Effective short circuit ratio including impact of STATCOM

The paper simplifies the model of STATCOM, then evaluates its impact of access to power grid based on network equation, in this way, proposes a new kind of index named broad effective short circuit ratio (BESCR) based on effective short circuit ratio (ESCR). This index can be used to evaluate the voltage supporting capability of receiving system of single-infeed HVDC and multi-infeed HVDC under weak coupling with STATCOM. Then, the paper uses the maximum power curve (MPC) to validate the availability of the index, gives the relationship between the index and the maximum available power (MAP), and also puts out the index's threshold for system strength discrimination according to simulation results. The index has certain guidance meaning for location selection of the STATCOM in power grid.