Offshore wind power flexible direct current system and control method thereof

The invention discloses an offshore wind power flexible direct current system and a control method thereof. The method comprises the following steps: acquiring a voltage per unit value and an active current value of a grid-connected point at a power grid side; when the voltage per unit value is greater than a first preset threshold value and the active current value is greater than a second preset threshold value, sending an additional control starting instruction to an inversion converter station of the flexible direct current power transmission system; monitoring a fault state of the flexible DC power transmission system, and judging whether a high-voltage fault is terminated or not according to the fault state; when the high-voltage fault is not terminated, starting an unloading circuit of the flexible direct-current power transmission system to control the output power of a hydrogen production system in the flexible direct-current power transmission system. According to the invention, during the high-volt