Design of full bridge high voltage pulser for sandwiched piezoelectric ultrasonic transducers used in long rail detection.

Abstract The full bridge high-voltage pulser for excitation of sandwiched piezoelectric ultrasonic transducers (SPUTs) used in long rail detection is designed. By using the single SPUT and pitch-catch setup test platforms, the comparison between the designed pulser and the conventional pulser is performed in time and frequency domains. Then the effect of turn-off snubber circuit on the designed pulser is investigated using simulation and experiment. To further improve power transmission efficiency for SPUTs, electrical impedance matching (EIM) network and snubber circuit are considered. Compared with the conventional pulser, the designed pulser has more superior performance which makes peak-to-peak, frequency spectrum amplitude and power spectrum density of the received signal increase 31.8%, 34.1% and 32.9%, respectively at 50 m test distance. It can be found that turn-off snubber circuit can efficiently reduce switch loss and the simulated results are well consistent with the measured ones. In addition, the combination of EIM network and snubber circuits can make power transmission efficiency higher. It can be concluded that the designed pulser can well meet the excitation requirements of SPUTs and contributes to reduce algorithm complexity and hardware costs. [ABSTRACT FROM AUTHOR]