Research Of PMU's Measurement Data Transmission In The Smart Grids

As the global resources and environmental pressures continue increasing, the communiti's demand of energy saving, environmental protection and sustainable development is increasing too.At the same time the process of the electricity market continuing pushing forward and the user power supply reliability and quality requirements continuing improving , requires the future power grid must be able to provide a more secure, reliable, clean, quality electric power, so Smart Grid come into being.Smart Grid highly integrates the information technology, the communications technology, the measurement technology, the computer technology and the former transmission and distribution infrastructure, and forms a new type of grid.This paper particularly describes the measurement datas'transmission research status and the basic principles of the measurement techniques PMU device which is applicated in the Smart Grid, and researches the transmission of measurement data conducted in-depth, and finally concludes with a design.Communication technology is a very important part of Smart Grid, this paper optical fiber as the last physical media by comparing and studying the existing physical media;In order to meet the requirements of the real-time communication system, this paper analyses the existing 4 communication patterns, as the IP + SDH mode has a higher throughput, lower protocol overhead, and higher bandwidth utilization, network bandwidth which can ease the problem of the shortage of bandwidth resources, we select this model in the end.In the transport layer we use the connection-oriented TCP protocol, and in the application layer we use IEEE C37.118 protocol.In order to achieve reliable communication between PMU devices and servers, we apply Socket technology based on TCP/IP to complete the information exchange between the two.In order to reduce the transmission delay to the maximum possibility, the paper also developes a data compression software for the communications system, after the data compression performance testing of the PPM algorithm and the LZW algorithm, we apply the LZW algorithm finally, and we modify the length of the hush table in the LZW algorithm when the code realizes, by comparision we conclude that the improved algorithm is greatly improved in the compression time and compression ratio.