Compatibility Study of 16.5 MW TG Foundation for accommodating new 22 MW TG

A detailed compatibility assessment was carried out for an existing 16.5 MW Turbo Generator (TG) foundation to evaluate its suitability for accommodating a new 22 MW unit. The foundation, of an unconventional braced configuration, underwent extensive non-destructive testing (NDT) and dynamic analysis. Results indicated: Actual concrete strength around M20, with a corresponding elastic modulus reduction from 3.0 × 10⁴ MPa to 2.0 × 10⁴ MPa. Structural stresses under the most critical load case remained within permissible limits, ensuring adequate static safety margin (~40%). The vertical natural frequency (24.7 Hz) was found close to the operating speed (25 Hz), highlighting a need for dynamic modification. Recommended modifications included removal of bracings and intermediate beams, column strengthening and structural isolation from adjoining elements. The study concluded that, with these dynamic improvements and subsequent validation through on-site vibration testing, the existing foundation can safely support the upgraded TG system.

COMPATIBILITY AND CAPACITY UPGRADATION