Fault severity estimation in a vehicle cooling system

On-time water pump malfunction, thermostat sticking, fan defect, and radiator clogging severity estimation in a vehicle cooling system prevents system breakdown and saves repair costs and service time. In this respect, to minimize the required number of engine variable measurements, the engine body temperature, T-b is introduced as a single driving force of the thermal system and a modified adaptive second order sliding mode (SOSM) fault observer is utilized to estimate the (single case) faults despite the system nonlinear uncertainty. The faults are applied and the estimates are obtained within the defined temperature ranges. The results of extensive simulations indicate that the algorithm works well in assessing the occurred damages to the uncertain system.