Research On Generating Set Vibration And Coupled That And Hydropower House Vibration In Hydropower Station

The capacity and dimension of water turbinegenerating set has been sharply increasing with the rapid development of hydropower construction. At the same time, rotational speed has been increasing correspondingly. As a result, the vibration problem of water turbinegenerating set and the vibration of hydropower station's house are standing out gradually, which becomes an important issue to be studied. Obvious vibration has been happening in some hydropower stations with large capacity and high water head, which affects the normal work of water turbinegenerating sets. So it is an urgent work to study the vibration sources and vibration problems.nonlinear dynamic characterastics of labyrinth seal-rotating wheel system in hydraulic turbines has been analyzed in this thesis. Dynamic characteristics of journal bearing and thrust bearing have also been studied. The action and transmit mode of vibration loads has been discussed. A vibration mechanical model of hydropower house, water turbinegenerating set and transmit force system has been made to research their dynamic characteristics, which would provide theoretical and technical instruction for optimizing the structure and controlling the vibration of hydropower house and water turbinegenerating set.Chapter one simply introduces the vibration of hydropower house and water turbinegenerating set and its studying situation. This part also simply summarizes the dynamic characteristics of supporting structure, the vibration characteristics of seal-rotating wheel system in hydraulic turbines and the action and transmit mode of vibration loads.In chapter two, the lateral vibration mechanical model of shaft system is created based on the finite element method (FEM), and the critical rotation speed of transverse revolving vibration of shaft system is calculated. Sensitivity analysis of critical rotate speed and dynamic response is performed by changing different parameters of the system. According to the results, the thesis gives suggestions about how to control the vibration sources and how to optimized the structure of shaft system in water turbinegenerating set.In chapter three, the couple behavior between the thrust bearing and journal bearing of water turbinegenerating set is investigated. The finite element method is used to analysis the lateral vibration mechanical model of shaft system, the natural frequency of transverse revolving vibration of shaft system is calculated according to complex model method. Through analysis the influence of couple behavior between thrust bearing and journal bearing to investigate stability of shaft system in water turbinegenerating set.