A MULTI-TERMINAL DC TRANSMISSION SYSTEM AND METHOD AND MEANS FOR CONTROL THEREOF

摘要

The invention relates to a method 30 for controlling power flow within a multi-terminal DC power transmission system 1 comprising two or more converter stations 10A, 10B, 10C, 10D, 10E. The method 30 comprises the steps of : controlling 31 the power flow to a steady state reference operating point 22A, 22B, 22C, 22D, 22E for operating points within a control dead band 21A, 21B, 21C, 21D, 21E defined for each respective converter station 10A, 10B, 10C, 10D, 10E, and controlling 32 the power flow by means of droop control in at least one of the converter stations 10A, 10B, 10C, 10D, 10E upon detection of exceeding of an end point of one or more of the control dead bands 21A, 21B, 21C, 21D, 21E. The invention also relates to a corresponding multi-terminal DC power transmission system 1.