Improvement mechanism of energy conversion efficiency in ultrasonic motor with flexible rotor
Improvement mechanism of energy conversion efficiency in ultrasonic motor with flexible rotor
复制标题
柔性转子超声波电机能量转换效率的提高机理
DOI：
10.1016/j.ultras.2021.106659
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发表时间：
2022-03-01
期刊：
影响因子：
4.2
通讯作者：
Qiu, Jinhao
中科院分区：
文献类型：
--
作者：
Chen, Hucheng;Nie, Rui;Qiu, Jinhao
柔性转子因其较高的能量转换效率而被广泛应用于行波旋转超声电机（TRUMs）中，但关于柔性转子如何提高超声电机能量转换效率的研究报道较少。在这项研究中，我们调查的能量转换效率的提高机制，在TRUM与柔性转子。建立了压电耦合定子、转子、摩擦层以及定子与摩擦层的刚弹接触界面之间全耦合的三维有限元模型。为了分析TRUM效率提高的机理，提取了接触界面和转子振动信息。以TRUM-60为例，采用瞬态求解法和模态分析法对模型进行求解。结果表明，当定子模态为B-09时，柔性转子模态为B-19。TRUM的能量转换效率从模型解的输出功率与电输入功率的比率获得。使用三维振动测量和能量转换效率实验的结果进行了验证。仿真结果表明，与刚性转子电机相比，柔性转子电机提高了能量转换效率，这主要归因于两个方面：一是柔性转子减小了转子与定子的轴向振幅比;二是柔性转子减小了径向摩擦。研究结果揭示了柔性转子对输出效率的影响，为转子设计提供了指导。
Flexible rotors are widely used in traveling wave rotary ultrasonic motors (TRUMs) because of their higher energy conversion efficiency; however, there have been few reports on how flexible rotors improve the energy conversion efficiency of ultrasonic motors. In this study, we investigate the improvement mechanism of energy conversion efficiency in TRUMs with flexible rotors. A 3D finite element (FE) model with full coupling among a piezoelectric coupled stator, rotor, friction layer, and the rigid-elastic contact interface of the stator and friction layer is established. To analyze the mechanism by which the efficiency of the TRUM is improved, the contact interface and rotor vibration information are extracted. Taking TRUM-60 as an example, the transient solution method and modal analysis method are used to solve the model. It is found that when the stator mode is B-09, the flexible rotor mode is B-19. The energy conversion efficiency of the TRUM is obtained from the ratio of output power to the electrical input power of the model solution. The results are validated using 3D vibration measurements and energy conversion efficiency experiments. The simulation result shows that the motor with flexible rotor improves the energy conversion efficiency compared with the motor with rigid rotor, which can be attributed to two reasons: first, the axial amplitude ratio of the flexible rotor to the stator is reduced; second, the flexible rotor reduces the radial friction. This study reveals the influence of flexible rotor on the output efficiency and can thus provide guidance for rotor design.