Research And Application Of Open Communication Systems In Power Systems DC Power Supply

In the digital substation, the DC power supply plays an important role in the power system. It supplies the control load, power load and emergency lighting for substation. With the establishment of intelligent transformation for centralized control station in110kV,220kV substation, and the design of digital substation in accordance with the latest standard in these over330kV substations, the DC power supply routine inspection and maintenance has changed.The traditional manual inspection is difficult to find the real time system failure, and because of the data measurement and repair personnel differences in artificial repair, it is not able to make accurate judgment on the actual system situation.The application of advanced computer technology is an important development direction and the key technology of power system, the dispersed DC power supply information have been obtained by real-time detection, online collection, automatic diagnosis and analysis, not manual inspection. As the communication standard, the IEC61850main objective is to achieve interoperability in substation IED (intelligent electronic devices).The paper has presented a design and implementation of open communication system foe DC power supply, in which the intelligent protocol conversion unit (communication manage) has been applied to achieve the IEC61850standard in DC power system, and the interoperability between DC power supply and IED. Data acquisition terminal search DC power support Modbus RTU protocol,and the collected data is converted into IEC61850protocol,then the communication management machine as the IEC61850server transmits the data to the host computer for data monitoring.All kinds of DC power supply information, acquainted through RS-485bus, has been sent to the communication management machine in binary stream, and communication management machine receives, analyzes, classifies and stores these data according to the formulated IEC61850Communication Protocol. The host computer remotely accesses the communication management machine through the network. The running states of DC power supply have been monitored, through analyzing the collected data, so as to problem can be found and maintenance be carried out in time. The paper has researched on the unified modeling to different DC power supplies, and the experiment has been made for the designed hardware system and client software. The results show that, the DC power supply has achieved open communication requirement. The communication system can real-time monitor the voltage, current, resistance, temperature, charge and discharge time of DC power supply, and it ensure the substation safe operating.