An electromagnetic, vibration-powered generator for intelligent sensor systems

Abstract

This paper describes the design of miniature generators capable of converting ambient vibration energy into electrical energy for use in powering intelligent sensor systems. Such a device acts as the power supply of a microsystem which can be used in inaccessible areas where wires can not be practically attached to provide power or transmit sensor data. Two prototypes of miniature generator are described and experimental results presented. Prototype A is based around two magnets coupled to a coil attached to a cantilever; prototype B is based around four magnets.For prototype A, experimental results are given for its resonant frequency and its open circuit and loaded output as a function of vibration amplitude. For prototype B, experimental results are given for the generator's Q factor in air and vacuum, its output voltage as a function of vibration amplitude as well as its magnetic field strength. This generator has been tested on a car engine and shown to produce a peak power of 3.9 mW with an average power of 157 W.

Comparison of energy harvesting systems for wireless sensor networks

“…A number of authors have considered electromagnetic vibration energy harvesters ranging from micro electro mechanical (MEM) devices [75−78] to larger scale devices with dimensions of the order of a few centimetres [42,79] . A range of material combinations and magnet/coil configurations have been considered in research devices and a limited number of commercial units developed [80] .…”

A comparative study of electromagnetic generator via finite element element analysis

“…The first configuration consists of two magnets, Fig. 1(a) while the second configuration, Fig 1(b) consists of four magnets [5]. Neodymium Iron Boron magnet was used in his design.…”

“…Meanwhile, the second configuration is able to generating useful power and voltage levels from ambient vibrations. An average power of 157 µW is obtained when a similar device described mounted on the engine block of a car [5]. This paper will investigate different configurations of electromagnetic generator via FEA.…”

Design, fabrication and test of integrated micro-scale vibration-based electromagnetic generator

“…They reported 1 mW of power generated for a 0.24 cm 3 volume at a frequency of 320 Hz. Further, Glynne-Jones et al [4] demonstrated working of an assembled electromagnetic power generator, using fixed bulk magnets and moving wire-wound coil fixed on a stainless steel beam. The generator produced a power of 180 W at a frequency of 322 Hz, acceleration of 2.7 m/s 2 and had a volume of 0.84 cm 3 .…”