Research On The Reduced-order Modeling Of Micro Electro Mechanical Systems

Micro Electro Mechanical systems (MEMS) are integrative micro-device systems that consist of micro-sensor, micro-actuator, controlling and signal processing circuit, communication interface and electrical source. MEMS has a capacious application future, and its development will engender profound impact on science and technology, ways of production, quality of production and living of human beings. The model and simulation of MEMS can reduce the cost, shorten the design period, optimize the parameter of the system so as to improve the quantity and performance of the product. The simulation of MEMS usually comes down to filed-couple among many physical fields and nonlinearity, so the computation of analysis is very large, and it is urgent to develop simplified and reduced models for MEMS.This dissertation researched on the model and simulation technology for MEMS. At fist, the merits and the demerits of the ways of modeling existed are analyzed. Then a new reduced-order model method, Krylov subspace method is put forward based on the terminal behavior. The terminal behavior method is applied to disintegrate the complex MEMS to simple micro-devices. The next step is to create reduced-order models for micro-devices. With an electrostatic actuated micro-beam with squeeze-film effect as an example, the reduced-order model technology for coupled-field analysis is expatiated. The main research works are:(1) The significance and research state of MEMS modeling technology is studied. Several modeling methods for MEMS are introduced, such as NODAS, VHDL-AMS and equivalent circuits. The merits and demerits of each method are indicated.(2) The theory foundation of terminal behaviors and its application are introduced. The micro-pump system is decomposed into several subsystems by terminal behavior method, and the terminal behavior model of micro-pump system is founded.(3) The application of FEM in two-field coupled analysis of MEMS is studied. The electromechanical coupled micro-device is simulated by ANSYS.(4) The Krylov subspace method with Amoldi approach is introduced. With an electrostatic actuated micro-beam with squeeze-film effect as an example, reduced-order models for coupled-field nonlinear MEMS device is presented. The simulation result shows that the reduced-order models are easy to use and can simulate the system exactly.