Fuzzy logic based efficiency optimization and improvement of dynamic performance of IPM synchronous motor drive

This paper presents fuzzy logic controllers (FLCs) based both efficiency optimization and high performance speed control of an interior permanent magnet synchronous motor (IPMSM) drive. In order to maximize the efficiency during both transient-state and steady-state operations while meeting the speed and load torque demands two fuzzy logic based efficiency controllers are designed to generate the optimum magnetizing current, which is d-axis component of the stator current, i_d. The steady-state fuzzy efficiency controller (SSFEC) is a search controller operating in steady-state to minimize the drive power losses to achieve higher efficiency by reducing the stator flux. The transient-state fuzzy efficiency controller (TSFEC) is a controller operating during transient-state to increase the flux, depending on the speed error and its derivative to let the drive track the reference command. In order to achieve high dynamic performance another FLC is used which controls the torque component of the stator current based on speed error and its derivative. Furthermore, a torque compensator is used to reduce the torque and speed ripples. The efficacy of the proposed IPMSM drive for efficiency optimization, and robustness is tested in both simulation and experiment.