The Design Of Polyphase Smart Electricity Meter Based On DLMS/COSEM Protocol

The three phase energy meter have a lot of problems which found in the use of the meters, meter manufacturers and meter types which has caused the difference of respective communication protocols. In order to solve these problems, it is much needed to design a kind of smart three phase energy meter with uniform communication protocol and full functions to meet the need of the current market.Nowadays DLMS/COSEM communication protocol has been used world widely; the protocol adopts uniform way to realize the data exchange between meters and meter reading equipments, so the restriction of country, manufacturer, meter type and communication medium no longer exists, and the problems of uniform management and compatibility and other problems are solved. The purpose of this article is to discuss how to design a new type smart three phase energy meter in accordance with DLMS/COSEM protocol.Firstly the article puts its emphasis on the explanation of DLMS/COSM protocol; the article will discuss separately the main system of international standard 62056, including communication structure (or the physical layer), data link layer, application layer, communication port and object symbolizing system.Secondly the article will explain the main function and working principle of the smart three phase energy meter in the perspective of hardware. After full consideration of the performance and function to confirm the designing solution: adopting UPD78F1166 of NEC and ADE7878 of measuring chip as basic platform, plus power, real time clock, communication port, data memorizing circuit and ambient circuit.Then introduce the communication part of software design on the established hardware platform, the article will explain how to realize the communication function by DLMS/COSEM protocol through the software. Besides, the article will introduce using modularizing software design to realize the function of energy measurement, demand measurement, display, and events recording.According the above research, we can successfully design the smart three phase meter based on DLMS/COSEM protocol to realize communication function. The meter can not only meet the need of accurately measuring energy, but also realize the full function of energy meter; more important, we can push ahead to the international market with the international communication protocol.