Demonstration of fault ride through capability for closed bus operation on dynamic positioning vessels

To prove electrical systems on DP-2 and DP-3 class vessels can be safely operated in a closed bus configuration, recently published industry guidelines recommend fault ride through testing be conducted on DP-2 and DP-3 ships and platforms. To validate fault ride through capability, it must be demonstrated coordinated tripping will occur in the event of a main bus fault or a fault on a major feeder circuit and that generators and essential loads will “ride through” the fault without tripping. Demonstration of fault ride through capability for closed bus operation is not a simple task and the marine industry is still searching for standardized methods of testing industry owners and operators fully support. This paper will provide an overview of current available testing methods, discuss the rationale for conducting fault ride through testing, explore various types of testing methods to demonstrate fault ride through capability for closed bus operation, and recommend a list of testing practices to be considered.