Model-based electric traction drive resolver fault diagnosis for electrified vehicles

In electric and hybrid electric vehicles (EVs/HEVs) the electric traction drive plays an important role in producing driving torque. The motor torque request is calculated based on pedal positions from the driver and motor speed measurement from the position and speed sensor, typically the resolver. When there is a fault in the resolver that leads to inaccurate motor speed measurement, the vehicle supervisory controller may request undesired motor torque, which may lead to motor torque oscillations that could result in safety or degradation problems. This paper presents a model-based approach for diagnosing the resolver fault in the electrified vehicles, with focus on two typical types of faults, amplitude imbalance and quadrature imperfection. Before the diagnostic strategy is designed, resolver failure modes and fault propagation are analysed using a high-fidelity hybrid electric vehicle powertrain simulator. The proposed diagnostic strategy is implemented and validated through model-in-the-loop simulation, augmented by experimental data. Copyright © 2020 Inderscience Enterprises Ltd.