Relay Settings Calculation After A Large Capacity Power Source Is Connected To Regional Power Grid

Relay protection as an important part of power generation and transmission,is very important guarantee for the safe operation of power system,and plays an important role in the safe and stable operation of power system.Especially the current system voltage level is getting higher and higher,the capacity of power plant and substation becomes more and more big,any fault can cause serious accident or significant loss.Therefore,along with the development of the power system,there is higher and higher requirements for the relay protection,it is hoped that it can isolate fault quickly and selectively,at the same time,it cannot false trip.For a set of advanced relay protection system,it is able to play its full role and make sure the safe and stable operation of power grid only when there are reasonable protection configuration and setting calculation.This study takes the transmission and transformation project invested by the national grid in Africa as the research subject,and analyzes the protection configuration and the setting calculation principle of the relay protection after the large capacity power plant is connected to the power grid.First,the characteristics of the local power system are analyzed and studied,and with reference to the IEEE standard and the domestic power industry standards,this paper puts forward the protection configuration of the project.After that,doing the system modeling analysis,provide reference data for the risk assessment of the safety operation of all equipment,determining the system operation mode,and protection setting calculation.In the study of protection setting calculation principle,comparing the great differences between foreign relay protection and domestic relay protection,referring to the setting calculation guide of domestic power industry standard,and combining with the current situation of the local power grid,optimizing and improving the existing setting standard,the protection setting calculation principle which is applicable to the project is got through formula derivation and theoretical analysis closely.In this study,combining with the practical project,referring to international standards,from theory to practice,the settings of all relay protection of the whole project were completed,and they have been put into operation in the field,and run well.At the end of this paper,the contents of the work are summarized,and the next step of the work is prospected.