Classification and review of MTPA algorithms for synchronous reluctance and interior permanent magnet motor drives

The MTPA algorithms are attractive solutions for reaching very high energy efficient drives. The paper presents a general formulation of the MTPA problem statement, including also the magnetic saturation in the formulation. A classification and a review of the MTPA techniques is proposed in this paper. A distinctive feature of the proposed classification is the highlighting of the most important characteristics (e.g. needs of motor parameters, signal injection, self-commissioning tests, etc.) of each technique. Also, offline and online techniques are thoroughly discussed. All synchronous motors, with or without permanent magnets, are considered.