Wireless Sensor Network Positioning System For Intelligent Substation

With the development of computer technology,smart grid has become the mainstream development direction of modern power grid.As an integral core part of power grid,transformer substation undertakes the functions of power consumption and distribution.Its operation safety,reliability and economy are directly related to the operation performance of power grid.However,in the daily operation and maintenance of transformer substation,the location information of operators and equipment has become an important factor affecting the safe operation of transformer substation.Aiming at the problems of poor real-time and positioning blind area of operators and equipment positioning in transformer substation,this paper combines the advantages of wireless sensor networks(WSN)technology,such as high positioning accuracy,low power consumption and flexible construction mode,and constructs a WSN positioning system for intelligent transformer substation.The main research work of this paper is as follows:Firstly,an iterative positioning algorithm of reference point based on the density-based spatial clustering of applications with noise(DBSCAN)is proposed.Several node ranging methods,data preprocessing methods and node positioning methods are compared and analyzed.The DBSCAN algorithm is proposed to cluster and preprocess the RSSI signals,and the distance between the beacon node and the target node is calculated based on the accurate RSSI after clustering;Based on the distance,the coordinates of three reference points are calculated respectively,and their centroid is used as the initial coordinates of the target node.Then,the distance deviation factor is calculated to correct the distance between nodes and iterate the reference point coordinates,so as to update the positioning coordinates of the target node until the iteration criteria are met.Secondly,the overall hardware structure of intelligent transformer substation positioning system is constructed.The hardware of intelligent transformer substation positioning system includes three parts: data acquisition layer,network transmission layer and application display layer;The hardware circuit schematic diagrams of each module of beacon / target node and gateway node are designed and drawn respectively.The difference between gateway node and beacon / target node is that different main control chips are used and GPRS communication module is added;Completed the drawing,packaging,punching,welding and debugging of PCB.Thirdly,the software of intelligent transformer substation positioning system is constructed.The software of intelligent transformer substation positioning system includes four parts: RSSI data acquisition,RSSI data acquisition,RSSI ranging and target node positioning;Using the development tools such as IAR embedded workbench IDE and QT,the node coordinate solution program and upper computer software of the lower computer end of the intelligent transformer substation positioning system are developed.The upper computer software can realize the functions of the preset coordinates of the beacon node,the required coordinates of the target node,and the alarm of dangerous points.Fourthly,the simulation analysis and experimental verification of the positioning system are carried out.Matlab software is used to simulate the positioning algorithm proposed in this paper.The mean filtering algorithm and DBSCAN clustering algorithm are used to preprocess the RSSI signals under different node distances,and the trilateral centroid positioning algorithm,weighted centroid positioning algorithm and the positioning algorithm proposed in this paper are used to locate the target node,The comparative analysis shows that the positioning algorithm proposed in this paper has high positioning accuracy;For further verification,the indoor environment is selected for positioning experiment.The experimental results also show that the positioning algorithm proposed in this paper has high accuracy and can be applied to the intelligent transformer substation positioning system.Figure [56] Table [12] Reference [80]...