Analysis of spatial characteristics of HVDC commutation failure in complex power grid

Set up a model of typical minimum ac/dc system. From the electrical distance and the phase difference of steady state between fault point and converter bus to research the spatial characteristics of HVDC commutation failure. Simulation results show that under the condition of invariable system support strength, the electrical distance between fault point and the converter bus is the main factor affecting the spatial characteristics of HVDC commutation failure. The closer the electrical distance is, the more likely to cause a dc commutation failure. The influence of power flow to HVDC commutation failure is mainly embodied in the phase difference of steady state between the fault point and the converter bus. The lager the phase of the fault point is, relative to the phase of the dc converter bus, the easier the HVDC occurs commutation failure.