This paper proposes a power oscillation damping method to improve the damping characteristic of LCC-HVDC system. Firstly, the LCC-HVDC linearized model is established based on the motion equation concept. Then, the damping characteristic of LCC-HVDC system is analyzed. The analysis results show the impacts of DC current controller parameter and proposed power oscillation damping controller on the damping coefficients, which relate to the stability margin of LCC-HVDC system. Finally, the simulations based on PSCAD/EMTDC verify the accuracy of damping characteristic analysis of the LCC-HVDC system and the effectiveness of the proposed controller.

LCC-HVDC; motion equation; damping controller; damping characteristic analysis.