I. Introduction
Smart grid control system is the basis for ensuring the observability and controllability of the power grid [1]. While smart grid control system greatly enhance and optimize the efficiency of the power grid operation, they also bring some new risks to the power grid [2]. Therefore, it is critical for the power grid operators to measure and monitor the vulnerability of smart grid control system in real-time, which is helpful to take the secure and stable operation of smart grids and further prevent severe outage accidents.