Equivalent circuit with temperature parameters for piezoelectric sensor under space environment

The temperature dependence of the characteristics in a PZT-S piezoelectric ceramic vibrator with the transverse mode was investigated ranging from -100°C to 90°C using by thermal vacuum chamber to utilize the vibrator to the aerospace industries. As the results, at room temperature, the resonant and anti-resonant frequencies had the minimum value, whereas, the dielectric constant increased linearly in the given temperature range. The mechanical loss decreased linearly from 0.08 to 0.03. Through the regression analysis, the temperature dependence functions of the characteristics were found as linear and square regression functions. An equivalent circuit with thermal parts was derived by using those functions. Applying the equivalent circuit, the input admittance characteristics of the piezoelectric vibrator were calculated. It can be confirmed that this method is useful to estimate the characteristics change of the piezoelectric vibrator caused by the temperature change under the space environment.