Vibration Analysis of Rotating System in a Turbine and Generator Set: Comparison of Shrunk-fit Disc Rotor and Welded Drum Rotor

터빈발전기의 축계 진동 해석: 열박음형과 용접형 로터의 진동 특성 비교

Excessive vibration magnitude results in serious damage and economic losses in the turbine and generator system. Therefore, it is of importance to evaluate the accurate dynamic characteristics of the system in advance. In this paper, rotordynamic characteristics of both the shrunk-fit disc and welded drum rotors have been investigated to ensure an excellent running behavior of the system in which low-pressure(LP) turbines of a nuclear power plant were retrofitted to improve thermal efficiency and reliability. Analysis shows that the welded drum rotor has good torsional characteristics rather than the shrunk-fit disc rotor. In addition, verification testing of field test was performed to confirm the retrofit. Test results are good agreement with analysis ones.