Flow Restrictions in Water-Cooled Generator Stator Coils:Proevention,Diagnosis and Removal

摘要

Flow restrictions in the stator bar cooling channels are commonly caused by copper oxide deposits.The paper discusses the mechanisms of such flow restrictions:formation,release,migration and transport of copper oxides.These parameters canbe controlled by water chemistry.Of the 1,600 water-colled stators world-wide(excluding Russia,China and Japan),about half operate under high-oxygen chemistry,the other half under low-oxygen conditions.Alkalien treatment and "cationic purificaiton"are promising options.