The invention discloses a
nuclear power unit autonomous operation decision method and device, and the method comprises the steps: collecting the
equipment state information and equipment performance information of a
nuclear power unit in real time through a PHM tool in the operation process of the unit, and if the
equipment state is changed or the equipment performance is reduced, determining that the
nuclear power unit is an autonomous operation decision; if so, analyzing a related accident sequence of the equipment by using a
simulation technology to determine a sequence result; according to the sequence consequence obtained by
simulation analysis, updating a PSA model of the nuclear
power unit to carry out
risk assessment, obtaining a risk value, and judging whether the risk value is in a risk yellow area; if so, establishing an alternative scheme set; analyzing the alternative scheme set by using a deterministic
theory analysis method to determine a first scheme set; according to the first scheme set, a probability
theory analysis method is used for analysis, and a second scheme set is formed; and for the second scheme set, based on the deterministic theory
safety index, the probability theory
safety index, the economic index and weighting, comprehensive
decision making is carried out, and an optimal scheme is obtained.