12 th International Research/Expert Conference “Trends in the Development of Machinery and Associated Technology” TMT 2008, Istanbul, Turkey, 26 - 30 August 2008 GENERAL DYNAMIC MODEL OF THE TURBOGENERATOR RELATED TO THE TYPE OF SUPPORT Dr. Sc. Shaban A. Buza, Dr.Sc. Xhevat Perjuci, Dr. Sc. Kastriot A. Buza, Dr. Sc. Fevzi Radoniqi Faculty of Mechanical Engineering Prishtina, Kosova Dr. Sc. Nysret Avdiu Faculty of Electrical and Computing Engineering Prishtina, Kosova ABSTRACT Turbogenerator as a set of turbines and electric generator presents a very complicated mechanical system. Its design must take into consideration the rotordynamics of rotor, which undergoes bending and torsional oscillation. The oscillation of the rotor depends upon its geometry and type of support. In this paper the dynamic models for the turbogenerator with three turbines and an electric generator supported in different types of bearings has been analysed. The mathematic model was extended with electromagnetic moment and the resistant moment of the working machine. The adopted models – mechanical and its mathematical - are a good base for dynamic analysis at the different types of turbogenerators. Key words: Turbogenerator, Turbine, Electric Generator, Bending and Torsional Oscillation 1. INTRODUCTION The engineering components concerned with the subject of rotordynamics are the rotors of machines, especially turbines and generators known as turbogenerators. Turbogenerators as complicated machines that are used to develop power, consist of several turbines (gas and/or steam) coupled to the electric generator. During the rotating machines design analysis of the torsional oscillations are of vital importance, but in this paper a general model was built including also bending oscillations. Adopted model includes oscillations of the elastic shaft depending upon its geometry, number of disks assembled on it, the type of support (bearings and foundation) and as well as on excitation forces. Gyroscopic effect as the inertia-related moment in an angular lateral motion of a rotor which tends to maintain parallel the skewed axis of vibration and rotational axis, influences on the speed, sometimes doubling its number. For analysis of the general dynamic model has been built based on a model with a single non-central disk with necessary approximations for two types of support – rigid and elastic bearings and as well as for rigid and elastic foundation. Based on adopted dynamic model the mathematical model was built. The model includes the dynamic analysis of the transient process involving mechanical, thermal and electromagnetic processes. Such processes occur at rotating machines with instantaneous changes in machine conditions as speed, load, usually during start-up or shutdown. 937