A Computationally Efficient Full-Speed Domain Control Method for PMaSynRM Considering Magnetic Saturation

The permanent magnet-assisted synchronous reluctance motor (PMaSynRM) has a wide speed range. Accurately resolving the optimal current operation point across the full-speed domain is crucial to ensuring the motor's efficient and reliable operation. Due to the partial neglect of the magnetic saturation characteristics in PMaSynRM, the operating point obtained by existing methods is suboptimal. This article presents a set of full-speed domain control methods. First, this article proposes maximum torque per ampere (MTPA) and maximum torque per voltage (MTPV) criteria that consider the partial derivative term of the inductance with respect to current, which has been ignored in previous methods. Furthermore, an initial iteration point optimization technique is proposed to reduce the increased computational burden resulting from more complex criteria, ensuring the algorithm's real-time implementation. The proposed method realizes an accurate and real-time solution of the optimal operating point. Compared to traditional methods, the proposed method has a higher torque enhancement in the MTPA region and a higher MTPV critical speed. The effectiveness of the proposed method is experimentally verified in a 5.5 kW PMaSynRM.