Matching Network Design and Parameter Optimization Method for Low-Frequency Active Sonar System

Research on active sonar systems (ASS) is gradually shifting from high-frequency to low-frequency operations. To address the challenges of narrow working bandwidth and low transmission efficiency in low-frequency hydroacoustic transducers (LHT) for acoustic-electric conversion, a variable LC-type impedance matching network (VLCM) is proposed. This network aims to enhance both the operational bandwidth and filtering performance of the system. Additionally, a wide-bandwidth parameter optimization model (WPOM) based on an inverter utilizing sinusoidal pulse width modulation (SPWM) is introduced. This model aims to achieve a broader operational bandwidth, minimize fluctuations, and alleviate potential harmonic issues resulting from resonance. Given the multi-constraint and multi-objective nature of the model, an optimization algorithm based on Non-dominated Sorted Multi-component Search (NSMS) has been developed. Finally, simulations and experimental comparisons are conducted to evaluate the system's performance under wide bandwidth conditions. The results demonstrate that the proposed VLCM significantly improves transmission performance and stability without introducing harmonic distortion.