A Novel DC Voltage Control Strategy for DC Distribution Based on Adaptive Droop Control

The stability of the DC voltage is one of the key technologies needed to be solved in the medium voltage DC distribution system (MVDCDS). Therefore, this paper proposes a novel master-slave control strategy based on the proposed adaptive droop control of the voltage source converter (VSC). According to this strategy, the master station operates in constant DC voltage mode as a reference of voltage and other slave stations adopt adaptive droop control with the dead band. When MVDCDS operates in steady-state, the slave stations output constant power to track the setting values, but if MVDCDS suffers from the lager disturbance, the slave stations can automatically switch to the adaptive droop control to rapidly regulate the DC voltage, so that the DC voltage does not overstep its limits. A two-terminal DC distribution system model is established by MATLAB/Simulink to verify the effectiveness of the proposed control strategy.