一种改进的电网故障诊断优化模型

An Improved Model for Optimizing Power System Fault Diagnosis

电网故障诊断优化模型可将诊断问题表示成求极值的0-1整数规划问题,从而可通过严密的数学运算来确知故障设备。文中在对目前故障诊断优化模型深入研究的基础上,分析其存在的不足,尤其是对诊断结果不唯一、且某些结果不合理的问题进行了剖析。发现其诊断结果不唯一的原因在于该模型仅考虑了保护各自状态的影响,而忽略了主、后备保护之间状态关系对目标函数的共同影响;在此基础上,综合考虑目前二次系统配置特点以及诊断信息特征,提出了一种改进的电网故障诊断优化模型,在新模型中充分考虑了断路器失灵保护的特殊性,并对各设备的期望状态函数进行了重新定义。文中还对诊断故障原始数据预处理和系统实现进行了简单描述。理论分析以及大量的实例验证表明新模型更加合理,诊断结果更为准确。

A model for optimizing fault diagnosis for power systems is formulated as a 0-1 integer programming problem. The fault equipment can be determined by means of refined mathematical manipulation. Currently used optimizing models and their disadvantages are thoroughly studied, especially the problems of irrationality and non-uniqueness of some diagnosis results. It has been found that the cause of the non-uniqueness lies in the fact that the model only takes the influence of each protection into account to the neglect of the joint influence between the main and back- up protections. On the basis of this finding and taking an overall view of the configuration characteristics of the currently used secondary systems and the features of the diagnosis information, an improved optimizing model of fault diagnosis for power systems is proposed. The particularity of the breaker malfunction protection is considered in the new model. The expected status functions of equipment are redefined. The preprocessing of the raw data on fault diagnosis and the realization of the system are also briefly discussed. Theoretical analysis and example verification indicate that the new model proposed is more rational and the diagnosis result more accurate.