Simulation Study of Robust Backstepping Control for Five-Phase PMSM under Load Variations and Open Fault Phase

This study investigates the behavior of a Five-Phase Permanent Magnet Synchronous Motor (5P-PMSM) when an open-phase fault occurs. It applies a sensorless control approach that combines backstepping control with a Model Reference Adaptive System (MRAS) observer. Using measurable electrical quantities, including stator currents and voltages, the proposed method accurately estimates both rotor position and speed. The design of the backstepping controller follows a structured procedure to achieve global or semi-global stability, making it suitable for applications that demand reliable operation under changing conditions. Lyapunov theory is used to analyze and verify the stability of the combined observer and controller. The main objective of the research is to maintain motor performance and stable operation in the presence of an open-phase fault. Simulations conducted in MATLAB/Simulink compare normal motor performance with performance during the fault to evaluate the effectiveness of the control strategy. The findings show that the backstepping controller, supported by the MRAS observer, enhances fault tolerance and reduces the adverse effects. The simulation results confirm that the proposed approach sustains motor operation with minimal decline in performance, offering a dependable solution for industrial systems requiring resilience to faults.