This paper proposes a new emergency dc power support (EDCPS) strategy to improve the rotor stability of the power system. The traditional EDCPS in high-voltage dc (HVDC) transmission system is a power modulation control functions based on predetermined criteria of monitored AC system parameters and activated from power system stability control. The control quantities are composed of a few preset fixed gears and may not adapt to the ever-changing state of the grid, which may cause insufficient control and lead to external generator tripping to stabilize the system. Hence this paper proposes a new response-based EDCPS strategy, which plans a δ-ω trajectory and real-time calculate the control quantity. Simulations are run in a single-machine infinity bus (SMIB) system and a modified New England 39-bus system by DIgSILENT/PowerFactory to validate the effectiveness of the proposed scheme.

HVDC,EDCSP,δ-ω Trajectory,Rotor-Angle Stability