Design of Broadband Impedance Matching Network for High-Power Electroacoustic Transducers Based on Multi-Objective Optimization

Underwater sonar detection systems are constantly evolving towards wideband and high-power directions, to achieve long-distance and high-precision detection. Meanwhile, the demand for wideband detection also brings challenges to the impedance matching issue between power amplifiers and electroacoustic transducers. The traditional objective of impedance matching is to achieve resonance and resistance matching. However, it ignores the fact that it is the flatness of the output sound pressure level that directly determines the system bandwidth, rather than the impedance of the equivalent load. To address the issues, this paper proposes a design method for broadband impedance matching networks of electroacoustic transducers based on multi-objective optimization algorithms. Firstly, methods of impedance matching in microwave field and high-power underwater detection field are summarized. Secondly, the unique trade-off requirements for power factor and flatness of the sound pressure level in the high-power underwater detection field are transformed into a mathematical optimization problem. Thirdly, a multi-objective algorithm is adopted to optimize the best topology and parameter values of the impedance matching network. Finally, taking a piezoelectric transducer as an example, the effects of the impedance matching network on improving the power factor and adjusting the flatness of the sound pressure level are calculated.