Application Of Electrical Monitoring Technology In Low Voltage Power Supply System Of Metro

Chengdu Metro is the city transit system of Chengdu city in Sichuan province Chinese.the opening of the subway project exposed differential switch,low voltage cable voltage loss and cable channel congestion,cable connection loosening caused by fire hazards and many other problems.Because of the large capacity,large number and wide distribution of electrical equipment in the subway station,the low voltage power supply system is more complex,which has great influence on the operation efficiency of the subway line.How to correctly operate,maintain and repair,to ensure that the equipment is always in good condition,is an important link to ensure the operation of the subway.Therefore,the timely detection,troubleshooting,and take targeted improvement measures to ensure the safety,stability and reliability of the subway,the necessary methods.The low voltage equipment contact temperature monitoring system is composed of lower computer and upper computer.The slave computer adopts AT89C51 as the main control chip,and a plurality of temperature sensor DS18B20 is connected to the single chip through a single bus structure.Through the temperature of the DS18B20 collection,the data collected through the AT89C51 processing by the LCD to carry out the temperature value of the display.System can be set separately each DS18B20 alarm threshold,when the acquisition data exceeds the set threshold,response to a buzzer,also the DS18B20 which is corresponding to the LED lights will often bright to alert staff alarm location.The upper computer of the system is realized by Lab VIEW,the design of the host computer can achieve the goal of remote temperature monitoring.The temperature of each point is displayed by the temperature value frame.In addition,the temperature of the different contact points can be set,and the indicator light of different colors is marked.The components used in the system and the design process to achieve the goal of low cost,high precision and easy to expand,can meet the conditions for large-scale promotion and use.On the basis of general PC function,combined with the actual needs of the expansion and improvement of the further development of temperature measurement system has a certain reference value.