基于CAN总线的煤矿企业电网接地故障选线系统设计

Design of Grounding Fault Line Selection System for the Power Grid in Coal Mining Industry Based on CAN Bus

煤矿企业电网一般为小电流接地系统,出线距离长且支路数目多,基于单片机或者数字信号处理器的小电流接地故障选线装置在应用中具有一定局限性。本文设计并开发了小电流接地故障选线系统,将原来选线装置中的数据采集模块和数据处理模块分开,并采用了具有自校准功能的高精度零序互感器,提高采集数据的准确性。该系统的核心是基于多通信端口并融合多种算法的故障选线平台,并通过通信网络与就地智能零序互感器、综自系统以及远程终端相互联系,实现了故障选线、故障录波、远程监控等功能。针对煤矿企业电网出线数量大、传输数据多等特点,此故障选线平台与就地智能零序互感器间采用控制器局域网络总线通信方式,并解决了不同安装处就地智能零序互感器的数据同步问题。实验测试表明该同步方法得到的数据可以满足故障选线算法对相位精度的要求,该故障选线系统可以较好地应用于煤矿行业小电流接地系统。

In general,the power grid in coal mining industry is a small current grounding system,which has a long line distance and a large number of branches. Therefore,the fault line selection device based on single chip or digital signal processing（DSP）has some limitations therein. In this paper,we designed a fault line selection system for a small cur？rent grounding system by separating the data collection module from the data processing module in the original line se？lection device and using a high-precision zero-sequence inductor with self-calibration function. In this way,the accura？cy of data collection was improved. The core of this system was the fault line selection platform,which was based on multiple communication ports and the integration of a variety of algorithms;it was also interconnected with local intelli？gent zero-sequence inductor,integrated system and remote terminal through the communication network,achieving functions such as fault line selection,fault recording and remote monitoring. Considering that the power grid in coal mine industry has a large number of outlets and a large volume of data transmission,we chose a controller area network （CAN）bus communication mode between the fault line selection platform and the local intelligent zero-sequence induc？tors. Moreover,we solved the data synchronization problem between local intelligent zero-sequence inductors in differ？ent places. Experiment results show that the data obtained using this synchronization method can meet the requirement for phase accuracy from the fault line selection algorithm,and this system can be applied to the small current grounding system in coal mining industry.