In this paper, magnetic field analysis of a new doubly salient permanent magnet (DSPM) motor is carried out based on finite element method (FEM). Hence, the corresponding static characteristics, including PM flux linkage, self-inductance, mutual inductance, and static torque are deduced (the interaction between the PM field and armature field are taken into account). New methods for measuring the motor inductance are also proposed. The theoretical analysis is verified by experimental results.

提出了一种新型分裂绕组双凸极变速永磁（doubly salient permanent magnet，简记为DSPM）电机，对其磁场、静态特性、控制策略等进行了系统深入的理论和实验研究。在理论上，给出了DSPM电机的稳态和动态数学模型，进而导出了该电机的输出方程，并论证了采用分裂绕组拓展电机转速范围的可行性。用有限元法分析了电机磁场，计及该电机所特有的外漏磁。根据DSPM电机工作原理和静态特性，提出相应的控制策略，制定了控制方案，并在以单片机为核心的控制器上实施。针对4相8/6极电机的特点，提出了无中线四相半桥式功率变换器拓扑结构，简化了控制系统。样机实验结果不仅验证了理论分析的正确性，而且表明该新型电机驱动系统具有优良的稳态和动态性能，在很宽的功率范围内具有高效率，分裂绕组能有效拓展电机行范围。

In this paper, various flux-weakening techniques available for wide speed operation of the doubly salient permanent magnet (DSPM) motor are reviewed. A new split-winding topology capable of widening the speed range is proposed, which is valid not only for the DSPM motor with stationary PMs, but also for that with rotary PMs. Based on the parameters obtained by finite element analysis, the performance of the proposed DSPM motor is analyzed. The results show that this motor combines the features of wide speed range, high efficiency, simple structure, and low cost.

This paper proposes a new 8/6-pole doubly salient permanent-magnet (DSPM) motor drive, which offers the advantages of higher power density, higher efficiency, and wider speed range. The corresponding control and operation of the motor drive are presented. A variable proportional-integral (PI) controller combined with bang-bang control for the DSPM motor drive is developed. Two operation modes, namely, four-phase and two-phase operation modes, are proposed for the 8/6-pole DSPM motor drive. The drive system is implemented and tested. The results show that the developed control scheme can operate the DSPM motor properly, and the DSPM motor drive offers high efficiency over wide power range and good dynamic performance. Furthermore, the two-phase operation mode of the 8/6-pole DSPM motor offers the possibility of eliminating the torque ripple of the motor drive.

In a doubly salient permanent-magnet (DSPM) motor drive, it is difficult to get satisfied control characteristics by using a normal linear proportional plus integral (PI) controller due to the high nonlinearity between speed and current or torque. Hence, a new self-tuning fuzzy PI controller with conditional integral, which is performed by a single-chip N87C196KD, is proposed. The initial parameters of the controller are optimized by using genetic arithmetic. Simulation and experiments on the newly proposed 8/6-pole DSPM machine have shown that the proposed new self-tuning fuzzy PI controller offers better adaptability than the normal linear PI control and that the developed motor drive offers better steady-state and dynamic performances.