摘要：Matching the output impedance of SONAR system’s transmitter with the input
impedance of high power electro-acoustic transducer is important to improve its
transmitting efficiency by maximizing the transfer of power. In this work, an attempt
has been made to match the output impedance of power amplifier (4 Ω)with the input
impedance of high power (2000 watts) and high impedance (1387 Ω with phase angle
of 85˚ at its resonant frequency i.e 2.5 KHz) Piezoelectric material based Electroacoustic
Transducer, by realizing a Broadband Matching Transformer. Designing of
the matching transformer is undertaken using Lump Circuit Modeling and Network
Theorem. Matching Transformer has been designed to meet the required specification
by sequentially following measurement of transducer’s impedance as a function of
frequency using Impedance Analyzer and computation of its equivalent circuit
element's values based on measured parameters of the transducer. Matching
transformer was developed using composite Iron alloy based C-type and Toroid-type
Cores. Impedance and phase angle of the tuned transducer were found to be equal to
3.6 Ω and phase angle of 14.5˚, respectively. It is pertinent to mention that no
significant influence of the core type variation was observed on results. Impedance
results of the tuned transducer were also taken as a function of frequency to evaluate
the broadband performance of the Matching Transformer. Source Pressure Level of
the resonating transducer with matching transformer was observed to increase from
137 to 164 dB/ˇPa @ 1m when gain of the amplifier was set on 6dB. Results of the
work are promising and expected to contribute a lot in the development of
Underwater Surveillance Systems in future.
