To improve the integrated performance of a representative bimodal linear ultrasonic motor under continuous operation, this paper proposes a novel dual-frequency asymmetric excitation method for such motors which can operate under traditional single-phase asymmetric or two-phase symmetric excitation modes. In particular, two optimal excitation frequencies from loss reduction aspect of the stator under actual contact-based operating conditions are determined by the corresponding equivalent circuit model. The effects of the proposed excitation mode on the motion trajectory of the driving tip and the motor performance are analyzed in detail. Both the simulation and experimental results show that the motor has better mechanical characteristics with the proposed excitation method comparing to traditional excitation methods. Furthermore, the experimental results indicate that the motor demonstrates acceptable temperature characteristics and operating stability under the proposed excitation method with calculated optimal frequencies.

中文翻译：

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使用双频非对称激励方法的双模线性超声电机综合性能改进

为了提高具有代表性的双模线性超声电机在连续运行下的综合性能，本文提出了一种新的双频非对称励磁方法，该方法可以在传统的单相非对称或两相对称励磁模式下运行。具体而言，在实际基于接触的工作条件下，定子损耗降低方面的两个最佳励磁频率由相应的等效电路模型确定。详细分析了所提出的激励模式对驱动尖端运动轨迹和电机性能的影响。仿真和实验结果均表明，与传统励磁方法相比，采用所提出的励磁方法的电机具有更好的机械特性。此外，