Research Of System For MEMS Electret-Based Micro Vibratory Power Generator

With the continuous development of MEMS technology, micro power has become one of the main bottlenecks which cumber the practical application, cost decreasing and automation of MEMS system. The research of micro power is an important part of MEMS technology and has become a hotspot all over the world. The author has overviewed the contemporary research situation of micro power throughout the world, especially analyzed and compared the principles of these micro generators. According to some situation where micro power can't be recharged or replaced, especially to some special requirement of micro power in implanted devices, distributed systems, wireless communications, traffic, micro weapon and aviation, to develop a micro generator system or micro energy conversion device which can be used without the limitation of time, has been an important research program which has a deep academic meaning and an urgent needful background.Supported by the national"863"project, we put forward a novel micro vibratory power generator system, whose main structure consists of two pieces of electret and two combed fingers capacitors based on micro electronics and MEMS technology and so on. After design, analysis and simulation of the micro generator mode, a sample is made and its output power can reach 12.5μW. It will meet the requirement of many vibration circumstances, such as automation control, embedded medical device, wireless net sensor system and micro robot. It is an important research in the attempt to realize the integration of micro power, micro sensor, micro actuator, and low power consumption circuit. We can predict its scientific importance and its wide potential applications.This paper focused on the following aspects:1. Based on scrutinizing and analyzing existing documents, the current development in the area of micro power is analyzed, especially those vibratory ones and electret-based ones.2. The relevant theories of micro electret-based vibratory generator are studied.3. According to the output characteristics of the MEMS micro generator, an energy storage circuit composed of resonance oscillation circuit, commutation circuit and filter circuit are designed, simulated and optimized by the software of OrCAD/Pspice, and then it can be validated by the experiment requirements and through which super-capacitor can be charged. 4. The techniques are developed to fabricate such vibration generator. A prototype is obtained. Its main parameters are given as following, the typical work frequency is 1100Hz, the load resistance is 300k?,the output voltage is 2V and the output power is 12.5μW.5. The experiment system is designed to testify the micro generator samples.,and the testing result is analyzed.X6. An application demonstration experiment of micro generator is accomplished, and the elementary research of practical application has been done.