Dual End Grid Control Strategy for Offshore Wind Power Grid-Connected MMC-HVDC System Considering DC Line Loss

With the continuous expansion of the scale of offshore wind power, its grid-connected access puts forward higher requirements for the stability and reliability of the power grid. High voltage direct current (HVDC) systems, primarily modular multilevel converter (MMC) technology, are ideal for offshore wind power grid integration due to their high efficiency, reliability and flexibility. However, the inherent parasitic losses in long-distance DC transmission lines substantially degrade system operational efficiency. To address this challenge, this study develops a bipolar control architecture for offshore wind-integrated MMC-HVDC systems, explicitly incorporating line loss dynamics into the control loop design. This strategy significantly improves the power transmission efficiency by optimizing the power control at the wind farm end and the land access end, combined with the loss compensation mechanism of the DC line. The proposed control strategy can improve the power transmission efficiency of the system by 4<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">%</sup> to 6% compared to the legacy control strategy, with concurrent preservation of system dynamic stability and functional reliability.