Feederautomation Based On The Area- Protection Of Principle

Feeder automation(FA)plays an important role in improving the reliability of power systems . The existing techniques are intelligent switches based FA and computer communication network based FA,The former needs the switches to reclose several times,thus it impulses the power equipments seriously.The latter needs transmitting fault information to main station,which telecontrols the corresponding switches to isolate fault sections after determination,therefore the restoration procedure lasts a long time and it depends on the reliability of so many elements as well.A new scheme of area-protection based FA is proposed in this paper.Each Feeder Terminal Unit(FTU)enduring a fault current sends a lock order to its up-stream FTU and a trip order to its down-stream FTU.respectively.The decision is made by each FTU according to its overload information and the message from its adjacent FTUs to isolate a fault within the smallest range and to avoid over-tripping.The FTU on loop switches decide whether to close the corresponding loop switches for restoration on the basis of no-voltage detection,settings of delay time and the message from the adjacent FTUs.The system could be done quickly to avoid a number of reclosing the impact of electrical equipment, fault information does not need to be uploaded to the main center of distribution automation and control decision-making stations, reducing the sound section of the fault diagnosis and recovery Power of time.According to the Area-Protection of the requirements of the design features of the feeder terminal unit, discusses the basic principles of troubleshooting, with a branch distribution network fault treatment and automatic re-closing process.The area-protection function is realized by C language on the platform of FTUs based on TMS320F2812 microprocessor.By laboratory simulation experiments on the surface feeder protection system automated functional testing, test results show that the design is feasible.