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，设计了一种基于被动压电陶瓷片的多模态朗之万超声换能器。通过控制谐振频率比，可以动态匹配换能器的两种纵向振动模式，产生稳定的双频超声，这对探索声悬浮、超声空化等声学新应用有很大帮助。此外，通过调节两种模式的准锯齿波输出位移来实现精确驱动。原型压电驱动器通过动态谐振频率控制，在长时间工作下实现稳定输出。

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.