Research On Application Of Wireless Sensor Networks In Smart Power Grids

Wireless sensor network (WSN) is the cutting-edge research focus in the current field of information technology. It has great scientific significance and broad application prospects. With the development of manufacturing processes and further research related to communication protocols, it takes an increasingly important role in the power system.Smart grids are a relatively complex integrated system. One of the main characters is high security that appears in many ways, such as power equipment safety, power transmission equipment safety, data transmission security and so on. The security discussed in this paper focuses on two aspects:rapid and accurate localization of transmission line fault and data transmission security. Based on former work, the author presents localization mechanism named DV_Same_Hop, which will improve the traditional location algorithm by installing the sensor in the transmission line based on its actual characteristics. The new localization method can meet the requirements, such as robustness, self-organization, energy efficiency and so on. Further more, this methord is simple and feasible, the experiments show that it is an ideal transmission line monitoring program. Depending on the way of data transmission, the smart grids include cable and wireless networks, the wireless networks mainly refer to wireless sensor networks. Accordingly the data transmission security, smart grids involves the security of cable transmission and wireless sensor networks. The cable networks have a long history, their security mechanism and technology are very mature. However wireless sensor networks are application-specific networks, they are still new and hot in field of research. Digital watermarking technology which can solve the security of sensor networks data transmission in the smart grids, the author present watermarking algorithm solving the sensor networks security which considers respective characteristics of smart grids and sensor networks, generates the watermarking information by using of the constantly changing characteristics of alternating current, because of the energy limitation of sensor network nodes, fully considering the low complexity of the algorithm and taking advantage of simulation data of the experiment, this paper illustrates the rationality of watermarking algorithm. The author's work consists of the following two points:(1) DV-Hop location algorithm is based on range information, the hop value is estimated by doing the multi-hop distance on the average. Therefore the error is larger and the localization is rough, based on the characteristics of transmission line, the hop model is designed to arrange the sensor nodes, and then calculate the physical distance of hop. The author analyzes the shortcoming of location of trilateral calculation, calculating the coordinates of unknown nodes by hyperbolic positioning mode, using the Chan algorithm to solve the problem. Finally, the author analysises the improved algorithim's performance by simulating.(2) The author further studies the characteristics of wireless sensor network transmission to solve the data security issues of wireless sensor network in smart grids, presents the watermarking generation,embedding and checking algorithm based on alternating current, and proves its validity and feasibility of the algorithm by simulation experiment.The author's work is supported by following projects:Power Transmission Equipment & System Security and New Technology issues of State Key Laboratory (No.2007DA10512710407), Doctoral Fund of Ministry of Education (No. 200804971030) and Special Fund of Scientific Research of Central Colleges (No. 2010-Ia-049).