Design Of The Three-phase Local Fees Charged Smart Watt-hour Meter

With the rapid development of electronic technology and communication technology, electrical equipment gradually has gradually realized the intelligent, digital and networking, which has laid the technical foundation for the development of the smart grid. Watt-hour meter should meet the higher requirements in function design and intelligentization with the development of smart grid, in addition to the basic measurement function, smart meter should realize automatic time-sharing measurement, prepaid, settlement, load monitoring, power management and the related control functions.Basing on the practical application of watt-hour meter, combined with the related watt-hour meter design requirements, this design develops a three-phase intelligent watt-hour meter, the main characteristic of this design is to be able to realize local topup, deduction and switch control function. Overall the process of design adopts the modular design concept and object-oriented design thought, the system design is decomposed into several sub-modules through the analysis of watt-hour meter system design requirements, firstly sub-modules are developed and tested, and then carries out the system debug and verification. In terms of the hardware design, this design uses CP3268 microcontroller device with ARMCortex-M3 kernel as MCU, uses ADE7878 as metering device, in addition, this design is mainly aimed at the CPU card module, ESAM module and relay control module, as well as the analyzing the process of data interaction between CPU card and ESAM module, adding the fault-tolerant approach when developing the relay control module circuit design; In the process of software design, using c plus language, points of the module design and development, through the abstraction of the module function, establishing corresponding model, this design achieves the target of reducing the coupling between modules, improving the development efficiency and maintainability of the system.Through the comprehensive debugging and testing for this design, verified the function and the performance of the watt-hour meter, this design of three-phase local fees charged with intelligent watt-hour meter has the advantages of precision in measurement, perfect functions, reliable performance, and meets its design requirements.