Active broadband low-frequency smart transducer with negative capacitance

The effective stiffness and the natural frequencies of a piezoelectric system shunted with negative capacitance could be changed with the capacitance ratios. Integrated the shunted piezoelectric stacks with driven piezoelectric patches, a novel non-resonant smart transducer is put forward and its low frequency performance is enhanced obviously. The proposed smart transducer is simulated with multi-physics coupled finite element method. When negative capacitance is selected properly, the radiated sound pressure level of the smart transducer could be increased significantly in much wide band at low frequencies. The smart transducer can be used to generate high power, multi-frequencies sound signal simultaneously.