Failure detection diagnostics for thermofluid systems

This paper presents experimental results for an on-board microprocessor-based failure detection package designed to assist in the diagnosis of heat pump failures. A model-free limit and trend checking scheme, and a model-based innovations detection formulation operate in parallel to detect anomalous behavior. This dual approach permits the study of tradeoffs between failure detection performance and method complexity. A series of typical anomalies are experimentally simulated in a heat pump, and results are presented to demonstrate the performance of each detection strategy