基于时序贝叶斯知识库的电网故障诊断软件原型系统设计

摘要

为了在故障后辅助调度员准确定位故障元件，揭示故障发展过程，文中利用时序信息设计了一种基于时序贝叶斯知识库(TBKB)电网故障诊断方法的原型系统。该诊断方法利用元件故障与保护动作、保护动作与相应断路器跳闸等之间的因果关系与时序关系，建立电网故障诊断模型，通过时序约束一致性检查方法，检查保护、断路器动作的时序。针对信息缺失情况进行状态假设，形成假设状态组合。通过贝叶斯推理，判断故障元件、误动与拒动的保护与断路器。根据此原理设计的原型系统，包括数据获取、TBKB 模型建立、故障诊断推理、分层因果图显示等模块，给出了TBKB诊断模型自动生成、诊断算法实现、分层因果图的构造与显示等关键技术的实现。该原型系统为电网故障诊断的工程应用提供了参考。%To assist the operators in detecting the fault component and identifying the fault developing process,a prototype system of power system fault diagnosis based on temporal Bayesian knowledge bases (TBKB) is studied. The causal relationship and temporal constraint relationship among the fault components and protection operations,protection operations and related breakers tripping are utilized to build TBKB models.The consistency checking is made to find the temporal rationality of the protections and breakers.For the information missing of states in the nodes,the state assumption is adopted to create hypothetical state combinations.Bayesian reasoning is made to detect the fault component and identify the mal-function and rej ection of protections and breakers.A prototype system based on the theory is designed,including the modules of data acquisition,TBKB diagnosis model development,fault diagnosis reasoning and layered cause-effect graph display.The key techniques are described,such as the automatic generation method of TBKB fault diagnosis models,implementation of diagnosis algorithm and building and display of layered cause-effect graph.The implementing of prototype system provides a reference for the engineering application of power system fault diagnosis.