Comparison study on restoration strategies of chongqing power grid

The efficient restoration after large-scale electric interruption is an important subject for ensuring the secure operation of power systems. This paper applies the concept of "generic restoration milestones (GRMs)" to develop two different restoration strategies of Chongqing power system. One adopts build-outward approach that utilizes internal hydropower as black-start units. Another adopts build-inward approach that utilizes external power source as black-start units. Comparison study results show that the build-inward strategy uses less time than the build-outward strategy, thereby promotes the process of restoration. It can assist system operators in selecting an optimal restoration plan.