Younes Azzoug

This paper presents a robust and adaptive control strategy for wound rotor synchronous machines with anodized aluminum tape coils, designed to operate reliably at temperatures around 300°C. At such high temperatures, significant changes occur in key motor parameters, including resistance, inductance, and flux linkage. These variations adversely affect the accuracy and stability of speed and current control, making traditional control methods insufficient. To address the challenge, the proposed approach combines cascaded control loops with advanced parameter estimation techniques. Leveraging adaptive algorithms, the system dynamically and continuously estimates and compensates the variations in resistance, inductance, and rotor flux, thereby ensuring accurate control of stator currents and rotor speed. On top of that, the strategy integrates a disturbance observer to detect external perturbations and adjust control actions in real time, improving the overall robustness of the machine under varying operating conditions. Simulation and experimental results confirm the effectiveness of the proposed adaptive robust control strategy, demonstrating improved performance and stability of the wound rotor synchronous machine even under extreme thermal operating conditions.

This paper presents the experimental validation of a Fault-Tolerant Control (FTC) system for Permanent Magnet Synchronous Motor (PMSM) drives, specifically focusing on current sensors. The FTC system is designed to detect and diagnose both single and multiple faults in the current sensors and to reconfigure the control loop to ensure uninterrupted operation in the presence of such faults. Several crucial aspects are addressed in the proposed approach, including fault detection, isolation of faulty sensors, and reconfiguration of the control system through accurate current estimation. To achieve this, a novel adaptation of the Luenberger observer is proposed and employed for estimating the stator currents. The effectiveness of the fault-tolerant control strategy is demonstrated through experimental tests conducted on a 7.2 kW PMSM utilizing a field-oriented vectorial strategy implemented in a dSpace 1104 platform.

This paper introduces a simple and low-cost direct vector control method without current sensors for Permanent Magnet Synchronous Motor (PMSM) drives, using only a single estimator and the measured dc-link voltage, as well as the measured rotor speed for currents reconstruction. The proposed method is based on a new modification of the adaptive state observer to estimate the line currents. A theoretical concept is developed, the modified adaptive state observer is presented. Simulations tests are performed to prove the ability of the proposed scheme to reconstruct stator currents and reproduce the performances of a basic and traditional vector control PMSM drive.

Finite-State Model Predictive Control methods (FSMPC) have been presented recently in the field of electrical drive and power electronics as an alternative to the conventional strategies. This paper presents a comparative evaluation between Direct Torque Control (DTC) and two finite-state model predictive control strategies applied to induction motor drive. Both DTC and MPC are nonlinear control techniques which dispense with the use of modulation unit (i.e. pulse width modulator (PWM) or space vector modulator (SVM)). DTC can provide good decoupled flux and torque control using pair of hysteresis comparators and lookup switching table for voltage vectors selection. In contrast with the model predictive control which includes the inverter model in control design. The optimal selection of inverter switching states minimizes the error between references and the predicted values of control variables by the optimization of a cost function. The effectiveness of applied algorithms is investigated by an experimental implementation using real-time interface (RTI) based on dSpace 1104.

this paper deals with a speed sensor fault tolerant control (FTC) scheme for induction motor (IM) drive based on direct torque control (DTC) and adaptive stator flux observer (ASFO). Many important points are treated in the proposed algorithm, which are the detection of the sensor failure, isolation of the faulty sensor and the reconfiguration of the control system by proper estimation. An adaptive stator flux observer is used instead of classical flux and torque estimator to perform the stator flux components, electromagnetic torque, flux magnitude, rotor position and the estimated rotor speed. Furthermore, a fault detection and isolation (FDI) logic circuitry is used to detect speed sensor fault and isolate it and simultaneously generate a logic impulse to switch to the sensorless mode. The proposed algorithm is simulated in MATLAB/Simulink.