  With the large-scale hybrid AC-DC grids coming into being, electromagnetic
transient (EMT) simulation is required to accurately describe the dynamics of
systems. However, the EMT steady-state initialization for hybrid AC-DC system
is difficult and time-consuming when the system scale is huge. In order to
provide a stable snapshot for EMT simulation with nonlinear components and
black-box components, this paper proposes a general initialization scheme for
EMT simulation (EMT-GIS) which can be implemented in the electromagnetic
transient program (EMTP)-type simulators. First, an integrated power flow (IPF)
algorithm is introduced to provide the steady-state results. Then, an
initialized snapshot calculation-and-splicing mechanism is designed for
EMT-GIS. The proposed EMT-GIS is tested using a hybrid AC-DC system in China on
the CloudPSS simulation platform. Test results verify the effectiveness of the
proposed EMT-GIS.
