A multi-point DC Voltage Control Strategy of VSCMTDC Transmission System for Integrating Large Scale Offshore Wind Power

This paper proposes a multi-point DC voltage control strategy of voltage source converter based multi-terminal DC (VSC-MTDC) transmission system for integrating large-scale offshore wind power. Taking a typical four-terminal DC transmission system for example, DC power flow distribution is analyzed, DC flow calculation model is derived and active power control of auxiliary converter station with DC voltage-active power characteristic is proposed. Finally, simulations in PSCAD/EMTDC are conducted to verify the validity of multi-point DC voltage control method under various operating state and MATLAB programming are undertaken to verify the accuracy of DC power flow model. Results show that this method can guarantee the active power allocation of VSC-MTDC transmission system and good control effects are obtained.