High-Damped Complex Vector Current Regulator for PMSM Based on Active Damping Function

The complex vector current regulator (CVCR) has been widely used in high-performance PMSM drives because of its simple structure and excellent decoupling property. However, the CVCR's disturbance rejection ability is insufficient due to the plant's low-dynamic and poorly damped pole. To address such problem, an active resistance compensation is requisite. This article proposes a high-damped complex vector (HDCV) current regulator. By reconstructing the damping structure, it improves the characteristic of the conventional active resistance complex vector (ARCV) regulator. The eigenvalues of disturbance rejection function of HDCV achieve the higher natural angular frequency and damping ratio. The frequency response demonstrates that HDCV outperforms ARCV in disturbance rejection under similar noise suppression conditions. It also achieves the extended damping coefficient range without compromising system stability. To broaden HDCV's applications, an improved current predictor based on extended state observer is introduced in the damping function, ensuring superior regulation performance even at low sampling frequencies. The experimental results validate the correctness of damping compensation method and demonstrate the superiority of the proposed scheme over conventional methods.