Multilevel Converter for Excitation of Underwater Transducers

In this paper, a switch mode multilevel Power Amplifier (PA) system for driving underwater electro acoustic transducer is presented. This Switch Mode Power Amplifier (SMPA) can replace linear PA in the frequency range above 10 kHz and less than 200 kHz. The system uses class-S switching technique and has less switching transition losses compared to class-D and hence more efficient. The output voltage waveform is a staircase waveform which can be approximated to a sine wave. A staircase sine wave in place of square wave improves the quality of the waveform and reduces the need for higher filter components. The simulation of the proposed system has been carried out using MULTISIM.A prototype of 1kW, 5 level converter that uses a single power source is developed for exciting electro acoustic transducer. A digital controller (dsPIC30F2010) is used to generate the gating signals for the power devices (MOSFET) in the system, which provides programmability in selecting the pulse length, power, pulse repetition rate etc. The test results are presented at the end.