Monitoring the State of Shaft Voltage in Revitalized Generators at the Djerdap 1 HPP

Six hydropower units at the Đerdap 1 HPP have begun a new operating life after the revitalization. The revitalized units are equipped with modern devices for monitoring the operating condition in order to reduce the risk of outages, reduce maintenance costs and extend the service life of the equipment. In addition, the power plant staff periodically conducts additional measurements and analyses on individual assemblies and parts of the equipment in order to promptly detect deviations of certain parameters from the values that are common for the plant. One of the parameters that is periodically measured is the induced voltage on the shaft of the hydropower unit. This paper presents the results of shaft potential measurements in the previous period. The conclusions and measurements presented in this paper can help in understanding the occurrence of bearing currents and the necessary measures to reduce negative impacts on bearings as well as other irregularities in the operation of the hydropower unit.