Simplified model-free predictive current control for synchronous reluctance motor drive systems

Abstract

Recently, an appealing switching strategy, named model-based predictive current control (MBPCC), has received much research attention in power electronics and drives. However, MBPCC usually requires system model (in discrete-time form) and the system parameters in its controller design. In order to eliminate these restrictions, a simplified model-free predictive current control (SMFPCC) is proposed for a synchronous reluctance motor (SynRM) drive system to reduce the switching frequency of the inverter and the computational load. For a six-switch three-phase inverter, it can generate eight switching states, including two zero-voltage vectors and six active-voltage vectors. Unlike the previous method developed in [1] that considers all switching states, the proposed SMF-PCC merely needs to premeditate four switching states in each sampling interval to achieve the improvement. In addition, as opposed to [1] that requires stator current detections twice in each sampling interval, the proposed method only needs to do so once. To the best of authors' knowledge, this is the first time of SMFPCC been carried out through a 32-bit microcontroller, TMS320LF2809, to the SynRM drive system. The experimental results show that the proposed SMFPCC performs better than the MBPCC does in terms of the current tracking.