<p>Torque ripple in permanent magnet synchronous motors (PMSMs) under field-oriented control may arise from various factors, such as cogging torque and parameter mismatch. Among them, inverter nonlinearity and stator phase resistance asymmetry are two common factors that introduce periodic current harmonics and degrade torque smoothness. Existing studies primarily focus on harmonic issues caused by a single source. Therefore, a unified harmonic model considering both inverter nonlinearity and stator phase resistance asymmetry is established to analyze the current and torque ripple characteristics. To suppress the dominant even-order harmonics in <i>dq</i>-axis currents, an improved repetitive controller incorporating a feedforward structure and a half-period delay strategy is developed and connected in parallel with the proportional–integral current controller. Compared with the conventional repetitive controller, the proposed method achieves higher resonant gain, wider bandwidth and reduced memory requirements. The paper also details controller parameter tuning, stability analysis and digital implementation using a fractional delay unit. The proposed method is experimentally validated on a rapid control prototyping platform under various operating conditions. Experimental results demonstrate that this method effectively suppresses harmonic currents and significantly reduces torque ripple, providing a practical solution for torque ripple suppression in PMSMs.</p>