between coupled magnetic field and coil radius, coil distance and receiving coil radius is compared and analyzed.3. Design and make one-to-one wireless energy transmission device which contains signal generation circuit, power amplification circuit, resonance emission circuit, rectifier circuit and load part. Around 1MHz, we succeed in lightening the bulb (220V/15W) in the range of 20cm and validate the feasibility of wireless energy transmission device. We design a group of experiments with different parameters and carry out comparative trial, and then analyze the effect of different parameters to transmission characteristic.4. The method of multidirectional magnetic resonance energy transmission is presented. Magnetic resonance electric energy transmission is sensitive to the direction of transmission. Propose and design the resonance coil with three dimensional structures and the direction independence of receiving end is improved efficiently. On the basis of one-to-one transmission pattern, we study the one-to-many transmission pattern and design the experimental transmission device.