A Low Complexity Two Step Predictive Torque and Flux Control Scheme for PMSM Drive

Abstract

Nowadays, finite control set model predictive control techniques are widely used for variable speed Permanent Magnet Synchronous Motor (PMSM) drive applications due to its simple, intuitive algorithm and easy inclusion of motor objectives. In conventional predictive torque control (PTC) method, both torque and flux are controlled by a cost function optimization, where it introduces weighting factors. The selection and tuning of weighting factors is difficult since it affects torque and flux performance of PMSM drive. In this article, a two-step PTC for PMSM drive is proposed, where the flux control objective is replaced with the reactive torque component. Therefore, optimal torque and flux controlling of PMSM is achieved with similar units for both control objectives. Hence, it eliminates weighting factor tuning problem and reduces the average torque and flux ripples over a two sample instants. Additionally, the reduced voltage vector strategy is proposed, so that increased computational efficiency is achieved. To validate the proposed methodology, simulations and experimental tests are conducted for three phase PMSM drive. The obtained simulation and experimental results justify an improved torque and flux response with reduced computational burden when compared to existing PTC methods.