Study On Oscillation Of Large-scale Turbo-generator Stator System Under Hamilton Canonical Equation System

A lot of potential problems may be encountered with enhancement oflarge-scale generator capability. Most of all is vibration problem when generator is operating. To research and predominate the oscillation law of large-scale generator is premises to increase the security and reliability. Therefore, it is necessary to employ new theory, new approach in mechanics and combine with electromagnetism to make a thorough study on the oscillation problem oflarge-scale generator. In the thesis, a laminated model of the stator core and double-shell model of stator system are established. Based on Hamilton canonical equation system and its semi-analytical solution, a characteristic equation of the laminated model of the stator core, double-shell model of stator system and dynamic coupling equation of the double-shell model are derived. Not only Hamilton canonicalequation system but also analytical procedure (semi-analytical solution) isintroduced into dynamic behavior research of large-scale generator firstly. The main work can be outlined as follow: 1. The limited model of stator core is the first to be established. It is not necessary to simplify the stator core heavily. The assumption, which the stator core is the isotropy continuum and made of even material, is not necessary, and the difficult problem that the elastic modulus of stator core is not easyconfirmed, is solved. The example testifies the model reliable. The Hamilton canonical equation system and semi-analytical is the basis of natural behavior analysis of laminated model and double-shell model. 2. The natural behavior analysis equation of double-shell model is derived from the Hamilton canonical equation of cylindrical shell, and it is the basis of analyzing free frequencies of stator system and the effect of electromagnetic rigidity on free frequencies of stator system. There are two advantages in the equation. Firstly, because the method of transfer matrix is employed, thethickness of shells is not restricted in the equation. Secondly, because of the semi-analytical solution, the equation is suitable forcomplex boundary 3 第一章绪 论 conditions, therefore, the natural behavior of double-shell analysis method in the thesis can be used widely in engineering. 3. Expressions of Maxwell magnetic stress are derived from expressions of the electric current of stator and rotor. Electromagnetic rigidity expressions are obtained under considering the reciprocity of vibration displacement of stator core and electromagnet field. The analysis method of electric currentI R and included angle . between the dominant wave peak of electric current of rotor and the dominant wave peak of electric current of stator are produced by electric current of the output power. The effect of electromagnetic rigidity on free frequencies of stator system is analyzed. 4. Dynamic coupling equation of the double-shell model is produced according to the Hamilton canonical equation of the cylindrical shell and the Wilson-è method. The vibration law of a turbo-generator stator system with the load is analyzed with dynamic coupling equation of the double-shell model. The result is that the amplitude of vibration of turbo-generator stator system reduces with the increase of output power when cos. equals 0.85. The result can be used as the theoretic...