Fault diagnosis system, fault diagnosis equipment and fault diagnosis method

摘要

PPROBLEM TO BE SOLVED: To provide a fault diagnosis system, or the like, capable of specifying a fault occurrence condition, even when the fault resulting from a cause that is not assumed, in advance, occurs. PSOLUTION: This fault diagnosis device 5 calculates a difference signal set (S105). The fault diagnosis device 5 does not determine, when there is at least one piece of time series data during normal time, when a signal value with a different value becomes an empty seta as a result of comparison, that the time series data during an abnormal time to be compared does not include fault occurrence condition, and excludes the set from subsequent processing objects. The fault diagnosis device 5 formulates it into a form of the maximum satisfiability problem (S106). The fault diagnosis device 5 calculates a fault occurrence condition (S107); and the fault diagnosis device 5 calculates the value of a signal or the combination of signal values to be the fault occurrence condition, by repeating processing which calculates the solution of the maximum satisfiability problem formulated in S106, sequentially adds a logical expression negating the calculated solution as a constraint condition and recalculates the solution, until there is no solution. PCOPYRIGHT: (C)2010,JPO&INPIT