German turbine supplier Senvion has selected IMO’s latest T-Solid 4IPC roller-type pitch bearing for its 3.4 MW low-wind model 3.4M140 EBC, featuring a 140-meter rotor diameter and Eco Blade Control technology.
With either classic or load-based individual pitch control (IPC), and both large-scale onshore and offshore turbines, the company says individual blade pitch angles are continuously adjusted during each rotor revolution.
According to Senvion, this substantially reduces rotor blade and turbine loading, thus allowing lighter and less-expensive turbine designs and lower levelized cost of energy. However, without adequate counter measures, the resulting much-higher-pitch action frequency could substantially shorten pitch-bearing life.
IMO managing director, Werner Schröppel, said, “For such large-scale onshore turbines, T-Solid 4IPC combines two main benefits. First, it eliminates ring-separation and edge loading that is inherent to large-diameter conventional four-point bearings. Second, replacing balls by rollers ensures that extended pitch-bearing lifetime requirements for IPC operation will, indeed, be met.”