Ground currents at dockside trials of ship electric plant
Object and purpose of research. Estimation of ground currents at dockside trials of ship electric plant using loadbank. Methods. Ground currents are estimated at different neutral point connection (from insulated to dead-grounded neutral) taking into account shore cable line. Main results. Relationships to define the ground current at different neutral point connections are derived. The loadbank and its regulated element are described. Options are suggested for reducing the size of loadbanks without compromising the cooling efficiency, while retaining the rated power factor. Conclusion. Current in neutral is generally a clear sign of reduced isolation resistance. In this case the neutral current is three times the zero-sequence current.