Dynamic Analysis Of Microscale Piezoelectric Vibration Generating Device And Design Of Micro Power

With the rapid development of microelectronics, micro-machining technology and wireless sensing technology, the embedded systems, radio frequency identification systems and wireless sensor network have been widely used in daily life. The power consumption of these devices is very low and even with the level of microwatts. However, their power supply should be featured with small/micro volume, long life, replacing needless and self-service. Traditional battery can’t satisfy all the demands apparently for its large volume, high weight, the limited energy supply time and other shortcomings. On the other hand, the vibration energy harvester based on MEMS technology can be well integrated with many micro-electronic chips, micro-sensors and micro-actuators. Energy harvester can convert vibrational energy from environment into electrical energy and replace the conventional power source for micro devices, and supply micro-devices with lasting, stable and clean electric energy. At present, the MEMS piezoelectric vibration generator has become the research hotspot of many international research groups due to its broad application.This paper is carried out around the study of MEMS technology of micro piezoelectric vibration generator and its application. The micro electromechanical coupling model of micro piezoelectric vibration generator is established based on the analysis of the domestic and foreign research work. Next the influence of each structural parameter and scale effect on the output performance of the system are analyzed. Also the simulated results and the experimental results are analyzed and discussed.Firstly, the "spring-mass-damper-piezoelectric" electromechanical coupling model is established based on micro piezoelectric vibration generator. However it’s not considering the effects of size reduction on the system, so the scale effect theoretical model is established based on the couple stress theory.Then, the dynamic characteristics analysis is done for the scale of micro piezoelectric vibration generator and the structure parameters and the influence of scale effect on the system are discussed. The voltage power output expressions for the micro system have been inferred. Next, the output of the system characteristics are simulated through the MATLAB and the simulated results in comparison with the laboratory data, the comparative results demonstrated the rationality and the limitations of the existence of the model.Finally, the structure design and the peripheral interface circuit design of the micro power are discussed on the basis of micro piezoelectric vibration generator. And the self powered micro wireless sensor is analyzed based on the application of the micro power. Then the circuit principle diagram of micro sensing system is designed and simulated through the software, the results of the simulation have proved the feasibility of its theory.