Research And Implementation Of The ADE7758-Based Power System Monitoring-Meter

The power quality and harmonic problem are introduced in this paper. Algorithm of power system parameters to be measured in this meter is studied. Methords of power measurement in 3-phase 3-wire and 3-phase 4-wire system is compared. According to the meter needs, a program based on ADE7758 in the 3-pahse 3-wire power measurement is proposed. Two methods to calculate the zero sequence current are deduced based on the symmetrical component method. To resolve the spectrum leakage and fence effect problem of DFT algorithm, the self-convolution window is studied. The hanning self-convolution window DFT algorithm is applied to the power system harmonic analysis.The system design of a ADE7758-Based Power System Monitoring Meter is also described in this paper.Based on modular design, the meter is divided into 4 modules:sensors module,main-board module,LCD and key-board module,mini-board. Use ADE7758 as the energy metering chip, TMSF2812 as the main computing chip and ATmega128 as the mian controlling chip. Realize multi-rate billing,2-31 harmonic analysis, parameter alarm, switch input and output, LCD display, human-computer interaction and RS485 communication.The experiment results show that this meter can meet the requirements of power system monitoring and management.