1. Applications, principles and structures of piezoelectric transformers

1.1 Applications

The appearance of the first piezoelectric transformers coincided with the development, in the 1950s, of ferroelectric ceramics of the perovskite crystalline family. It was in 1956 that C.A. Rosen proposed a step-up transformer structure, fabricated in a bar of barium titanate (BaTiO ₃ ), which demonstrated the interest of making, very simply, compact electrical transformers, of small dimensions and with good performance. However, the impact...