【目的】分数槽集中绕组(FSCW)双转子电机由于其独特的绕组分布导致气隙中含有丰富的磁动势谐波,在直接起动时,电机将会产生大量的冲击电流和转矩脉动。针对上述问题,本文将以硬起动与软起动为基础分析这两种起动方式下的电磁转矩特性,判断这两种起动方式是否有利于电机的稳定运行,并验证虚位移法在这两种起动方式下是否成立。【方法】本文首先介绍FSCW轴向双转子电机的基本结构及工作原理,并根据绕组理论建立了电机的数学模型,根据仿真结果分析了软硬起动的暂态过程与稳态过程以及该模型在软硬起动情况下不同定转子轴线夹角的转矩特性;然后,基于虚位移法推导出电磁转矩的表达式;最后结合虚位移法和仿真结果讨论了两种起动方式下的电磁转矩。【结果】由仿真数据可知,电机在硬起动的瞬间,电磁转矩急剧增加,并且后续转矩波形波动较大,存在明显的振荡。随着时间的推移,转矩波动逐渐平稳并进入稳态,其暂态峰值约为稳态峰值的2倍。在软硬起动条件下,电磁转矩的仿真结果略小于通过虚位移法计算出的结果。当定转子的轴线夹角发生变化时,仿真波形的峰值与波动也发生了明显的变化。【结论】结果表明,硬起动不利于该电机的稳定运行,定转子的轴线夹角会影响电磁转矩的大小和转矩脉动。电磁转矩的仿真值与理论值吻合度较高,推导出的表达式具有较高的准确性,为后续计算电机的电磁转矩提供了参考。

[Objective] Fractional-slot concentrated winding (FSCW) dual-rotor motor, due to its unique winding distribution, generates abundant magnetomotive force harmonics in the air gap. During direct starting, the motor generates a large amount of inrush current and torque pulsation. To address this issue, this paper analyzes the electromagnetic torque characteristics under two starting methods-hard starting and soft starting-to evaluate whether these methods are conducive to the stable operation of the motor. Additionally, the validity of the virtual displacement method under these two starting conditions is verified. [Methods] This paper first introduced the basic structure and working principle of the FSCW axial dual-rotor motor. A mathematical model of the motor was then established based on winding theory. Based on simulation results, the transient and steady-state processes of hard and soft starting were analyzed, as well as the torque characteristics at different stator-rotor axial angles under both starting conditions. Next, the electromagnetic torque expression was derived based on the virtual displacement method. Finally, the electromagnetic torque under both starting conditions was discussed by combining the virtual displacement method and simulation results. [Results] Simulation data showed that during hard starting, the electromagnetic torque increased sharply, and the subsequent torque waveforms exhibited significant fluctuations and noticeable oscillations. Over time, the torque fluctuations gradually stabilized and reached a steady state, with the transient peak about twice the steady-state peak. Under both hard and soft starting conditions, the simulated electromagnetic torque was slightly lower than the result calculated by the virtual displacement method. The peak values and fluctuations of the simulation waveform showed significant variations when the stator-rotor axial angle was altered. [Conclusion] The results indicate that hard starting is not conducive to the stable operation of the motor. The stator-rotor axis angle affects both the magnitude of the electromagnetic torque and the torque pulsation. The simulated electromagnetic torque aligns well with the theoretical value, and the derived expression shows high accuracy, serving as a reference for subsequent calculations of the motor's electromagnetic torque.

中国博士后科学基金面上项目(2017M621086);江苏省配电网智能技术与装备协同创新中心开放基金项目资助(XTCX202405)