| Micro Electro Mechanical Syetem (MEMS) is a new and developing forward research field which arose in the late-,1980s. At present,as a new and high technique and a potential huge industry,MEMS has received much attention from various coutries in the world and many research and industial organizations are engaging in broad and deep studies in MEMS. MEMS is a kind of independent micro mechanical and electric(or electronic)system,it is composed of several parts such as microactuators,microsensors,microexecuators,micro source of energy etc. As a typical kind of microactuators,micromotors have been the hot field in MEMS research,it is believed that the technical level of micromotors reflects the developing level of MEMS of a country in some extent. Magnetic micromotors have many advantages that other type of micromotors do not have,and is one of the most prospective microactuators. In the latest years,people have designed and made many types of magnetic micromotors,but there are still many problems and much work which needs to do about the working principal,design theory and experimental research of magnetic micromotors,This dissertation was just aimed at these problems and did following work:First,on the basis of analying and comparing the working principals and structures of available magnetic micromotors,this dissertation proposed a new type of magnetic micromotor,introduced its structure,controlling methods and the features. According to the basic principles of the fixed-point movement of the rigid body,the dissertation revealed the moving relationship between the rotation of the inner magnetic field of the motor and the rolling of the rotor,presented the moving equation of the rotor and the calculation formula for the rotation ratio between the the inner magnetic field and the rotor,and so made clear the relationship between the structure parameters and the moving characteristics of the motor.Next,in order to comprehand the electromagnetic characteristics and the dynamic characteristics of the new type of magnetic micromotors,the dissertation applied the concept of the magnetic scarlar potential of the irrotational magnetic fields and set up the mathmatic model for the inner magnetic field of the new type of motors from the basic equations and the boundary conditions of the motor magnetic field. Oh the basis of the mathmatic model,the dissertation analized the various qualities of the magnetic field of the air gap between the rotor and the stator and gave a detailed calculation of the air gap's magnetic potential,magnetic field intensity,magnetic induction,the shape of the magnetic scarlar potential level surface,the distribution of the magnetic circuit,the magnetic inductionthe self-inductance and the mutual inductance of the coils.Then,from the basic energy conversion theory of the electricmechanical system,the dissertation revealed the energy relationship and the energy conversion mechanism in the new type of magnetic micromotors,discussed such two important factors as the electromotive force and the electromagnetic torque which are essential to realize the conversion between the mechanical energy and the electric energy,established the motor system's moving equation and the calculation formula for the rotor's output torque under different controlling conditions. Further more,through the calculation formula for the motor's output torque,the dissertation analized the relations between the motor's various parameters(including structure and controlling parameters) and the output torque of the rotor,discussed the qualities and the changing features of the motor's output torque,and so established a firm theoretical basis for analizing and designing the new type of micromotors.Last,the author successfully made a 5mm experimental prototype of the new type of micromotors and carried out a serials of kinematic and dynamic experiments which verified the theoretical system put forward in the dissertation,and so established an important foundation for the application study of the new type of magnetic... |
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