Design Of The On-line Monitoring System In Distribution Network

An on-line monitoring system in distribution network makes up of a complete automatic management system including real-time information, offline information, user information, network structural parameters and geographical information integration in distribution network by using modern electronic technology, communication technology, computer and network technology. It achieves monitoring, protection, control and distribution management under normal and accident condition of the power system.An on-line monitoring system is designed with circuit breakers, feeder terminal units and GPRS DTU on the purpose of feeder automation. This paper emphatically designs SCADA system based on the GPRS data communication, selects the GPRS and Internet communication mode and sets parameters of GPRS DTU, according to the practical running environment of the system. GPRS communication interface based on secondary development, serial communication interface and feeder terminal modules are developed in the form of dynamic link library achieving data transmission between communication interfaces and feeder terminal modules. SCADA system including the communication configuration system, the master control system and SQL Server2000 data management system achieves data acquisition, data storage and fault alarms, displaying status of circuit breakers in the form of cartoon and remote control of circuit breakers in power network.The system has been put into practical operation in distribution network. Analog variable and switching value are timely called, the fixed value of protection and the mode of protection can be remotely modified, the success rate of remote controls is 100%, and the response time of the failure is less than 1s, the correct rate of data packets is more than 99%, under normal operating circumstances.The on-line monitoring system in distribution network is described in this paper. It can monitor the run condition of power network in real time, and when failure or abnormal operation occur in distribution network, the on-line monitoring system has the issue of fault alarm signal , the estimation of fault type, rapid isolation of fault zone, timely current supply of non-fault zone. It can reduce outage time and outage area; improve the quality of electric energy and the utilization rate of equipment; optimize the operation mode of the distribution network; effectively guarantee the reliable operation of the distribution system, it can also improve the working efficiency and the economic benefits of the power company. It basically meets the requirements of feeder automation.