Design Of Multi-user Energy Meter Based On DSP And GPRS Concentrated Meter-reading Technology

Traditional electrical energy measurement and management based on one-house one meter have been popularized among the entire field of electrical energy measurement.With the development of digital signal processing technology and wireless network technology,it can be realized fully in theory and technology that the electrical energy of many users are measured at different time by a electrical meter and managed centrally.So, Multi-user electrical energy meter based on DSP and GPRS concentrated meter reading technology is designed to provide for convenience of intensive management,and substantially reducing the cost of management.Multi-user electrical energy meter based on DSP and GPRS concentrated meter reading technology consists of DSP electric power measurement unit,MCU data management unit and GPRS wireless communication unit.Measurement unit is used to collect and measure multi-user electric power data,data management is used to manage multi-user electric power data and operate respond to the instruction that power operation center distributes at the same time,wireless communication unit is used to transmit data between energy meter and data management center.In this paper,status and developing of electric energy measurement are introduced firstly,and the most suitable measurement algorithm for many users is selected from several measurement algorithm of active power and reactive power that are compared before.Then,hardware design and software design of the system are expounded in detail.Hardware design includes power source,reset,power off detecting,signal acquisition, interface between DSP and ADC,interface between DSP and MCU, interface between MCU and GPRS unit,and software design includes ADC interrupt program of DSP,DSP measurement program,HPI interface program of DSP,GPRS interface program of MCU.Meanwhile,reliability and optimized analysis carried on the system in the design process are introduced.Finally,active power and reactive power measurement algorithm that are selected before are simulated in Matlab,and parts of key circuits are tested.The results of simulation and test show that traditional electrical energy parameters,such as active power,reactive power,apparent power,power factor,could be measured accurately by the system.Active power measurement accuracy reaches to the level 0.5S,reactive power measurement accuracy reaches to the level 1.