Design of the Wireless Temperature Measurement Alarming System in the High-Voltage Transformer Substation

Abstract

Due to electric power overload and equipment aging, fire and explosion occur at transmission circuitry joints in high-voltage transformer substation caused by high temperatures accumulated at these spots. This frequently brings huge financial loss. Conventional far-infrared temperature detector is inefficient for its limited precision level and real-time temperature detection using fibre optic cable system appears to be too costly. This paper addresses the design of a wireless sensor network node and point-to-multipoint polling network using main elements of wireless communication module STR-30, ultra-low-power CMOS chip MSP430 and intelligent digital temperature sensor DS18B20. The thermometric node is powered with normal 3.6 V batteries where a double battery technique is applied, i.e. the operating circuit being power-on and the idle circuit being power-off to extend the operation life time of the node. The system can locate precisely spots exceeding the threshold temperature. The temperatures of all the nodes are collected every day to ensure normal working condition. For nodes with temperatures approaching the threshold, the system automatically reduces the time interval of temperature collection to avoid abnormal operation and damage. The system described in this paper has been successfully operated in Xi’qing Branch, Tianjin Electric Power Company for 1 year, proving the validity of this design.