The cathodic protection system of the FPSO project is mainly adopted in the following two ways:

Impressed current cathodic protection.

·‌ Principle ‌ : Negative potential is applied to the hull through external DC power supply to form cathode polarization and inhibit metal corrosion ‌15.

·‌ advantages ‌ : large current output, wide protection range, long service life, suitable for long-term deep-sea operation of FPSO ‌.

·‌ Core components ‌ : auxiliary anode (need erosion resistance, corrosion resistance), reference electrode (monitoring potential), potentiostat (regulating current) ‌..

‌ sacrificial anode cathode protection .

·‌ principle ‌ : by connecting more negative potential metal (such as zinc, aluminum alloy) as anode, priority corrosion to protect the hull ‌.

·‌ Application scenario ‌ : suitable for small devices or partial protection with low maintenance cost but periodical replacement of the anode ‌.