Offshore Wind Farms Integration Using HVDC Transmission System

Abstract

Human efforts of harnessing wind energy had started in ancient times, when they used to sail ships and boats. Wind has gained popularity mainly in recent years, as it is renewable, eco-friendly, non-polluting and non-depleting source of energy. Wind parks are planned to be placed into sea far away from the mainland. The wind speed does not remain constant and thus require a generation which can extract maximum power from the wind. Doubly fed Induction Generator (DFIG) is a solution for such large wind turbines connected with offshore wind farms. The stator of the generator is directly connected to the grid while the rotor is connected through back-to back converter. With this the maximum power from the DFIG can be harnessed. The modeling and dynamic performance of the wind driven DFIG system is studied for two cases: DFIG Connected with AC system and DFIG connected with HVDC system. The system model is realized in simulink environment. The performance of system is investigated for the change in wind speed, change in grid voltage, change in load and change in length of the transmission line for AC and HVDC systems.