Detection And Evaluation Of Substation's Secondary Circuit System Statement

With the continuous expansion of the scale of modern power system,especially the development of Smart Substation Technology.Traditional maintenance mode of relay protection has been unable to meet the requirements of safe and stable operation of power grid.The experience of power grid accident shows that the defect of secondary system is one of the important causes of relay protection system accident.Because of the complexity of secondary system of relay protection,it is difficult to carry out long-term effective state detection.For the two profession,state detection and evaluation technology becomes particularly important.This paper first puts forward the method that the substation two system is divided into state detection and evaluation.This paper introduces the basic concepts,characteristics and objectives of state detection,and analyzes the operation mechanism of intelligent substation in detail,including the components of intelligent substation,the coordination relationship between various devices,operation process and the role of configuration files in operation.In view of the conventional substation secondary system,this paper puts forward the idea and method of on-line detection of AC secondary circuit,secondary circuit,secondary operation circuit and outlet contact of tripping and closing.An on-line monitoring method for intelligent substation is proposed,which mainly includes two aspects: one is the fault information monitoring of equipment itself,including merging unit,intelligent terminal and protection device;the other is the on-line monitoring of secondary circuit in intelligent substation,including communication status monitoring of physical link and logical data link.State monitoring.Finally,this paper presents an evaluation method based on fuzzy theory to model the substation secondary system,assigns weights to important links with the help of expert experience,uses fuzzy analytic hierarchy process combined with the evaluation results of 66 k V Wanghe substation in Liaoning area to carry out numerical calculation,and finally obtains the comprehensive evaluation score,through a practical case.The important role and practical significance of the evaluation method in running state detection are demonstrated.