Condition Monitoring framework for Converter Transformers used in Marine Electric Propulsion

Electrical and magnetic domain parameters for online condition monitoring of converter transformers used in marine power system is explored, where the traditional DGA and PD techniques are not much applicable. Current signal and leakage flux from transformer core and winding are studied, with an emulated inter-turn fault in a 10 kVA lab-scale converter transformer. It is expected that the presence of valve winding in converter transformer will pose a challenge, for condition monitoring as it has inherent harmonics. There is a need for an online monitoring technique which is simple, cost effective and rugged to diagnose the fault and raise an alarm on-board ship, as it may lack the right maintenance technician or a replacement transformer during the voyage. Method of emulating the inter-turn fault in transformer, experimental studies and the frequency domain results from electrical and magnetic sensors for condition monitoring are discussed.