Power enhancement of piezoelectric transformers by adding heat transfer equipment.

It is known that piezoelectric transformers have several inherent advantages compared with conventional electromagnetic transformers. However, the maximum power capacity of piezoelectric transformers is not as large as electromagnetic transformers in practice, especially in the case of high output current. The theoretical power density of piezoelectric transformers calculated by stress boundary can reach 330 W/cm(3), but no piezoelectric transformer has ever reached such a high power density in practice.

Analyses of the heat dissipated by losses in a piezoelectric transformer.

In this paper, a new approach to the thermal management of piezoelectric transformers is proposed. Starting from the electromechanical equations, including mechanical and dielectrical losses, and knowing the piezoelectric material characteristics, an analytical model was developed and the theoretical profile of the heat sources was deduced. To check these theoretical points of view, a thermal characterization of a Rosen-type piezoelectric transformer was done.