Power flow control in multi-terminal electrical complexes, taking into account the effect of dc line resistance

Losses due to voltage drop in the DC line have a significant impact on the accurate control of power flow in multi-terminal VSC-HVDCs using DC voltage droop control. When DC voltage droop controls are used in multi-terminal VSC-HVDC, due to unequal DC bus voltages, voltage drops in the DC link cause large power flow variations in the DC grid. Power losses in the DC link and converter power losses also cause deviations in the power flow in the DC network. To accurately control the power flow in a DC network, it is necessary to eliminate the power deviations that occur due to each of these factors. Modeling a five-terminal VSC-HVDC system in Matlab/Simulink shows how to achieve precise power flow control in a multi-terminal VSC-HVDC, taking into account the reduction of DC voltage and power losses in the DC line (accounting for converter power losses is beyond the scope of this article).