Doosan is equipped with cutting-edge technologies and extensive in-house expertise in the design, manufacturing, and servicing of generators. We offer a comprehensive lineup of generators, including air-, hydrogen-, and water-cooled models, and have supplied more than 230 units worldwide, covering both new installations and retrofit projects.

Leveraging our in-house capabilities in design, engineering, inspection & testing, diagnosis, and performance evaluation, we have successfully executed a broad range of generator repairs, rewinds, and upgrades.

Doosan provides assessment and Residual Life Assessment (RLA) services to evaluate generator condition and estimate remaining service life through its comprehensive generator diagnostic programs, which can be conducted during scheduled plant overhauls. Based on the diagnostic results, we recommend required repair and replacement items for the next overhaul, enabling customers to plan effective preventive maintenance strategies. In addition, our team of experts performs root cause analysis to identify and prevent generator-related incidents.

Stator Tests

• Insulation resistance & P.I. – Assess the condition of stator winding insulation
• Winding resistance – Verify whether stator winding phase resistance values are within permissible design limits
• High-potential (Hipot) test – Verify insulation integrity and dielectric strength
• Wedge tightness test – Inspect wedge assembly integrity
• Bump test – Identify resonance potential by measuring natural frequencies at stator winding end regions
• Water leak test – Detect leakage within the stator winding cooling water system
• Water flow line test – Identify internal clogging in the stator winding cooling circuits
• Dissipation factor (tan δ) test – Evaluate insulation drying condition, moisture absorption, aging, and void presence
• AC current test – Assess stator winding insulation condition under applied AC voltage
• Partial discharge test – Detect insulation deterioration through partial discharge activity
• Capacitance mapping test – Detect moisture ingress in stator winding insulation
• Core tightness test – Assess stator core lamination condition
• EL-CID test – Detect core insulation defects by identifying localized eddy currents

Rotor Tests

• Insulation resistance & P.I. – Assess the condition of rotor winding insulation
• Winding resistance – Verify whether rotor winding phase resistance values are within permissible design limits
• Pole balance and impedance check – Detect potential short circuits in rotor windings
• RSO test – Identify inter-turn short circuits in rotor windings using waveform comparison
• Voltage drop test – Evaluate rotor winding insulation condition and detect short circuits
• High-potential (Hipot) test – Verify insulation integrity and dielectric strength
• Non-destructive examination (NDE) of retaining rings and associated rotor components