This paper presents an analytical method to calculate the temporal and circumferential orders of the radial force density harmonics in switched reluctance machines (SRMs) without running the electromagnetic finite element analysis (FEA). The characteristics of the radial force density harmonics in several SRM topologies are investigated, including the 6/4, 24/16, and 6/14 internal-rotor (IR) SRMs, and 12/16 and 18/24 external-rotor (ER) SRM. The study shows that the temporal and circumferential orders of the radial force density harmonics depend on the pole configuration, the rotational directions of the rotor, the phase excitation sequence, and the rotor or stator radial force density waveform. The acoustic noise of a four-phase 8/6 internal-rotor SRM and a three-phase 12/16 external-rotor SRM was experimentally measured to validate the calculation of the temporal and circumferential orders of the radial force density harmonics. The proposed analytical method helps locate the possible radial force density harmonics of a given SRM configuration. In order to determine the dominant radial force harmonics, the proposed method should be complemented by analyzing the natural frequencies of the motor structure and the forcing frequencies of the radial force harmonics.

中文翻译：

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外转子和内转子开关磁阻电机中径向力密度谐波的时间和周向阶次解析计算


本文提出了一种无需运行电磁有限元分析 (FEA) 即可计算开关磁阻电机 (SRM) 中径向力密度谐波的时间和周向阶数的分析方法。研究了几种 SRM 拓扑中的径向力密度谐波特性，包括 6/4、24/16 和 6/14 内转子 (IR) SRM，以及 12/16 和 18/24 外转子 (ER) ）SRM。研究表明，径向力密度谐波的时间和周向顺序取决于极配置、转子的旋转方向、相励磁序列以及转子或定子径向力密度波形。通过实验测量了四相 8/6 内转子 SRM 和三相 12/16 外转子 SRM 的声学噪声，以验证径向力密度谐波的时间和周向阶次的计算。所提出的分析方法有助于定位给定 SRM 配置的可能径向力密度谐波。为了确定主要的径向力谐波，应通过分析电机结构的固有频率和径向力谐波的强制频率来补充所提出的方法。