Harmonic Suppression Deadbeat Predictive Current Control with Enhanced Extended State Observer for PMSM Drives

In direct-drive train, due to the cancellation of gearbox, the harmonic torque frequency may coincide with mechanical structure modal frequency, resulting in electromechanical coupling resonance. The conventional deadbeat predictive current control (DPCC) strategy fails to mitigate harmonic-induced resonances due to their limited observation capability for high-frequency disturbances. To solve this challenge, a harmonic suppression DPCC (HS-DPCC) is proposed in this paper. To achieve high robustness and resonance suppression, the enhanced extended state observer (E-ESO) is embedded with HS-DPCC. In E-ESO, the quasiresonance controller is utilized to magnify the harmonic torque observation capability. By feeding observed total disturbances back into the HS-DPCC control law, the scheme achieves significant suppression of low-order harmonic torques and high robustness against inductances and flux-linkage perturbations. Simulation results demonstrate effective resonance suppression at the resonance frequency, confirming the method's potential for high-precision motion control applications.