Modification of stator current for enhanced flux weakening

摘要

An electric machine assembly includes an electric machine having a stator configured to have a stator current and a controller configured to receive a torque command (T). The controller has a processor and tangible, non-transitory memory on which is recorded instructions for executing a method of modifying the stator current for enhanced flux weakening. The controller is programmed to obtain a base stator current [I_d^LU, I_q^LU] from a look-up table based at least partially on the torque command (T). The controller is programmed to obtain a characteristic angle (θ_i, i=1, 2, 3) based at least partially on a value of the torque command (T) and the base stator current [I_d^LU, I_q^LU]. A stator current modifier [ΔI_d, ΔI_q] is obtained based at least partially on the characteristic angle (θ_i, i=1, 2, 3) and a flux weakening factor (ΔI_S) such that: ΔI_d=(ΔI_S*cosine (θ_i)) and ΔI_q=(ΔI_S*sine (θ_i)).