A 2-D fuzzy logic based MRAS scheme for sensorless control of interior permanent magnet synchronous motor drives with cyclic fluctuating loads

Model reference adaptive system (MRAS) is usually employed for the rotor position/speed estimation in sensorless interior permanent magnet motor (IPMSM) drives, and the adjustment of control parameters in MRAS is a key issue for the IPMSM drive system with the cyclic fluctuating load. In order to avoid the complicated manual tuning of the control parameters, a new MRAS scheme based on fuzzy logic is proposed in this paper, in which a fuzzy controller replaces the conventional PI regulator. To implement this new MRAS scheme, a two-dimensional (2-D) fuzzy rule is designed. The proposed control scheme is employed in the IPMSM drives with the cyclic fluctuating load, such as compressors. In order to lower the motor speed ripple caused by the cyclic fluctuating load, a feed-forward compensation strategy with the load-matching motor output torque pattern is developed. Experimental results demonstrate the feasibility and effectiveness of the proposed fuzzy logic based MRAS scheme, which shows that the rotor position estimation error is limited within a very low level.