一种开关磁阻电机非线性磁链与转矩建模方法

Novel method of modeling nonlinear flux linkage and torque for switched reluctance motor

开关磁阻电机(SRM)由于磁化曲线高度饱和非线性的特点,造成传统的电机性能分析和建模方法很难运用到SRM中。根据SRM磁链曲线的特点,提出了一种带修正因子的反正切函数来建立SRM模型的方法。在获得SRM 5个特殊转子位置处的9个磁链数据点的基础上,利用傅立叶级数分解和反正切函数来拟合SRM的磁链特性,并推导出电感和电磁转矩模型。该模型函数表达式简单、系数修改方便、计算精度高,并且能够直观的反映SRM的磁链、电感和转矩变化情况。以一台550 W、6/4极SRM为例,进行了仿真与实验比较,结果表明该模型能够很好的反映SRM的实际工作状况,验证了所建模型的精确性和有效性。

Because of the highly saturated magnetization and nonlinear flux characteristic, it is difficult to apply the traditional electric motor function analysis and modeling method to the switched reluctance motors （SRM）. This paper proposes an arc-tangent function with modifying factor to model the SRM based on the characteristic of flux linkage. The proposed model was built with only nine data points at five rotor positions, which utilized the Fourier series in expression of current with arc-tangent function. The inductance and torque models were also proposed from the fitting curve of flux linkage. This model function expression is simple and easy to modify the coefficient. This proposed model can reflect the regulation of flux linkage and torque. Taking a 550 W 6/4 poles SRM as an example, the simulation and experimental test show that this method is accurate.