Study Of ZigBee Communication Network Reliability In Substation

In recent years, ZigBee technology is widely used in various fields. In the power industry, ZigBee technology applies to power generation, transmission, distribution, substation all aspects, provides a reliable technical support to smart grid construction. In temporary substation ground wire monitoring system, ZigBee technology enables real-time accurate transmission of ground wire state data. However, due to the quality of wireless signal susceptible to external environmental interference, it’s very important to do research on the reliability of ZigBee communication network.This paper firstly studied the mode of transmission and fading characteristics of wireless signals especially ZigBee signal, and then analyzed the electromagnetic interference in substation and its impact on ZigBee signal. Taking into account the complexity of substation environment and instability of wireless signal, existing models can not estimate the signal strength fading in substation environment accurately. A substation environment path loss model is needed. This paper analyzed and compared the common path loss models, and selected to do parameter modification on the basis of logarithmic path loss model.This paper designed and implemented a temporary ground wire monitoring system, completed the function formulation and construction design. Introduced the system works and functions of each part in detail, described the chip model of each module, hardware and communication interfaces, and drew a flow chart of the system software. This paper took the system as a test object, tested ZigBee received signal strength at 10 kV, 35 kV, 110 kV, 220 kV four voltage levels outdoor substations, analyzed the statistical results of the experimental data, fitted the data by least squares method in matlab, and then took fit parameters into logarithmic path loss model to optimize, finally got the ZigBee signal path loss model in line with different voltages substation environment.Path loss model can accurately estimate the coverage of the nodes, but to choose a reliable routing node, the communication quality of the link is needed. This paper analyzed and compared link quality evaluation parameters and current evaluation algorithms, proposed an evaluation algorithm based on path loss model against their shortcomings, to get a more accurate assessment of the communication quality of current link, and provide reliable support for the choose of routing node. In addition, this paper studied the reliability of ZigBee communication network node, data transmission reliability, network structure reliability, put forward corresponding solutions for different problems, comprehensively improved the reliability of ZigBee communication network.