In multi-terminal DC distribution systems

the system damping is reduced by the constant power characteristics of the load converters with constant power control

which can easily cause DC voltage and current oscillations

leading to system instability. Therefore

a phase compensation control strategy based on DC voltage feedforward is proposed. Firstly

the DC side impedance model of the load converter is established

and is reduced to a first-order impedance model based on the continuous fraction theory. Secondly

based on the first-order impedance model

the main factors affecting the negative damping characteristics of the load converter are analyzed

and a phase compensation control strategy based on DC voltage feedforward is proposed. The strategy can correct the load converter impedance to positive damping characteristic across the entire frequency range

thereby improving the stability of the DC distribution system. Finally

taking a three-terminal DC distribution system as an example

the effectiveness of the proposed control strategy is verified through Simulink simulation and hardware-in-the-loop experiment on StarSim.