Fault diagnosis and fault tolerant control for electrified vehicle torque security

Torque security is an important element for future automobile development such as for electric and and hybrid electric vehicles (EV/HEVs). For Drive-by-Wire systems that are commonly used in modern vehicles, pedal position signals are critical for ensuring correct calculation of torque request to the rest of the powertrain. This paper develops a model based fault diagnostic scheme for electrified vehicle powertrain torque security problems, with special focus on pedal position sensor faults. After the design of the diagnostic strategy, a fault tolerant control strategy is proposed to mitigate the effect of the faults. The torque security study is applied to a case study of a prototype vehicle developed by the OSU EcoCAR2 team. The diagnostic and fault tolerant control scheme are tested and validated through Model-in-the-Loop (MIL) and Hardware-in-the-Loop (HIL) simulations.