Design And Implementation Of Network Three-phase Multi-function Meter

With the rapid development of the national economy,electric energy has become an indispensable development energy,and electric meters have received extensive attention as important equipment of the power grid.In response to the current demand for smart grids,China’s State Grid Corporation has proposed the corresponding application direction of IoT technology.Therefore,combined with the current development trend,this thesis researches and designs a multi-function electric meter with IoT communication function.The current research status of multi-function meter and remote monitoring system are introduced in this thesis,and the technology of Internet of Things is analyzed.Based on the analysis of several design schemes of multi-function meter,the Internet of Things technology is applied to the design of multi-function meter.The overall design and debugging of software and hardware are carried out.The system mainly includes multi-function meter and remote monitoring center.The MSP430F149 ultra-low power control chip is used as the monitoring core of the multi-function meter.The peripheral circuit is designed and built,and DS1302 is used as the real-time clock.DS18B20 is used to detect the temperature of electric meter.The ATT7022 high precision power measurement chip is used to realize the accurate measurement of power parameters.The multi-function meter includes key circuit,realtime clock circuit,communication circuit,anti-stealing circuit,temperature circuit,relay driving circuit,LCD 1602 display circuit etc.The Flash storage inside MSP430F149 is used to realize power-off storage of parameters.The system software design applied the classical front and back-end structure.The measurement and data upload of power parameters such as power and power factor are realized.The operation of power supply and power off can be realized through the relay actuator.The harmonic analysis of voltage and current can be achieved based on the interpolation windowed FFT algorithm.The remote monitoring center of the system is built based on the cloud platform of smart cloud and Internet of Things equipment.The multi-function meter is connected with the cloud platform of Internet of Things through ESP8266 WIFI module to realize the remote monitoring of it.The function of multi-function meter and remote monitoring system is verified in the laboratory.The experimental results show that the system can measure the electric energy parameters normally,realize the functions of remote meter reading,fault alarm,parameter display and harmonic analysis.The system runs stably and achieves the expected goal.