Emergency Control for Fast Frequency Response of System Connected to Multiple VSC-HVDC Based on Wide-Area Measurement System

Aiming at system connected to other systems through multiple VSC-HVDC, an improved steady-state frequency prediction method based on Wide-Area Measurement System is presented. This method takes into account the power loss, the static characteristics of load, the steady-state model of VSC and the generator governor with mechanical damping, which can predict the steady-state frequency after disturbance quickly and accurately. Based on this online frequency prediction method, an emergency control strategy for VSC-HVDC is designed, which can recover the frequency of disturbed system to desired value while minimize the frequency variation of systems connected to the other side of multiple VSC-HVDC. Using the Differential Evolution algorithm, the optimal emergency power support for multiple VSC-HVDC can be rapidly solved. Finally, the improved IEEE 39 bus system was simulated in PSS/E and analyzed to verify the correctness and effectiveness of the steady-state frequency prediction method and emergency frequency control strategy.