Transmission Contingency Screening Considering Impacts of Distribution Grids

As traditional transmission contingency screening (TCS) methods neglect impacts of distribution grids, the contingency selection result may not be always satisfactory, especially when distribution networks are more frequently looped in a smart grid. Two new contingency screening methods considering impacts of distribution grids are proposed in this letter. The first one is based on global power flow, and the second only utilizes distribution network equivalencing. Numerical tests show both new methods can give more reliable results than TCS.