传统的微机继电保护系统通过设备双重化配置来提高可靠性,这种方案并没有充分利用变电站内的各种保护信息,且在一定程度上造成了投资浪费。文章以基于IEC61850标准以及电子式互感器的新型数字化变电站通信网络为基础,提出了解决保护装置失效和数字互感器失效的新型可靠性技术方案,分别是共享备用保护单元和软后备信号流切换;并依据IEC61850标准确立了两种方案的逻辑节点和逻辑结构。通过分析多播应用关联(multicast application association,MCAA)模型与双边应用关联(two party application association,TPAA)模型的优缺点,确立了逻辑节点间的关联模型,并选择面向通用对象的变电站事件(generic object oriented substation events,GOOSE)快速报文作为主要通信格式。通过OPNET网络仿真得到了两种可靠性方案的投切时间,证明了两种方案的可行性。
To improve the reliability of traditional microcomputer based protective relaying system the mode of double configuration is applied, however such a mode does not fully utilize various protective information within the substation and brings about the waste of investment to a certain extent. Based on the IEC 61850 standard and the communication network in new type of digital substation where electronic instrument transducers are adopted, two schemes to improve the reliability of protection devices are put forward, one of which is to build shared backup protection units (SBPU) to cope with the failure of protection devices inside substation and the another is to adopt software back-up (SB) scheme that does not add hardware but only change data flow direction while the data deletion happens due to the fault of electronic instrument transducers inside substation. According to IEC 61850 standard, the logical nodes and logical structure of the two schemes are determined. By means of analyzing the advantages and disadvantages of multicast- application-association (MCAA) model and two-party- application-association(TPAA) model, the association model among logical nodes is decided, and the general object oriented generic object oriented substation events (GOOSE) message is chosen as main communication format. Through OPNET network simulation, the switching on/off times for the two proposed reliability schemes are obtained and the feasibility of the two schemes is proved.