Dynamic resonant frequency ratio control for high-power piezoelectric devices

基于所提出的谐振频率比控制方法，改进了高频交流开关短路，设计了一种带被动压电陶瓷片的多模态Langevin超声换能器，通过控制谐振频率比，实现换能器两个纵向振动模态的动态匹配，产生稳定的双频超声，这对于探索声悬浮、超声空化等声学领域的新应用具有重要意义，并通过调节两种模式输出的准正弦波位移实现了精确驱动。通过动态谐振频率控制，实现了压电驱动器的长期稳定工作。

Based on the proposed resonant frequency ratio control method, we have improved the high-frequency AC switch short-circuit and designed a multimodal Langevin ultrasonic transducer with a passive piezoelectric ceramic piece.By controlling the resonant frequency ratio, the two longitudinal vibration modes of the transducer can be dynamically matched, and stable dual-frequency ultrasound can be produced, which is of great help for exploring new applications in acoustics such as acoustic levitation and ultrasonic cavitation.Furthermore, precise driving is achieved by adjusting the output quasi-sawtooth wave displacement of the two modes. By dynamic resonant frequency control, the prototype piezoelectric actuator achieves stable output under long-term operation.