Research about online security warning and risk assessment of power grid based on Energy Management System

In this paper, online security warning and risk assessment of power grid are proposed, based on date from Energy Management System(EMS), combined with information about real-time operation state, component status and external operating environment. It condenses the two factors, contingency likelihood and severity, that determine system reliability, into risk indices on different loads and operation modes, which provide precise evaluation of the power grid's security performance. Through these indices, we can know about the vulnerable area of the system and whether the normal operating mode or repair mode is over-limited or not, and provide decision -making support for dispatchers. Common cause outage and equipment-aging are considered in terms of the establishment of outage model. Multiple risk indices are defined in order to reflect the risk level of the power grid more comprehensively.