Piezo-electric transformer with a high voltage boost ratio and free of cracks polarization

摘要

A driving section applied with an input a.c. voltage and a generator section for generating an output potential are incorporated in a piezoelectric ceramic transformer, and the generator section is polarized through a two-step polarizing technique where an electric field is created in the generator section in high temperature atmosphere and, thereafter, the temperature is decreased without changing the electric field, thereby saturating the polarization without a crack.