XIN Yechun, YI Binxiang, WANG Tuo
Abstract (
)
Knowledge map
Save
There are differences in the critical extinction angle characteristics of high-voltage direct current transmission systems under different operating conditions. A small angle can easily cause commutation failure, while a large angle is not conducive to system economy and safety. In order to reduce the impact of the dynamic characteristics of the critical extinction angle on commutation failure, firstly, the effects of forward current, current zero crossing change rate, and junction temperature on the critical extinction angle were analyzed, and an approximate calculation model for the critical extinction angle was established to characterize the recovery and blocking ability of thyristors. Then, based on the approximate calculation model of the critical extinction angle, a commutation failure suppression strategy for dynamic compensation of current deviation angle is proposed by analyzing the stage of the effect of the critical extinction angle of the converter on commutation failure in the control system. Finally, simulation experiments were conducted based on the CICRE high-voltage direct current testing model under different operating conditions, and the results showed that this strategy improved the suppression effect of commutation failure under different operating conditions, effectively avoiding the occurrence of subsequent commutation failures.