High-Power Operation of Acoustic-Electric Power Feedthroughs Through Thick Metallic Barriers

Throughout the last few years there has been a significant push to develop a means for the transmission of electrical power through solid metallic walls using ultrasonic means. The bulk of this effort has been focused on using two coaxially aligned piezoelectric transducers on opposite sides of a thick metallic transmission barrier, where one transducer serves as the “transmit” transducer and the other as the “receive” transducer. Previous modeling has predicted reasonably high power transfer efficiencies through the wall using this type of “acoustic-electric channel” to be possible at low power levels, which implies that channel component operates in a linear range with little concern of failure. High-power testing of two acoustic-electric channels has been done in an effort to determine power limits on such channels and to determine levels at which non-linear effects on the piezoelectrics become non-negligible. The tested channels are characterized by the “power density” imposed on the transmit transducer, that is, the power applied per unit area, as the values found for maximum power density are considered to be independent of transducer radii. The constructed channels are shown to be capable of transmitting large amounts of power (over 100 watts) without failure; and further, extrapolation of the results to channels with larger diameter transducers predicts power transfer of 1 kW to be highly feasible.