Improved Temperature Dependence of Piezoelectric Element for Pressure Sensor

Abstract

The temperature dependence of the d33 constant was decreased by connecting a piezoelectric element to a temperature compensating capacitor in series. A bilayered composite piezoelectric element consisting of piezoelectric and dielectric ceramic layers was constructed to reduce the temperature dependence of the d33 constant. The temperature dependence of the d33 constant was thus reduced to less than 3% over the temperature range of -30 to 180° C. Furthermore, the temperature dependent properties of a combustion pressure sensor for an automobile engine based on the composite piezoelectric element developed in this study were discussed.