Research On Vibration Energy Capturing Based On Mechanical-Electrical Coupling Materials

In order to promote the application of mechanical electrical coupling materials and structures, and to boost its application to a new level, we need immediately to resolve the simulation problem of its inner nonlinear dynamics. So how to construct a differential model of hysteresis to suit engineering application is now becoming a basic scientific issue in related application researches of energy capture.In this article, piezoelectric and ferroelectric cantilever beam are the object of study, and the researches of hysteresis dynamic associated with domain switching in ferroelectric materials and composite structures and the research about vibration energy capture also have a direct and valuable reference to the research of other smart materials and structures. The main contents of this article:1. Based on the research status of vibration energy of mechanical electrical coupling materials both at home and abroad, the author summarizes and analyzes the key science and technology problems to determine the research ideas of this article.2. This article gives a detailed description of the domain structure of ferroelectric material and the orientation switching, and also introduces the ferroelectric phase transition according to thermodynamic theory. Also, based on Landau theory of phase transitions, construct a new differential constitutive model of ferroelectric material. With this model, hysteresis loop and double-hysteresis loop of ferroelectric materials are simulated successfully.3. Based on the bending static equation of Euler-Bernoulli beam, this article constructs a bending static equation of ferroelectric and piezoelectric cantilever beam and using Comsol Multiphysics software to simulate the piezoelectric cantilever beam and simulate the deflection when the free end receives 100N and 50N force respectively, to obtain a direct ratio between force and deflection of the free end.4. Vibration test bench of mechanical electrical coupling structure is built, and also design a digital acquisition system of this test bench based on labview software.5. Using vibration test bench of mechanical electrical coupling structure to do the experiment on vibration energy capture of ferroelectric and piezoelectric cantilever beam, and compares the charges produced under different excitation frequencies and amplitudes of ferroelectric and piezoelectric cantilever beam.6. Making a conclusion of what have been done in this paper first, and then point out the shortage in this article, for example, because the driving amplitude is so small that ferroelectric cantilever beam cannot get a bigger loading. So it cannot let ferroelectric material have orientation switching. And also need to improve the type of ferroelectric and piezoelectric materials to compare the experiment data more conveniently.