Experimental approach for thermo-electro-mechanical characterisation of piezoelectric transducers

Abstract Piezoelectric transducers are subject to increasingly stringent performance requirements. High-power, high-temperature and high-precision applications are becoming more important. Thus, the maximum permissible temperature of the transducer and the temperature-dependent performance and behaviour can become relevant in piezoelectric transducer design here, which is why thermo-electro-mechanical characterisation is becoming essential for the development of piezoelectric systems. In the current state of the art, electro-mechanical piezoelectric characterisation is common, whereby the influence of thermals is disregarded. In this context, an experimental setup has been developed that enables characterisation of the combined thermal, electric and mechanical behaviour of piezoelectric transducers. The focus of the work here is a non-destructive characterisation of piezoelectric transducers at their electric load, which maps the special requirements of the application with its thermal and mechanical load cases by using an additional load actuator and additional thermal elements. The experimental setup has a modular design so that a large number of different designs and sizes of piezoelectric transducers can be analysed, with the focus being on prismatic and cylindrical longitudinal piezoelectric stack actuators. Beyond that, the experimental setup developed in this work is also suitable for investigating cooling methods, as we observed, that more and more concepts for cooling piezoelectric transducers are being developed that need to be analysed experimentally. In summary, this paper describes the development of the experimental setup with all implementation measurements and an initial piezoelectric transducer test using a PZT stack actuator, to show the potential.