Analysis and treatment of sudden increase in the swing degree of turbine guide bearing of a hydropower unit

The variation of the swing value of the guide bearing of the hydropower unit is directly related to the safe and stable operation of the unit. This paper analyzes the cause of the abnormal situation that the swing value of the water-turbine guide bearings of the unit 6 of a hydropower station suddenly increases by three times. After analysis, the main reason for the increase of the water-turbine guide swing is due to the design defects of the water-turbine guide assembly of the unit, and the lack of a restriction structure for the expansion of the clearance, which causes the clearance increases sharply after long-term operation. At the same time, the unbalance of mass and electromagnetic force of the generator set is the secondary reason for the sudden increase of the swing value of the water-turbine guide bearings. The methods of optimizing the assembly structure of the water-turbine guide bearing and carrying out the dynamic balance test counterweight were taken to deal with the site. After treatment, the swing value of the guide bearing of the unit returns to normal.