Small Current Grounding System Feeder Switch For Single-phase Grounding Protection

It is always the focus of research in the field of relay protection that small currentgrounding system feeder switch single-phase grounding protection. This paper put aemphasis on the protection of small current grounding feeder system of distributionnetwork switch for single-phase grounding.It has do some research on the feederswitch for single-phase grounding protection and the same feeder fault sectionlocation comprehensively and systematically with the integration of theoreticalanalysis and intelligent algorithm principle. This research will promote the continuouspower supply reliability of distribution network automation level.It discussed the distribution and correlation characteristicsof feeder three-phase zero sequence current theoretically based on the steady-state andtransient process and formation mechanism of the small current groundingsystem fault. Each deficiency of the zero sequence active power and the first halfwave method was found through simulation. Further more, the zero sequencecompensating admittance method was put forward to fill in the malfunction region ofthe complex plane in action admittance based on zero sequence admittancemethod. This method can bear strong transition resistance, and it had just a little effectof the distribution network structure of the system and the neutral point groundingmode, and it had higher reliability by simulation. The above three methods candistinguish different feeder fault to some extent, but it requires additional time delayswitch for the same feeder different fault interval, which will prolong the action timeof feeder switch.The purpose of this paper is to shorten the time of feeder switch and removedelay switch. So it deeply researched the fault section and matrix algorithm and theimproved one on the basis of single-phase grounding protection principle. But thismethod had great fault tolerant. By analyzing the principle of ant colonyalgorithm, ant colony algorithm was creatively introduced to the fault sectionlocation to solve the fault interval artificial ant colony algorithm of algebraicthinking and artificial bee colony algorithm based on geometric ideas by simulationand it had high convergence, less iteration times, and can quickly determine accuratecalculation of fault interval.