Research On Application And Security Of Wireless Sensor Network In Smart Grid Monitoring

Wireless sensor networks (WSN) consists of a large number of micro or small sensor nodes deployed in the monitoring area with a multi-hop self-organizing network formed by wireless communications. In recent years, with the development of sensing and communication technology, WSN is not only used in the military, construction and other large projects, but also in general life of people. And more and more people focus on its application in modern power grid.Modern power grid, also smart grid, is the evolution trend of the modern power grid because it can provide automatic control and improve power efficiency, reliability and sustainability of the power grid. It enables quickly and accurately detection when and where the failure happens, and notify the service provider. Smart grid can achieve interaction with users for allowing users to enjoy the benefits and easing the supply pressure at the same time. Smart grid also optimizes power structure and reduces environmental pollution by allowing renewable energy access to the power grid.It can achieve these functions depending on the advanced information and sensor technology. By the feedback information from the mass sensors, the power grid can react quickly under different circumstances and provide more comprehensive information to the users. However, the types of monitoring data are various and the amount is huge, so the traditional sensor networks cannot fully meet its flexible requirements. Therefore, by the sub-monitoring network established in the smart grid using WSN, the data of various types sensors dispersed in the area is integrated. Then the gateway node sends the data of the entire region to the backbone monitoring network. It can effectively extend the range of the sensor to monitor and meet the needs of the smart grid using this way.Now, WSN often works in smart grid for smart meters and advanced metering infrastructure (AMI) or transmission line monitoring network. In this thesis, our research is focused on applications of WSN in the smart grid transmission line monitoring. One contribution of our research is to propose a cluster based two hierarchical model of WSN to meet the demand of smart grid for end-to-end delay and reliability. And we also provide two communication schemes for sensors in one cluster and a cluster to the other one. We explore the most efficient data transmitting power scheme and verify the feasibility and accuracy of both communication schemes and the most efficient data transmitting power scheme by simulations of energy consumption and end-to-end delay. Another contribution in this thesis is providing two security protocols which are based on symmetric encryption algorithms and asymmetric encryption algorithms respectively according to the security requirements of communication networks in smart grid. Both protocols contain authentication and initialization of a new node, data encryption and authentication in uplink, distribution and authentication of control command in downlink, ensuring communication by self-healing process when malfunctioning nodes occurs and so on. In the last, we analyze the characteristics of two security protocols and validate the feasibility of self-healing process at the same time.