Current Sensor Fault Detection and Compensation Based on Single Modified Extended Luenberger Observer for Induction Motor Drive

Fault-Tolerant Control (FTC) strategies are increasingly being employed in modern drive systems due to high safety requirements. In the case of induction motor (IM) drive systems, knowledge of the stator currents is essential for implementing vector control structures. However, current sensors (CSs) may fail. This paper proposes a CS-FTC system which enables the detection and compensation of different CS failures. The modified Luenberger observer extended with simultaneous estimation of both winding resistances of the IM is used, which enables an accurate stator current reconstruction in the case of CS fault. In contrast to solutions known in the literature, the proposed approach utilizes a single observer, which allows for improved performance while simultaneously reducing computational requirements compared to dual observers and multi-observers.