New fault-tolerant induction motor control architecture for current sensor fault in electric vehicle

This paper is dedicated to the synthesis of an active fault-tolerant control (FTC) scheme for an induction motor (IM) drives in automotive applications in the presence of three current sensors predisposed to arbitrary faults. A differential algebraic approach is applied to perform the fault detection and isolation (FDI) task and to estimate the current residuals dynamics in the stationary reference frame. The resulting residuals are sent next to a decision making unit which detects the fault occurrence and identifies the faulty sensor based on a threshold based scheme. An online reconfiguration is then performed by calculating the appropriate current signal that will be used by a RISE-Backstepping controller to make the drive fault tolerant and to keep system performances unchanged even under faulty current sensor. It is shown that the proposed sensor FTC architecture allows detecting different kind of current sensor faults depending only on the input-output measurements and their derivatives with just a simple 1-D fault estimator model. Besides, it is valid and applicable for any IM drive control schemes and is able to reestablish from sensor fault condition. Furthermore, the used residual threshold is well defined and is suitable for the whole operating range. The robustness of the generated residuals to load torque disturbances is also demonstrated. Simulation results are provided to illustrate the effectiveness of the proposed FTC scheme.