Consolidated SVPWM for Single-Phase Fault-Tolerant Control of CFNI-Based Inverter

Fault-tolerant control is essential for traction drive systems, which are pivotal components in electric vehicles and high-dependability applications. These systems face significant challenges, particularly under single-phase faulty conditions at either the machine or the inverter level, which can lead to performance degradation or system failure if not properly managed. This paper presents a fault-tolerant approach based on a consolidated space vector pulse width modulation (SVPWM) to enable the traction drive system to operate under single-phase faults. The proposed method leverages the capacitor-based four-leg neutral-point-connected inverter (CFNI) topology and integrates a remedial approach grounded in field-oriented control (FOC) to drive a permanent magnet synchronous motor (PMSM). The simulation results validate the effectiveness of the proposed method in maintaining reliable operation under fault conditions, preserving accurate speed and torque tracking with minimal deviations. Nevertheless, the elevated current stress observed during fault scenarios requires oversized inverter ratings. These findings demonstrate the robustness of the proposed SVPWM strategy implemented on the CFNI topology, confirming its viability for single-phase fault-tolerant traction drive applications.