A current controller design for current source inverter-fed PMSM drive system

A current source inverter (CSI) requires a capacitor filter for the commutation of switching device as well as attenuating switching harmonics. This paper presents the current controller design of CSI-fed PMSM (Permanent Magnet Synchronous Machine) drive system in order to attenuate resonance due to the LC filter. Basically, the CSI-fed drive system is modeled as a 2
^nd
order system. Hence a multi-loop current controller design using a pole/zero cancellation method is proposed with a transfer function matrix. To compensate the cross-coupling term, two types of controller are implemented using different decoupling method. Additionally, active damping methods are proposed to enhance the stability of the system. To evaluate the effectiveness of the proposed current controller, computer simulation and experiment have been performed and the results are discussed.