Low-frequency high-power compact transducer based on negative stiffness structure

High-power extremely low-frequency (ELF) sound sources are essential in marine engineering, and electromagnetic transducers (EMTs) are preferred over piezoelectric and magnetostrictive transducers because of their superior output power and compactness. However, achieving high sound pressure levels (SPLs) below 50 Hz in compact EMTs is challenging. In our study, EMT diaphragms were optimized using a negative stiffness structure (NSS) to reduce the stiffness of the vibration system, thereby reducing frequency requirements and increasing output power, as validated by finite element analysis. The NSS diaphragm significantly outperformed conventional designs, increasing transducer output power by 216.23%, achieving a maximum SPL of 170 dB and over 160 dB from 4 to 50 Hz. With dimensions of 150 mm radius and 200 mm height, the EMT is an example of compact design. This research has successfully developed a low-frequency, high power, compact EMT that will enhance offshore technology and research and provide an improved solution for high power ELF sound sources, significantly advancing EMT applications in marine engineering.