Control and efficiency optimization strategy for permanent magnet brushless AC motors

The problem of efficiency optimization in vector-controlled permanent magnet brushless AC motor drive is investigated. A machine model which accounts for the effect of core losses is included in the development of a loss model controller that dynamically determine the optimal reference currents and voltages required for minimum electrical loss (copper losses and core losses). The effectiveness of the proposed scheme is validated by evaluation/comparison with traditional maximum torque/ampere and zero d-axis (i_ds=0) control methods.