Diagnosability of Slowly Changing Fault of Hybrid System

The premise of model-based diagnosis is that the system for diagnosing is diagnosable. Previous methods to diagnose fault are mainly based on the assumption of abrupt change, and under this kind of assumption, unpredictable fault can be caused by those possible slowly changing fault or that the system cannot be diagnosed. Diagnosability of slowly changing fault is discussed in this essay, and the determination method of diagnosability of slowly changing fault is put forward in the framework of hybrid input-output automata. By introducing guard event system of slowly changing fault, the diagnosing method of slowly changing fault is obtained and the feasibility of the mode is proved.