In view of the insufficient stiffness of the upper bracket for a hydroelectric generator

the stiffness of the upper bracket in the horizontal direction is found to be significantly different from that in operation by analyzing the rotating frequency influence coefficient of the dynamic balance test. After comprehensive analysis of hydraulic factors

electrical factors

mechanical factors and dynamic balance tests

it is found that the over-standard vibration of the unit is due to insufficient rigidity of the upper bracket. The rigidity of the upper bracket is strengthened obviously after the treatment of the wrong installation way of the upper bracket Jack

and the problem of over-standard vibration pendulum of the unit is solved thoroughly.