SGER: Fundamentals of Kinetic to Electrical Energy Conversion via Magnetic Fluids

虽然有几种环境能源适合于能量收集应用，包括太阳能、热能和动能，但由于振动无处不在，机械振动能量收集通常是最吸引人的。然而，环境振动是在低频率范围（200赫兹）。这使得基于谐波振荡器方法的高效微尺度变换器的开发变得困难，因为这些器件的基频要高几个数量级。本研究概述的研究重点是通过磁流体（液体中磁性颗粒的悬浮液）将动能转换为电能的新概念的概念验证演示。这个想法是利用由机械振动引起的液体运动来驱动悬浮在液体中的磁性粒子集合的净磁矩的周期性变化。在提出的能量收集机制中，液体运动随磁矩周期性旋转粒子，集体效应在附近线圈中产生电动势。为了提供集体效应，通过将流体置于均匀的磁场中来获得流体中颗粒的磁矩的对齐。无线、自主传感器网络可以在许多应用中实现连续、无孔不入的监测和控制，如设备诊断和控制、机动车辆、飞机和结构监测、活体、实时生物医学监测、智能服装以及情报和监视操作。此外，无线传感器和执行器的一个迅速兴起的应用是至关重要的是家庭自动化网络，其中它们在电力消耗管理中起着关键作用。成功实施任何微传感器网络的关键是开发本地微尺度能源，为单个传感器/执行器提供电力，因为在许多情况下使用电池不是可行的解决方案。

CBET-0813598Borca-TasciucAlthough there are several ambient energy sources suitable for energy scavenging applications including solar, thermal and kinetic energy sources, mechanical vibration energy harvesting is often most appealing as vibrations are ubiquitous. However, environmental vibrations are in the low frequency range (200 Hz). This makes difficult the development of efficient microscale converters based on the harmonic oscillator approach since the fundamental frequency of these devices is orders of magnitude higher. The research outlined in this study focuses on proof-of-concept demonstrations of a novel concept for kinetic to electrical energy conversion via magnetic fluids (suspensions of magnetic particles in a liquid). The idea is to employ the motion of a liquid induced by mechanical vibrations in order to actuate a periodic change in the net magnetic moment of a collection of magnetic particles suspended in the liquid. In the proposed mechanism of power harvesting, the liquid motion periodically rotates the particles along with their magnetic moment and the collective effect gives rise to an electromotive force in a nearby coil. To provide the collective effect, alignment of the magnetic moments of the particles in the fluid is obtained by subjecting the fluid to a uniform magnetic field. Wireless, autonomous sensor networks could enable continuous, pervasive monitoring and control in numerous applications such as equipment diagnostic and control, motor vehicle, plane and structure monitoring, in-vivo, real time biomedical monitoring, smart clothing as well as intelligence and surveillance operations. Furthermore, a rapidly emerging application of wireless sensors and actuators which is of critical importance is home automation networks, where they play a key role in the management of power consumption. Essential to the successful implementation of any microsensor network is developing local, microscale energy sources to provide electrical power to individual sensors/actuators, since in many cases using batteries is not a viable solution.