Design And Develop For Centralized Meter Reading Based On Carrier Communication Over Power Line

Centralized Meter Reading System refers to an intelligent management system which can record the users’consumption of electric energy without power employees presenting. The traditional manual meter reading method has some deficiencies such as heavy work load, low work efficiency, which greatly influences the image of power enterprise. However, low-tension network has many superiorities,such as wide coverage, convenient joins, especially it can communicate without any additional lines, economizing much manpower, material and financial resources. Proposed in the present thesis, the centralized meter reading device of power carrier employs power lines as the primary communication channels, and reads the data of electric energy meters by power carrier or RS485. After the collected data are processed by CPU and measurement modules, they are transfered to the master station through Ethernet or3G network signals.In the thesis, firstly the background, source and significance of this research are introduced, meanwhile the development and current situations of centralized meter reading devices of power carrier at home and abroad are described. Then the overall design of centralized meter reading devices of power carrier is analyzed, and the communication technology of spread spectrum of power carrier, the digital modulation system, the choice of carrier chips and their technical indexes are introduced in the paper. Each module unit of hardware circuit, which is designed based on its functional requirements, is presented in the thesis. Concentrator hardware includes a power module, control module, metering module and communication module. The power module adopts CPU, carrier module,3G module and so on to supply power respectively in order to enhance its anti-interference capability. The chip of CPU is AT91SAM9260produced by Atmel, and the design of its peripheral circuit is introduced in detail in this paper. The chip of carrier communication module is TCS081C produced by Dingxin in Qingdao, and it is a communication chip based on direct sequence spread spectrum, whose modulation mode is frequency shift keying (FSK). The chip71M6515is used in metering module whose measurement data are regarded as the reference standard but not as a basis for charging. The chip of3G communication module is MU203produced by Huawei. and it communicate with the master station through the network of Unicom WCDMA. The software development environment of concentrator employs embedded real-time operating system LINUX which designs the Boot Loader and the driver Linux. It is worth mentioning that all the application layer software functions and their flow charts are presented in the thesis. Finally, according to the requirements of the power sector, the author tests and analyzes the centralized meter reading device in its power dissipation, lightning surges, static and group pulse interference and high-low temperature.The test results show that the reading efficiency and anti-interference ability of the centralized meter reading device both reach the relevant standards in power sector. After the centralized meter reading devices undergo trial erection and operation in a few cities, their operation results indicate that they possess stable performance and good reliability.