With the official commissioning of the Nanhai Fenjin FPSO， the stable operation of the power system has become increasingly crucial. As a special transient phenomenon during the no-load closing of transformers or the restoration after faults， the magnetizing inrush current may lead to a series of adverse consequences such as equipment damage， incorrect operation of devices， and power system failures， which have added numerous risks to the stable operation of the Nanhai Fenjin FPSO's power system. Based on the power system of the Nanhai Fenjin FPSO as the background， this paper conducts an in-depth analysis of the causes and hazards of the magnetizing inrush current， and focuses on discussing the application of the magnetizing inrush current suppressor in the Nanhai Fenjin FPSO， including its working principle， selection considerations， installation， debugging， and actual effect evaluation， aiming to provide useful references and examples for similar projects.