Research on the influence of fault current limiters on commutation failure and transient stability in AC/DC power system

In this paper, the method of installing fault current limiters (FCLs) near DC converter station is proposed, which is aimed at the commutation failure caused by short circuit fault of the DC inverter side in AC/DC power system. Influence mechanism of FCLs on suppressing commutation failure is analyzed. What's more, effects of FCLs in different locations on commutation failure are compared. In addition, theoretical analysis of transient stability on multiple high voltage direct current (HVDC) commutation failure system with FCLs is discussed using the extended equal area criterion (EEAC) theory. Finally, simulation is carried out based on an actual power grid. Theoretical and simulation results show that, the action of FCLs can not only limit the short-circuit current, but also effectively suppress commutation failure and alleviate the power imbalance and the transferred system flow caused by the concurrent commutation failures, which can significantly decrease the power impact of the regional section and improve the transient stability of the system.