Modeling and Control of an Offshore Wind Farm connected to Main Grid with High Voltage Direct Current Transmission

DOI: 10.26650/electrica.2018.73966 Offshore wind farms inherently need alternating current (AC) grid connection with undersea cables. However, this requires reactive power compensation, which is costly and not practical. Moreover, it threads the stability of the system. For these reasons, high voltage direct current (HVDC) transmission is a promising solution since no reactive power is needed. Furthermore, the DC power flow between offshore and onshore locations as well as the reactive power at either side can easily be controlled by voltage source converters (VSCs). In this paper, the modeling and control of an offshore wind farm connected to the mainland grid power with HVDC transmission is proposed. A control strategy is proposed to control active and reactive power at the offshore wind farm converter and DC voltage at the onshore converter. The overall system, including wind farm, offshore and onshore converters, HVDC transmission, and AC grid side, were tested and verified in a simulation environment. The designed control systems of the VSCs were tested by various case studies