Maintenance and repair of Hydro Power Plant
Tour inspection of generator
The main inspection items of the generator are as follows: first check whether the generator has abnormal sound, smell and abnormal vibration, whether the surface color and temperature of the generator have any problems. Reduce the rotor current appropriately and contact the maintenance personnel to deal with it; secondly, check whether the protection of each unit is put into normal operation, and the generator is not allowed to operate without main protection. If it is necessary for work, if it is withdrawn for a short time, please consult the chief engineer and obtain the provincial dispatch permission and control each The circuit and the excitation device should be put into normal operation. In addition, the daily early shift staff should measure the positive and negative pole voltage of the rotor of the running unit to ground, and check the rotor insulation. When the rotor insulation is good, the positive (negative) ground voltage is close to zero; when When the positive (negative) voltage to ground changes greatly, it means that the rotor insulation has dropped, and it should be checked and confirmed in time and notified. Finally, keep the generator clean, and inspect and maintain the brushes and slip rings in a timely manner.
Hydrogenerator repair
To eliminate the common faults of the hydraulic turbine, we must first clarify the parts with large wear and tear, and then check the parts with large wear through the daily replacement frequency to further find out the cause of the fault. For the fault of strong vibration of the unit, the cause is the cavitation of the turbine, the interlocking transmission part of the turbine and the generator is not concentric, the unit's anchor screw is loose, the draft tube is blocked and the bearing and bearing are damaged. At this time, it should be carefully checked, corrected and repaired. The maintenance method for generator noise and three-phase voltage imbalance failure is: dial the multimeter to the 1k resistance block, check the working condition of the silicon tube, find out if it is damaged, replace it, see if the excitation field varistor is open, and then check the additional winding . Disconnect the tail portion of the attached winding in the star connection, and use a multimeter to check whether each phase is open, whether the three phases are short-circuited and grounded. The most obvious thing is that the burnt place is the fault. Attention should also be paid to man-made mechanical damage during maintenance and assembly. It is suitable for various types of synchronous hydro-generator sets. Through these methods, we can eliminate common faults of the turbine in time and ensure the normal operation of the hydropower station.
