Parameter Identification Method for DTP-PMSM Based on High-Frequency Harmonic Voltage Signal Injection

Due to the advantages of reduced torque ripple, enhanced fault tolerance, and superior power density, dual three-phase permanent magnet synchronous motors (DTPPMSMs) systems are widely adopted in high-power applications. However, during motors operation, critical parameters exhibit time-varying characteristics due to multi-factor influences such as temperature rise effects and magnetic saturation effects, leading to degradation of control performance. To achieve realtime acquisition of motor parameters, this paper proposes a novel online parameter identification method based on highfrequency harmonic voltage injection. By utilizing the inherent harmonic subspace of space vector decoupling (VSD), voltage signals are injected into the torque-insensitive harmonic plane to prevent coupling with fundamental plane excitation. Through extraction of current responses at the injection frequency, harmonic impedance components are derived via frequencydomain demodulation, enabling precise estimation of stator resistance and leakage inductance. This method effectively isolates identification parameter from non-ideal error sources by frequency-selective processing.