Study On Relay Protection Setting System Of Distribution Network

As an important part of power grid,the safe and reliable operation of distribution network is directly related to the safety of power supply to users and power quality.The relay protection device in the distribution network is the barrier for the safety of the operation equipment of the distribution network.Its correct and reliable action plays an important role.The failure or misoperation of the protection will seriously threaten the safe operation of the distribution network.With the increase of distribution network scale and hierarchy,the difficulty of operation and management increases,which makes the setting complexity of distribution network relay protection increase greatly.At the same time,with the increase of the permeability of distributed generation(DG)in distribution network,the traditional setting software of distribution network can no longer meet the requirements of modern distribution network.Therefore,it is of great significance to research and develop a new,open and flexible setting calculation software.In this paper,the protection configuration of medium and high voltage distribution network is summarized.Based on the requirement analysis of the setting system,the platform architecture and function of each functional component of the system are given,and the fault calculation component and setting calculation component in the system are mainly analyzed.The unified modeling language(UML)is used to model the setting system.Considering the characteristics of radial distribution network,on the basis of port compensation method,through the research on the fault characteristics of two types of distributed generation,unit type and inverter type,combined with the power flow calculation method of distribution network with DG,a fault calculation method for distribution network with distributed generation is proposed,and the specific process and steps of the method are given.On this basis,the object model and dynamic model of the fault calculation component are designed,and the fault calculation program is compiled with C + +,and the correctness of the designed fault calculation component is verified by an actual example.According to the distribution network protection configuration,the setting method is summarized.Considering the deficiency of CIM model to describe the protection equipment,the CIM protection package is extended and the protection method is extended.Combinedwith the setting idea of partition protection,the setting calculation component is designed by UML and object-oriented technology,and the setting calculation program is compiled by C ++ language.Finally,the actual distribution system is used to verify the designed relay protection setting system.The results show that the system has good performance and accurate calculation results.