Aiming at the DC voltage oscillation induced by the poor interaction between the power electronic device and the DC network in the multi-terminal DC power distribution system

we proposed an improved active damping control strategy. Taking the master-slave system as a research object

we analyzed the adverse interaction mechanism between the system voltage control core device

constant voltage VSC

and DC system resonant mode

and revealed the system voltage control loop which is caused by the change in the VSC steady-state power point has a degrading effect on this bad interaction. Based on the results

we proposed an improved active damping controller. The controller can independently adjust the damping characteristics of the frequency bands in each zone

respectively

and causes the poor resonance interaction behavior of the source network and the steady state power variation of the VSC. The deterioration effect is suppressed

and the stability of the system is improved. Finally

the effectiveness of the proposed active damping control strategy is verified by electromagnetic transient simulation. The results show that the active damping controller proposed in this paper can provide higher additional damping and further expand the stability domain of the system compared to the traditional active damping controller.