Research Article
Using Simplified Models to Assist Fault Detection and Diagnosis in Large Hydrogenerators
Table 7
Natural frequencies of 1st Backward Precession Mode (BPM), 2nd Forward Precession Mode (FPM), 3rd BPM, and 4th FPM, with generator excited and unexcited.
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The symbol “”indicates that the shaft position is different. In the clearance condition A the pad clearances are in the nominal values (200 µm) and the shaft is centered at coordinates (0,0). In clearance condition A* the pad clearances are once more in the nominal values but the shaft has an eccentricity of 67 µm. |