Current-source-inverter (CSI) is particularly widely used in medium voltage drive system with its low dv/dt and natural short circuit protection capability. However, the filter capacitor of CSI and the motor form a second-order system causing LC resonance problem. Meanwhile the maximum speed of CSI-fed PMSM is limited by the DC bus current and voltage. In this work, we propose a model predictive control (MPC) scheme for CSI-fed PMSM drive that involves capacitor voltage into state variable to suppress LC resonance. The reference capacitor voltage is calculated by the system mathematical model. Then a unified cost function is designed to achieve multi-objective optimization. Moreover, the d-axis stator current reference is obtained by system parameters to realize field-weakening operation. The proposed control scheme is verified by PLECS simulation, the results prove the effectiveness of this work.

current-source-inverter (CSI);permanent magnet synchronous machine (PMSM) drives;model predictive control (MPC);cost function;field-weakening