Risk assessment of cascading failures in power grid based on fuzzy comprehensive evaluation

The cascading failure is an accident with a low probability but very serious consequences, leading to blackouts or even the whole system crashes. From the perspective of preventing cascading failures, this paper considers the probability and consequences of accidents, using the hidden fault probability and the line fault probability as probability indexes, taking the indexes of lost load, low voltage and overload that reflect static security of system grid as severity indexes. Apply fuzzy comprehensive evaluation to grade the indexes, and determine the level of risk based on the maximum principle membership. Finally, take the IEEE 39-bus system as a numerical example, verifying the rationality and validity of the algorithm.