Sensitivity and Robustness Analysis of Proportional–Resonant Current Control for Six- Phase IMs

The development of advanced current control strategies for six-phase induction machines (IMs) has been driven by the need to take full advantage of their inherent efficiency, fault tolerance, and reliability. In that sense, proportional—resonant (PR) controllers, known for their current tracking accuracy in a stationary reference frame, are particularly well-suited to multiphase drive applications. This work presents a sensitivity and robustness analysis of a PR current controller designed for six-phase IM drives. The PR is evaluated through simulation under four rigorous test scenarios. Two tests assess current tracking accuracy and dynamic performance at low and high speeds, including full-speed reversals between ±500 r/min and ±1000 r/min. The remaining tests introduce ±50% uncertainties in stator resistance and magnetizing inductance to evaluate robustness against parameter mismatches. Across all scenarios, the controller achieves total harmonic distortion (THD) below 0.35% and root mean square error (RMSE) under 0.02 A in both the (α-β) and the (x-y) plane. Even under abrupt speed reversals, current stability is restored in approximately 2.5 seconds, demonstrating robust dynamic behavior. Compared with more complex model-based approaches, the proposed PR control scheme achieves comparable tracking accuracy and robustness while offering simpler implementation and lower computational demand. These results validate the feasibility of PR-based control for high-performance multiphase drives operating under variable conditions.