LIFETIME EVALUATION OF HYDROPOWER PLANTS MECHANICAL EQUIPMENT FOR PREDICTIVE MAINTENANCE

Hydroelectric power plants (HPP) are one of the most used form of energy generation plants across the world and their development assures also the developing of other industries and economic sectors. The dams of a HPP are playing a major role in preventing floods and multiple use of the water (water supply, agriculture, etc). HPPs are playing a crucial role in the supply of grid system services while providing frequency and voltage balancing services. Their capabilities to adjust the generated power and operate at partial loads, to accumulate the hydraulic energy in reservoirs and to deliver energy with fast response time, recommends them to be actively involved in the grid services required to assure the continuity and safety in operation. However, not every HPP is most adequate to provide all type of energy balancing services due to their fundamental design. A derivation HPP designed with a higher value of the installed coefficient, will assure operation at peak region of the energy demand curve generating few hours per day and is mostly used to provide grid services rather than a run-of-river HPP. The main services provided are voltage and frequency regulation but also reactive power balancing which means that the generator unit is operating in compensatory regime. This paper presents the results obtained by researchers during a complete fatigue analysis study of the mechanical elements of a HPP equipped with a 55 MW Francis turbine. The analysis was done in order to determine the remaining lifetime of the main equipment, in order to develop the maintenance program if case.