Study on Dual-Stage Amplification Cascaded Piezoelectric Transducer for High-Power Applications

To reduce the size and enhance the efficiency of cascaded sandwich transducers with conical horns, a novel structural configuration of such transducers was investigated. This transducer incorporates two sets of piezoelectric stacks, enabling two-stage amplification for improved efficiency. An equivalent circuit model for the cascaded sandwich transducer with a conical horn was established, systematically deriving analytical expressions for core performance parameters including input impedance, velocity amplification ratio, and resonant characteristics. Through theoretical and simulation analyses, the dynamic influence of key structural parameters on electromechanical energy conversion efficiency was determined, specifically the output radius of the second-stage, the relative position of the variable cross-section of two sets of piezoelectric ceramic sandwich structures, and the spacing between the two sets of piezoelectric ceramics. Furthermore, a performance optimization strategy based on piezoelectric single-crystal materials was proposed. Numerical simulations validated against theoretical models revealed the governing principles of piezoelectric materials on transducer performance. Experimental results demonstrate excellent agreement between the operational characteristics of the optimized transducer and predictions from both theoretical models and finite element simulations. This work holds guiding significance for optimizing multi-mode transducers and demonstrates promising application potential in high-power ultrasonic fields.