Abstract: Thermal characteristic is one of the important bases for fault detection and running of oil immersed transformer. It’s meaningful to detect abnormal operation timely by online monitoring system of temperature and temperature rise of transformer. The system based on DS18B20, uses MCU as slave computer, and high performance PC as host computer. It achieves to monitor the temperature and temperature rise in real time, and completes data displaying, curve drawing, alarming, report printing, fault recording and analysis. The results show that the system can shorten MTTR and prolong MTBF.

Key words: oil immersed transformer, thermal characteristic, DS18B20, MCU, GPRS