Design And Implementation Of Distribution Network Fault Location System Based On WSN

Distribution network is the last link of power production and operation directly with users,and its reliability is the direct embodiment of the operation and service capability of electric power enterprises.According to statistics,more than 95% of the power failures suffered by power users happen in the distribution network,so the current distribution network transformation and distribution automation construction has become a hot topic in the power industry.The existing distribution automation system focuses on the realization of relay protection and switch division and control,and the data of remote real-time measurement are too few,so that the rapid positioning and isolation recovery processing methods after failure occur are limited.Therefore,the research of wireless sensor network(WSN)application in fault location of distribution network,enrich the existing distribution automation system function,to improve the economic operation efficiency,reduce the average outage time of distribution network and distribution network system average interruption frequency,enhancement have important significance and value of other reliability indexes.Fault location online first need to obtain accurate information of the distribution network,the characteristics of distribution line based on the research and design of a wireless sensor network,the sensor is installed in the distribution line to complete the acquisition and pretreatment of voltage and current information,and the recovery of data set,through the wireless communication network information sent to the monitoring center,the data were analyzed and processed by the monitoring center.All kinds of existing fault line selection and location algorithm can be implemented in the background software,which is conducive to the safety and reliability of the distribution network and economic operation.There are two kinds of grounding modes in China's distribution network: neutral point ungrounded and arc suppression coil grounding,which is a non effective grounding mode,that is,small current grounding system.Firstly,the characteristics of two grounding modes after single-phase grounding fault are analyzed.Then,according to the fault characteristics,we get the location criterion phase method and the location criterion of neutral grounding system--zero sequence current increment method.The proposed phase criterion is not affected by the transition resistance and so on.The error allowed range is large,the reliability is high,and it has high practicability.Because the nodes are affected by various bad environment conditions in the actual operation,the data will be distorted in data transmission.According to the distortion data of the monitoring center,this paper presents an improved differential evolution algorithm for fault location in distribution network,and to verify the algorithm.The results show that the algorithm not only has the advantages of simple operation,good global search capability,easy programming and fast convergence speed,high reliability.On the basis of the above work,a wireless sensor network is designed,including hardware design and software design,and as much as possible to be economical and practical.The main part is the design of the coordinator node and sensor node,so that it can synchronously collect and transmit the data we want.Finally,an experiment is carried out in the 10 kV distribution network.The location result is the same as the actual inspection result,which indicates that the positioning system designed in this paper has high accuracy and practicability.