Protective Relay Automatic Designing Of The Distribution Network Of A City

With the rapid development of A city social economy,the distribution network scale has been expanding.Shortage of space resources and power supply capacity of distribution network is increasingly prominent and gradually become an important factor restricting the development of the local.Because of some historical problems,such as the relationship of power grid management and the development and construction of power grid,the regional distribution network has been constructed without unified planning,and the construction and transformation has not been valued.Owing to inefficient management of some sub areas,the distribution network is becoming scattered and mutual supplying capacity is missing.At the same time,the power quality problems caused by the aging of some network lines,backward equipment performance and the lack of related technologies have seriously affected the local construction and residents' lives.Building a distribution network which is coordinated with the urban operation and development and maximally meets the user needs for the electric energy is the urgent problem to be solved by the local power supply company.In this paper,taking A city as an example,the relay protection automation of the 10 k V distribution network is upgraded to ensure the safety operation of the power grid to reduce power loss and improve the reliability of power supply upgrading.Firstly,this paper emphatically discusses 10 k V and below distribution network structure,connection mode,operation mode and interactive capacity,load structure and other related content.This paper analyzes the causes of common faults of distribution network in the area,and then points out the main problems existing in the distribution network.On the basis of the above,the aim and idea of the upgrading design of relay protection automation of distribution network are put forward.Meanwhile,combined with representative line conditions and operation and maintenance requirements,something are proposed including the subsection equipment selection principle,lines and equipment modification principles,communication system upgrade and protection setting calculation principles.The implementation scheme and the extended application of the typical line are given in detail.Finally,the economic and social benefits of the reconstruction project are analyzed.Analysis shows that upgrading design scheme of relay protection automation of distribution network in this area is reasonable and feasible.The scheme can improve the power supply reliability and power quality and meet the growing demand of users for electric power.Besides,it has important guiding significance to the construction of urban distribution network in future.