Future offshore wind farms are expected to be placed further away from shore, which will give rise to more employment of HVDC transmission. However, HVDC transmission requires a bulky and expensive power conversion substation at offshore as well as a dedicated supporting platform. Potential elimination of the platform and centralized conversion station leads to great cost savings. Recent proposals of pure dc series offshore wind farms are due to this motivation. The series connection of the wind turbines enables to establish the HVDC transmission voltage level with no extra voltage step-up substation, which makes it attractive for distant large wind farm. However, as series connected in one cluster, wind turbines are not possible to operate independently. Severe wind variation imposes overvoltage on the wind turbines and may provoke a cascade of failures of other series connected units. This paper describes the operating behaviour of dc series offshore wind farm as well as correspondent control strategies in both sound and fault conditions. A simulation of the dc series wind farm is carried out and validates the feasibility of the proposed control strategy. DC series offshore wind farms with proposed control imply competitive economic advantages of future integration of remote energy generation.