Regional Differential Protection And Standby Power Supply Applied Research In Dense Areas

In recent years,with the development of Chinese economy,the demand for electricity is more and more vigorous.The traditional power network protection control system uses a decentralized,relatively independent way,which has a certain impact on the performance.Under the complex grid structure,the control mode of the distribution system is complex,and there are many problems,such as the long line path in a certain 35 kV power network,the more T-connected substations,the more multi-level series of power supply,and the wide distribution of small hydropower.The complex network structure protection often occurs spanning action,which will affect the success rate of reclosing and standby self-injection in 110 kV substation,and reduce the reliability of power supply.The research background of power grid protection system and the current situation of domestic and international research on power network protection system,corresponding to the needs of Luquan County power grid,rely on the existing communication platform of Luquan County.The regional differential protection is used to realize the cooperation of different layers of equipment in the power network protection range,and the passive ray network technology is used to realize the synchronous sampling of regional data and the real-time transmission of a large amount of data,and the system of regional differential protection and reserve investment is established.Regional differential protection is used to realize the mutual cooperation of different layers of equipment in the power network protection range.The optimized setting ensures fast and reliable troubleshooting of the system;at the same time,based on different levels of information sharing,the station can operate on its own InvestmentThis project is based on the existing communication platform of Luquan County,combining with the characteristics of small power concentrated area,using passive ray network technology to realize the real-time transmission of regional data synchronously with a large number of data,and establishing a set of regional differential protection and backup system.The basic principle of differential protection is to calculate the difference between the currents flowing in and out of the protected area at the same time.When the difference is greater than the threshold value,the protection will work.Optical fiber differential protection is a kind of differential protection using optical fiber as communication equipment on both sidesof the line.Backup power automatic input device(BZT)is mainly used for backup transformer,standby line and backup power supply in power plant substation.In this item Based on the EPON communication technology,the control host can easily obtain all the real-time and synchronous analog information in the reserve.Using EPON technology to realize the real-time transmission of regional data synchronously with a large number of data,the system of regional differential protection and standby automatic switching is established,and the whole structure is intended to adopt “dual control mainframe distribution terminal”.The whole system is assisted by intelligent protection control host(APCU-2000)and intelligent acquisition and control terminal(APCU-1000)connected by passive optical network.The regional differential protection and backup system based on the real time information of the region,with the differential protection as the main protection and the backup protection as the main protection,can locate the fault location quickly and accurately,and satisfy the speediness and selectivity.The implementation of the project can solve the problems of complex setting of power network,difficulty of protection and coordination,influence of small hydropower on coincidence and backup,etc.At the same time,the system can simplify the operation and maintenance of equipment,and provide a system platform based on real-time information of the whole area.Convenient later function expansion.With the development of computer technology and large-scale communication technology,the information resources used in substation relay protection and control system have changed greatly.This article uses the current Innovation to improve and enhance traditional self-investment performance opportunities and conditions.Use this system to show outstanding performance,will certainly get good promotion in the future.The system has been put into use in some parts of Kunming at present,and it has a good response,because of its flexible and reliable characteristics,it brings convenience to small power dense area and is worth popularizing.The application of the proposed area differential protection and backup system in some small electrically dense areas shows that the research results in this paper have some practical engineering significance.