大容量高速电机转子截面突变处刚度特性及等效模型

转子梁单元模型因计算效率高等优点在大容量高速电机转子动力学优化设计中被广泛应用,其对转子截面突变处的力学连续性假设使得弯曲刚度被过高估计,工程上采用了过渡轴段的等效模型但仍存在较大误差,对此,基于欧拉梁和铁木辛柯梁理论对阶梯转子的刚度特性进行分析,并通过与实体单元结果对比,细化过渡轴段模型参数,实现基于修正梁模型的转子弯曲刚度的精确计算。计算结果证明所建模型兼顾了转子实体单元有限元模型的高计算精度和梁单元模型的高计算效率的优点。

The Bending Stiffness and Optimal Equivalent Parameters of Stepped Rotor Segments by Beam Elements in High-speed Large Generator

The rotor beam element model is widely used in the rotor dynamics optimization design of large-capacity high-speed motors due to its high computational efficiency.The assumption of deflections consistency on the rotor segments where the cross section suddenly changes makes the bending stiffness overestimated.The equivalent model with a transitional shaft segment is used in practice at present However there was still error.For this reason,the stiffness characteristics of the stepped rotor segments are analyzed based on the Theory of Euler-Bernoulli Beam and the Theory of Timoshenko Beam.The optimal equivalent parameters of the transitional rotor segment are refined by comparison with the results of the solid element.The calculation results prove that the model has both the high calculation accuracy of the finite element model of the rotor solid element and the high computational efficiency of the beam element model.