Research on Low Temperature Characteristics and Application of Temperature Sensor in Alpine Region

Alpine regions have higher requirements on the temperature tolerance of sensors, especially the durability of sensors and the accuracy of measurement data under low temperature conditions, which directly affect the long-term stable operation of power transmission and transformation equipment. In this paper, the application of temperature sensors in alpine regions is investigated, and the application principle types, application quantities, main installation locations, low temperature operation time, low temperature failure conditions and treatment measures of sensors in alpine regions are mastered. The low temperature characteristics of optical fiber temperature sensor and surface acoustic wave temperature sensor (referred to as SAW temperature sensor) were tested at $- 50^{\circ}\mathrm{C} \sim 0^{\circ} \mathrm{C}$, and the sensor output characteristics at different temperatures and different low temperature examination time were studied. The results indicated that the low temperature performance of optical fiber temperature sensor was relatively stable at $- 50^{\circ}\mathrm{C} \sim 0^{\circ} \mathrm{C}$, but the package at low temperature was not tight and the temperature drift of resistance exceeded the accuracy range. The low temperature performance of SAW temperature sensor was acceptable at $-30^{\circ}\mathrm{C} \sim 0^{\circ} \mathrm{C}$, but poor at $-30^{\circ}\mathrm{C} \sim 40^{\circ} \mathrm{C}$. With the decrease of temperature, the measurement error of the sensor increased sharply. The metal film inside the sensor had a slight mass change after the low temperature test, resulting in a mass loading effect, and the resonant frequency was shifted.