This thesis deals with the repair and refurbishment of Generator 1 at the Ljubljana Combined Heat and Power Plant following the ingress of cooling water into the generator housing. During the overhaul, a damaged cooling tube was identified, which caused water and moisture to enter the generator and resulted in corrosion damage to several components. The thesis presents the complete repair process, from disassembly and inspection of the generator to cleaning, drying, refurbishment of damaged components, and final reassembly. Particular attention is given to the rotor, stator, bearings, coolers, and drainage system. Diagnostic and verification measurements used to assess the condition of the generator are also presented. Using Generator 3 as an example, the thesis includes measurements of insulation resistance, polarization index, dielectric dissipation factor, capacitive current, partial discharges, and the natural frequencies of the fan blades. The presented measurement results indicate that the inspected generator components were in satisfactory condition and highlight the importance of diagnostic measurements in verifying the quality of the maintenance and overhaul work performed.
|