Software Design Of Real-Time Online Temperature Monitoring System In Substation High-Voltage Switchgear

With Chinese rapid economic growth, electricity demand increases day by day. The sustained rapid growth of electricity supply has brought a series of security problems to the power grid equipment. Power equipment mainly concentrates on substation. Switchgear, as the major power equipment in substation, is responsible for closing and disconnecting power line and protecting the security of the system. Switchgear plays an important role in the safe and reliable operation of substation. In recent years, several accidents have occurred in power plant and substation because of switchgear contact overheating, and caused fires and large-scale power outage. So the key to prevent such accidents is to solve the problem of switchgear contact overheating. However, because the environment where the high-voltage switch contact exists is high voltage, heavy current, strong magnetic field and strong electromagnetic interference, it is difficult to measure temperature manually and can not use the conventional temperature measurement methods. The development of fiber grating sensor offers the possibility of temperature monitoring in high voltage switchgear. Therefore, it is imperative to establish a comprehensive real-time online temperature monitoring system.This subject comes from the Rizhao Wulian Xiangyang substation real-time online temperature monitoring system project. We design and develop a new real-time online temperature monitoring system based on fiber grating sensor after we analyze the current situation of temperature monitoring in substation and the system requirements. The system works as follows:The data acquisition module will collect the measurements and save them to the MySQL database. And the on-site monitoring system first obtains the data from the database, and then handles data, such as real-time display, alarm and history search. Besides, it sends real-time temperature and alarm to the remote control room and checks time remote following CDT protocol. It meets the real time and reliability of the substation and the dispatcher center. So this system can really monitor temperature real time and online.The design of database is the basis and emphasis of the system. The frequent insertion and query operations bring serious challenges on the reliability and real time of the database so that the whole system may work badly. So we choose MySQL database. First, we design the database structure, and analyze the performance optimization of MySQL database so that the database can reach its high performance.This paper describes the software design in detail, including the build of the software and the design and implementation of various functional modules. We use Netbeans to develop a good human-computer interface, including real-time refresh of the measuring point module, the user management configuration module, real-time table, real-time curve, historical list, historical curve, report printing module, alarm module, and CDT communication module. This system is suitable for the unattended substation temperature monitoring.At present, the system has been put into use and works well. This system can monitor temperature changes online and real time, and predict the temperature trend. So the accident can be nipped in the bud. It is significant to ensure the safe and reliable operation of the equipment.