Discrete-Time Complex Vector Dual Internal Mode Decoupling Control Method with Delay Compensation for CSI-Fed PMSM System

This paper proposes a dual internal model (DIM) decoupling control method with delay compensation, in which the internal model principle is applied to both the voltage loop and the current loop to solve the high order and strong coupling problems of the permanent magnet synchronous motor (PMSM) system fed by the current source inverter (CSI). By means of deriving the complex-vector model of the CSI-fed PMSM system, the influence of cross-coupling caused by coordinate transformation is analyzed and the decoupling performance of the DIM decoupling control method is quantitatively evaluated. To overcome the influence of control delay and angle coupling, the model of the DIM decoupling control method in the discrete domain is derived. The codesign method of controller parameters and the delay compensation coefficient is introduced and compared with the traditional decoupling method. Finally, the experimental results show that the proposed decoupling method can improve the control performance in both dynamic and steady states.