Abstract: Modeling of the DC grid is the prerequisite for analyzing the resonant characters and stability issues. It is significant to improve the operating characteristics of DC grid by designing a well-performed damping controller. Firstly, a Thévenin’s model of the converter was derived from the averaged converter model using power-balancing principle. Secondly, the small signal model（SSM） of DC grid was established considering the network frame, and then the resonant characteristics were studied. Thirdly, a power damping control strategy was proposed by feeding back the DC current outputted from the converter. The realization form of damping controller was analyzed and its parameters were designed. Finally, electromagnetic and RT-LAB real-time simulation models were constructed. Both results validate that the proposed damping control strategy can suppress the resonant current in DC grid and improve the operating stability of the system.