In recent ten years scholars around the world have widely studied the cascading failure and blackout applying the self-organized criticality theory

but DC transmission and complete system dynamics are not considered in most of the studies. Different DC operation modes

DC control parameters

AC/DC interconnection modes

and AC/DC capacity distributions will affect the self-organized criticalty of the AC/DC interconnected system. A dynamic cascading failure model considering probability characteristics of emergency control & protection device and DC system is proposed

with which dynamic simulation of the 2010 East China power grid is performed. Under conditions of different DC operation modes

DC control parameters

AC/DC interconnection modes

and AC/DC capacity distributions

the outage power—outage probability power law curves of the system are calculated

the impact of the DC transmission on system self-organized criticality is analyzed. It can be known from the results that in certain system

the probability of cascading failure and blackout can be decreased by selecting the suitable DC transmission mode.