Research On Equivalent Power Model Of Uhvdc Converter Station Under Large Disturbances

Compared with high voltage direct current (HVDC) transmission, ultra high voltage direct current (UHVDC) transmission has more advantages obviously, which can perfectly satisfy the power requirements in China. In order to simulate and analyze the electromechanical process of large power grid. it is necessary to establish an accurate power model of UHVDC converter station. Firstly, according to the measured data of Yin-Dong DC commutation failure in 2011 and "6.14" Tian-Zhong DC blocking and simulation data based on PSCAD, the operation mechanism of UHVDC system and the output characteristics of active power and reactive power of UHVDC converter station under large disturbance is analyzed in detail. Then, based on event-driven ideas, an equivalent power model is proposed. Finally, based on PSASP software, the accuracy of the new model is validated by comparing with the measured result and the results of quasi-steady state model, the presented model in this paper is more accurate in describing the power characteristic of UHVDC converter under large disturbances.