Fuzzy Logic-Based Efficiency Optimization and High Dynamic Performance of IPMSM Drive System in Both Transient and Steady-State Conditions

This paper presents both the efficiency optimization and high performance speed control of an interior permanent-magnet synchronous motor (IPMSM) drive, based on fuzzy logic controllers (FLCs). 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 the d-axis component of the stator current id. The steady-state fuzzy efficiency controller is a search controller operating only in steady state to minimize the drive power losses to achieve higher efficiency by reducing the stator flux. The transient-state fuzzy efficiency controller operates only during transient state to increase the flux, depending on the speed error and its derivative. In order to achieve high dynamic performance, another FLC is used as speed controller, which controls the torque component of the stator current. 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.