On line monitoring of partial discharges on stator windings of large rotating machines in the petrochemical environment

The paper describes a joint collaboration program between a major large machine and a petrochemical manufacturer to investigate the effectiveness of time and frequency domain techniques for the online monitoring of the health of high-voltage machine stator insulation systems. Information is given on the factory and site testing carried out its well as on the analysis and discussion of the results. It is concluded that both techniques can be used in the petrochemical environment for general assessments, but the time domain technique is required if identification of specific locations of discharge sites is needed.