Optimal Robust Sensorless Control of an Induction Motor Supplied via a Long Cable

In medium-voltage (MV) induction motor (IM) drives where the motor is connected to the inverter via a long feeder cable-such as in submersible extraction pumps-sensorless control presents significant challenges. This paper proposes a novel sensorless control strategy based on an H2 -linear matrix inequality (LMI) optimal control scheme, designed to enhance robustness against cable parameter uncertainties. An extended Kalman filter (EKF) is integrated to estimate the system states, avoiding the presence of any sensor close to the motor. Simulation results, considering an IM fed by an H-bridge MV multilevel converter via a 20 km cable, demonstrate the effectiveness of the proposed strategy in achieving fast response and robustness to parameter variations.