Empirical Open‐Phase Fault Model for PC‐FPIM and Comparative Fault Tolerance Evaluation Against Star Configuration

ABSTRACT The objective of this research article is to probe the functioning of a five‐phase induction motor (FPIM) under the condition where one stator phase winding is disconnected. The stator winding can be connected in three possible ways, star, pentagon, and pentagram. The main aim is to develop a mathematical model for open‐phase fault in pentagon‐connected FPIM (PC‐FPIM). An empirical model is proposed and developed for evaluating the voltage across the open‐phase during fault. It also delves into the examination of performance parameters of the star‐connected FPIM (SC‐FPIM) and PC‐FPIM configurations during open‐phase fault. At full load, the torque ripple in the SC‐FPIM reaches 1.26 pu, whereas in the PC‐FPIM, it is limited to only 0.03 pu. This corresponds to an increase of about 126% in the star configuration, while it is only around 3% in the pentagon configuration. Furthermore, across all load conditions (20%–100%), the torque ripple in the pentagon configuration remains negligible, demonstrating its superior fault‐tolerant capability. The modeling of the fault is carried out using the back‐EMF approach, and this methodology is implemented in the MATLAB/Simulink environment for simulation. Additionally, the goal is to implement an appropriate fault‐tolerant control approach (FTCA) aimed at restoring the unbalance in the system caused after the occurrence of the fault. The reference currents required for the hysteresis controller are adjusted postfault by altering the components. This control is implemented in MATLAB/Simulink and is connected to hardware using dSPACE Real‐Time Interface. The simulation results accurately reflect the conditions associated with faults. The experimental prototype includes a five‐phase voltage source inverter (VSI) with protection circuits, current sensor board, and FPIM equipped with encoder. An open‐phase fault is observed in the machine, and the results recorded are in compliance with the simulation results achieved.