Application Research On Integration Of Secondary Devices In The Intelligent Substation

With the rapid development of intelligent substation,the secondary integrated equipments,as the important part of smart substation,are widely used.However,the application effectiveness of secondary integrated device is quite concerned by the industry.This paper studies the application of integrated secondary devices in smart substations and analyzes its application efficiency.Based on the project of a 110 k V intelligent substation in Yichang,from the angle of reliability and economic efficiency of secondary equipment selection,these three application cases of the selection of integrated equipment,non-integrated equipment only,and two kinds of equipment are compared and analyzed.The main works of this paper are as follows:First,the principle and technology of major integrated secondary devices in smart substations are analyzed,such as integrated device of merging unit and intelligent terminal,integrated device of protection and control device,integrated device of fault recording and network message analysis device,etc.According to the principle of each device and the information flow of the secondary system of the intelligent substation,the possibility and implementation method of integrated secondary devices are analyzed.Then,from the point of view of reliability and economy,the feasibility of the integration of secondary equipments in Smart Substation is analyzed.The two methods of the fault tree method based on HAZOP and the reliability block diagram method are used to analyze the reliability of each equipment and its components.The economic analysis of the application of the secondary equipment is made by the whole life cycle cost method.Finally,taking an example of a 110 k V intelligent substation in Yichang,the scheme selection of the secondary equipment integration and the configuration numbers of the integrated secondary equipments are analyzed.Through reliability analysis,the availability of the integrated secondary equipments and its components is higher than that of the non integrated equipment and the system composed of them.The cost of the secondary equipment is divided into input cost,operating costs,maintenance cost and discard cost.The corresponding calculation method is selected according to the type of cost.The total life cycle cost of the equipments is calculated based on the specific engineering and the quantity of equipments.Through cost comparative analysis,it is validated that the application of integrated secondary equipment has economic advantages over non-integrated equipment.From this,it can be concluded that the application of integrated secondary equipments in smart substation has obvious advantages over the non-integrated equipment.