Assessment method for identification of electrical connectivity and thermal stability of power grid

Primary equipment failure in substation has a significant impact on the reliability of the power supply, and even threatens the thermal stability of power grid. This study presents a method identification of electrical connectivity and thermal stability assessment of power grid after primary equipment failure. The identification method of electrical connectivity based on incidence matrix provides a way to determine load curtailment after equipment failure. Subsequently, the inject power of substation bus in power grid is modified by load curtailment. Moreover, based on the DC power flow model, the active power flow distribution of power grid is calculated, which is used to evaluate whether the active power of lines exceeds limit. Compared to the traditional N − 1 assessment method, this method not only has the advantages of fast calculation and strong pertinence but also of convenience for the field application.