CHARGING OF AN ENERGY STORAGE SYSTEM OF A WIND TURBINE

A method of charging an energy storage system of a wind turbine is provided. The wind turbine includes a power generation system and a power delivery interface. The method includes obtaining a maximum power limit to which electrical power supplied to the external system via the power delivery interface is limited; monitoring an amount of electrical power provided from the power generation system to the power delivery interface or an amount of power generatable by the power generation system; and determining if a predefined condition is met. If the predefined condition is met, the wind turbine is operated in a charging mode in which electrical power generated in addition to a first amount of electrical power is supplied from the power generation system to the energy storage system to charge the energy storage system. The first amount corresponds to a power rating of the wind turbine.