Discrete-Time Robust Adaptive Current Control of Wound Rotor Synchronous Generator with Active Rectifier

The wound rotor synchronous generator (WRSG) has severe parameter perturbation, resulting in poor current loop robustness of active rectifier based on typical complex vector (CV) current regulator. Additionally, the CV principle is not fully applicable to WRSG with strong saliency ratio. In order to overcome this barrier, this paper proposes a discrete-time robust adaptive (DRA) current regulator that automatically tunes the loop gains based on Lyapunov stability theory without parameter estimation, ensuring system stability while improving anti-interference ability. Machine saliency can be ignored due to the adaptive characteristics of the DRA regulator. The adaptive law is directly derived in the discrete-time domain to ensure the accuracy of the design and can be directly applied to digital control system. Finally, experimental verification is conducted on the power generation platform of WRSG, and the results show that the proposed scheme has excellent steady-state performance, and both armature current harmonics and excitation current ripple are restrained. Moreover, it has strong robustness when the system parameters change.