Determination of the Degradation Pattern of Pump Using Two-Phase Diagnostic Bond Graph

A bond graph-based approach has been applied for failure prognosis in the hydraulic circuit. The degradation function of a fault in the system is determined using a two-phase diagnostic bond graph model (DBG). By intentionally imparting a time-varying fault in the pump displacement, the capability of the DBG model is exhibited. The analytical redundancy relations (ARRs) evaluated from the first DBG helps to discern the manifestation of fault. Making use of ARRs of the first phase, the second DBG delivers the degradation pattern of the fault enabling the determination of remaining useful life (RUL) of the system.