Analysis of high efficiency and low cost drive system of IPMSM by using two-steps model predictive torque control

In this paper, an optimal reference stator flux strategy is proposed to improve the drive system efficiency with two-steps model predictive torque control (MPTC). By compensating the step delay and reducing inverter losses, the control performance of two-steps MPTC is improved. Theoretical basis of efficiency optimization based on optimal stator flux is analyzed by mathematical method under variable speed and torque. The performance of loss model (LM) is improved by taking into account the current step delay. Based on the easily implementable LM, the controllable electrical losses which consist of copper loss, iron loss and permanent magnet (PM) loss have been minimized under optimal stator flux. A low cost (LC) interior permanent magnet synchronous machine (IPMSM) is introduced and tested. The dynamic performance of the proposed two-steps MPTC with loss model control (LMC) is validated experimentally.