Discrete‐time current regulator with arbitrary poles placement for alternating current machines

Abstract

To pursue high-performance motor drive, the current regulators are designed directly in the discrete domain. However, few kinds of research are developed to achieve arbitrary poles placement simply. To fill this gap, the authors propose a discrete-time current regulator consisting of two parts: the main regulator used to obtain decoupling control of dq axes currents, and the bi-proper compensator applied to realise arbitrary poles placement. To strengthen the anti-disturbance ability of the current regulator, the active resistance is added to the inner feedback path. Combining the active resistance, a new zero-order-hold equivalent motor model is developed, based on which the main regulator is designed using the zero-pole cancellation method. Furthermore, in this way, decoupling control for the two control objectives of reference tracking and anti-disturbance is realised. To achieve fast tracking response and negligible overshoot, an easy-toimplement scheme that simplifies the tuning of the current regulator is proposed based on the arbitrary poles placement. Moreover, the current regulator can be treated as a two-degree-of-freedom controller with this scheme. Finally, the effectiveness and reliability of the proposed current regulator are validated by the simulation results and experimental results in an alternating current machine drive platform.